TWI803944B - Bicycle rear sprocket assembly - Google Patents

Bicycle rear sprocket assembly Download PDF

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Publication number
TWI803944B
TWI803944B TW110130827A TW110130827A TWI803944B TW I803944 B TWI803944 B TW I803944B TW 110130827 A TW110130827 A TW 110130827A TW 110130827 A TW110130827 A TW 110130827A TW I803944 B TWI803944 B TW I803944B
Authority
TW
Taiwan
Prior art keywords
sprocket
bicycle rear
internal
sprocket assembly
rear sprocket
Prior art date
Application number
TW110130827A
Other languages
Chinese (zh)
Other versions
TW202212197A (en
Inventor
江村篤裕
藤田寬司
吉田文昭
Original Assignee
日商島野股份有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US15/608,924 external-priority patent/US11332213B2/en
Priority claimed from US15/608,915 external-priority patent/US11059541B2/en
Priority claimed from US15/673,346 external-priority patent/US10377174B2/en
Priority claimed from US15/686,179 external-priority patent/US11220309B2/en
Priority claimed from US15/686,177 external-priority patent/US11179967B2/en
Priority claimed from US15/851,781 external-priority patent/US10946931B2/en
Priority claimed from US15/851,785 external-priority patent/US10752320B2/en
Priority claimed from US15/879,353 external-priority patent/US10625820B2/en
Priority claimed from US15/964,078 external-priority patent/US10889353B2/en
Application filed by 日商島野股份有限公司 filed Critical 日商島野股份有限公司
Publication of TW202212197A publication Critical patent/TW202212197A/en
Publication of TWI803944B publication Critical patent/TWI803944B/en
Application granted granted Critical

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62M—RIDER PROPULSION OF WHEELED VEHICLES OR SLEDGES; POWERED PROPULSION OF SLEDGES OR SINGLE-TRACK CYCLES; TRANSMISSIONS SPECIALLY ADAPTED FOR SUCH VEHICLES
    • B62M9/00—Transmissions characterised by use of an endless chain, belt, or the like
    • B62M9/04—Transmissions characterised by use of an endless chain, belt, or the like of changeable ratio
    • B62M9/06—Transmissions characterised by use of an endless chain, belt, or the like of changeable ratio using a single chain, belt, or the like
    • B62M9/10—Transmissions characterised by use of an endless chain, belt, or the like of changeable ratio using a single chain, belt, or the like involving different-sized wheels, e.g. rear sprocket chain wheels selectively engaged by the chain, belt, or the like
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
    • B62M—RIDER PROPULSION OF WHEELED VEHICLES OR SLEDGES; POWERED PROPULSION OF SLEDGES OR SINGLE-TRACK CYCLES; TRANSMISSIONS SPECIALLY ADAPTED FOR SUCH VEHICLES
    • B62M9/00—Transmissions characterised by use of an endless chain, belt, or the like
    • B62M9/04—Transmissions characterised by use of an endless chain, belt, or the like of changeable ratio
    • B62M9/06—Transmissions characterised by use of an endless chain, belt, or the like of changeable ratio using a single chain, belt, or the like
    • B62M9/10—Transmissions characterised by use of an endless chain, belt, or the like of changeable ratio using a single chain, belt, or the like involving different-sized wheels, e.g. rear sprocket chain wheels selectively engaged by the chain, belt, or the like
    • B62M9/12—Transmissions characterised by use of an endless chain, belt, or the like of changeable ratio using a single chain, belt, or the like involving different-sized wheels, e.g. rear sprocket chain wheels selectively engaged by the chain, belt, or the like the chain, belt, or the like being laterally shiftable, e.g. using a rear derailleur
    • B62M9/121—Rear derailleurs

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Gears, Cams (AREA)
  • Automatic Cycles, And Cycles In General (AREA)

Abstract

A bicycle rear sprocket assembly comprises a plurality of sprockets and a sprocket carrier configured to support at least one of the plurality of sprockets. The sprocket carrier includes at least ten internal spline teeth and a circumferentially extending non-splined portion. The at least ten internal spline teeth are configured to engage with the sprocket support body of the bicycle rear hub assembly. The at least ten internal spline teeth extend in an axial direction with respect to a rotational center axis of the bicycle rear sprocket assembly and are spaced apart from each other in a circumferential direction with respect to the rotational center axis. The circumferentially extending non-splined portion is disposed to be adjacent to the at least ten internal spline teeth in the axial direction and recessed from the at least ten internal spline teeth in a radial direction with respect to the rotational center axis.

Description

自行車後鏈輪總成Bicycle rear sprocket assembly

本發明係關於一種自行車後鏈輪總成。The invention relates to a bicycle rear sprocket assembly.

騎車正變成更日益流行的消遣形式以及交通方式。此外，騎車已變成業餘及專業人員兩者之非常流行的競技運動。不論自行車是用於消遣、交通抑或是用於競賽，自行車行業正不斷地改良自行車之各種組件。已經充分重新設計之一個自行車組件為鏈輪。Cycling is becoming an increasingly popular form of recreation as well as a mode of transportation. Furthermore, cycling has become a very popular competitive sport for both amateurs and professionals. Whether the bicycle is used for recreation, transportation, or competition, the bicycle industry is constantly improving the various components of the bicycle. One of the bicycle components that has been substantially redesigned is the sprocket.

根據本發明之第一態樣，一種自行車後鏈輪總成經構形以安裝至一自行車後輪轂總成之一鏈輪支撐主體。該自行車後鏈輪總成包含複數個鏈輪及經構形以支撐該複數個鏈輪中之至少一者的一鏈輪托架。該鏈輪托架包括至少十個內部花鍵齒及一沿圓周延伸非花鍵部分。該至少十個內部花鍵齒經構形以與該自行車後輪轂總成之該鏈輪支撐主體嚙合。該至少十個內部花鍵齒在一軸向方向上相對於該自行車後鏈輪總成之一旋轉中心軸線延伸，且在一圓周方向上相對於該旋轉中心軸線彼此間隔開。該沿圓周延伸非花鍵部分經安置以在該軸向方向上鄰近於該至少十個內部花鍵齒，且在一徑向方向上相對於該旋轉中心軸線自該至少十個內部花鍵齒凹入。 在根據第一態樣之自行車後鏈輪總成之情況下，有可能減輕自行車後鏈輪總成之重量，同時維持或改良自行車後鏈輪總成之耐久性。 根據本發明之第二態樣，如第一態樣之自行車後鏈輪總成經構形以使得該至少十個內部花鍵齒之一總數目等於或大於20。 在根據第二態樣之自行車後鏈輪總成之情況下，有可能改良內部花鍵齒之製造效率，同時維持或改良自行車後鏈輪總成之耐久性。 根據本發明之第三態樣，如第二態樣之自行車後鏈輪總成經構形以使得該至少十個內部花鍵齒之一總數目等於或小於25。 在根據第三態樣之自行車後鏈輪總成之情況下，有可能改良內部花鍵齒之製造效率，同時維持或改良自行車後鏈輪總成之耐久性。 根據本發明之第四態樣，如第一態樣之自行車後鏈輪總成經構形以使得該至少十個內部花鍵齒之一總數目在22至24之範圍內。 在根據第四態樣之自行車後鏈輪總成之情況下，有可能改良內部花鍵齒之製造效率，同時維持或改良自行車後鏈輪總成之耐久性。 根據本發明之第五態樣，如第一態樣至第四態樣中任一項之自行車後鏈輪總成經構形以使得該至少十個內部花鍵齒中之至少兩個內部花鍵齒相對於該自行車後鏈輪總成之一旋轉中心軸線以一第一內部周節角沿圓周配置。該第一內部周節角在13度至17度之範圍內。 在根據第五態樣之自行車後鏈輪總成之情況下，有可能改良內部花鍵齒之製造效率，同時維持或改良自行車後鏈輪總成之耐久性。 根據本發明之第六態樣，如第五態樣之自行車後鏈輪總成經構形以使得該第一內部周節角為15度。 在根據第六態樣之自行車後鏈輪總成之情況下，有可能改良內部花鍵齒之製造效率，同時維持或改良自行車後鏈輪總成之耐久性。 根據本發明之第七態樣，如第五態樣之自行車後鏈輪總成經構形以使得該至少十個內部花鍵齒中之至少其他兩個內部花鍵齒相對於該旋轉中心軸線以一第二內部周節角沿圓周配置。該第二內部周節角不同於該第一內部周節角。 在根據第七態樣之自行車後鏈輪總成之情況下，有可能易於在正確圓周位置中將自行車後鏈輪總成附接至自行車輪轂總成。 根據本發明之第八態樣，如第七態樣之自行車後鏈輪總成經構形以使得該第二內部周節角在28度至32度之範圍內。 在根據第八態樣之自行車後鏈輪總成之情況下，有可能易於在正確圓周位置中將自行車後鏈輪總成附接至自行車輪轂總成。 根據本發明之第九態樣，如第七態樣之自行車後鏈輪總成經構形以使得該第二內部周節角為30度。 在根據第九態樣之自行車後鏈輪總成之情況下，有可能易於在正確圓周位置中將自行車後鏈輪總成附接至自行車輪轂總成。 根據本發明之第十態樣，如第七態樣至第九態樣中任一項之自行車後鏈輪總成經構形以使得該第一內部周節角為該第二內部周節角之一半。 在根據第十態樣之自行車後鏈輪總成之情況下，有可能易於在正確圓周位置中將自行車後鏈輪總成附接至自行車輪轂總成。 根據本發明之第十一態樣，如第一態樣至第十態樣中任一項之自行車後鏈輪總成經構形以使得該至少十個內部花鍵齒包括複數個內部花鍵傳動表面以在踩踏期間接收來自該自行車後輪轂總成之一傳動旋轉力。該複數個內部花鍵傳動表面各自包括一徑向最外邊緣、一徑向最內邊緣及自該徑向最外邊緣至該徑向最內邊緣界定之一徑向長度。該等徑向長度之總和在11 mm至14 mm之範圍內。 在根據第十一態樣之自行車後鏈輪總成之情況下，有可能增大複數個內部花鍵傳動表面之徑向長度。此改良第二鏈輪之強度，同時改良內部花鍵齒之製造效率。 根據本發明之第十二態樣，如第十一態樣之自行車後鏈輪總成經構形以使得該等徑向長度之該總和在12 mm至13 mm之範圍內。 在根據第十二態樣之自行車後鏈輪總成之情況下，有可能增大複數個內部花鍵傳動表面之徑向長度。此改良第二鏈輪之強度，同時改良內部花鍵齒之製造效率。 根據本發明之第十三態樣，如第一態樣至第十二態樣中任一項之自行車後鏈輪總成經構形以使得該沿圓周延伸非花鍵部分經安置以使得該至少十個內部花鍵齒由該沿圓周延伸非花鍵部分在該軸向方向上劃分成至少十個第一內部花鍵齒及至少十個第二內部花鍵齒。 在根據第十三態樣之自行車後鏈輪總成之情況下，有可能減輕自行車後鏈輪總成之重量，同時使扭矩傳遞之平衡最佳化。 根據本發明之第十四態樣，如第十三態樣之自行車後鏈輪總成經構形以使得該複數個第一內部花鍵齒具有在4 mm至5 mm之範圍內的一第一軸向長度。 在根據第十四態樣之自行車後鏈輪總成之情況下，有可能減輕自行車後鏈輪總成之重量，同時使扭矩傳遞之平衡最佳化。 根據本發明之第十五態樣，如第十四態樣之自行車後鏈輪總成經構形以使得該複數個第二內部花鍵齒具有在4.5 mm至5.5 mm之範圍內的一第二軸向長度。 在根據第十五態樣之自行車後鏈輪總成之情況下，有可能減輕自行車後鏈輪總成之重量，同時使扭矩傳遞之平衡最佳化。 根據本發明之第十六態樣，如第一態樣至第十五態樣中任一項之自行車後鏈輪總成經構形以使得該沿圓周延伸非花鍵部分具有在該軸向方向上界定之一軸向非花鍵長度。該軸向非花鍵長度在7 mm至9 mm之範圍內。 在根據第十六態樣之自行車後鏈輪總成之情況下，有可能減輕自行車後鏈輪總成之重量，同時使扭矩傳遞之平衡最佳化。 根據本發明之第十七態樣，如第一態樣至第十六態樣中任一項之自行車後鏈輪總成經構形以使得該至少十個內部花鍵齒之一軸向長度及該沿圓周延伸非花鍵部分之一軸向非花鍵長度的一總和在16 mm至21 mm之範圍內。 在根據第十七態樣之自行車後鏈輪總成之情況下，有可能減輕自行車後鏈輪總成之重量，同時使扭矩傳遞之平衡最佳化。 根據本發明之第十八態樣，如第一態樣至第十七態樣中任一項之自行車後鏈輪總成經構形以使得該沿圓周延伸非花鍵部分在該圓周方向上完全延伸。 在根據第十八態樣之自行車後鏈輪總成之情況下，有可能減輕自行車後鏈輪總成之重量。 根據本發明之第十九態樣，如第一態樣至第十八態樣中任一項之自行車後鏈輪總成經構形以使得該鏈輪托架由一金屬材料製成。 在根據第十九態樣之自行車後鏈輪總成之情況下，有可能減輕自行車後鏈輪總成之重量。 根據本發明之第二十態樣，如第十九態樣之自行車後鏈輪總成經構形以使得該金屬材料包括鋁。 在根據第二十態樣之自行車後鏈輪總成之情況下，有可能減輕自行車後鏈輪總成之重量。 根據本發明之第二十一態樣，一種自行車後鏈輪總成包含一第一鏈輪構件、一第二鏈輪構件及一鏈輪托架。該第一鏈輪構件具有一第一最大鏈輪直徑，且包括一第一鏈輪主體及相對於該自行車後鏈輪總成之一旋轉中心軸線自該第一鏈輪主體徑向向外延伸之複數個第一鏈輪齒。該第二鏈輪構件具有大於該第一最大鏈輪直徑之一第二最大鏈輪直徑。該第二鏈輪構件包括一第二鏈輪主體及相對於該旋轉中心軸線自該第二鏈輪主體徑向向外延伸之複數個第二鏈輪齒。該鏈輪托架包括複數個鏈輪安裝部分。該複數個鏈輪安裝部分中之至少兩者各自具有相對於該旋轉中心軸線之一徑向延伸表面及一軸向延伸表面。該複數個鏈輪安裝部分中之該至少兩者在一徑向方向上相對於該旋轉中心軸線彼此鄰近。該第一鏈輪構件固定至該第二鏈輪構件。該第二鏈輪構件固定至該複數個鏈輪安裝部分之一一級鏈輪安裝部分之一一級徑向延伸表面。該第二鏈輪構件在一軸向方向上相對於該旋轉中心軸線安置於該第一鏈輪構件與該一級鏈輪安裝部分之該一級徑向延伸表面之間。 在根據第二十一態樣之自行車後鏈輪總成之情況下，有可能減輕自行車後鏈輪總成之重量。 根據本發明之第二十二態樣，如第二十一態樣之自行車後鏈輪總成經構形以使得該第二鏈輪構件藉由一第一鏈輪緊固件固定至該一級鏈輪安裝部分之該一級徑向延伸表面。該第一鏈輪構件藉由該第一鏈輪緊固件固定至該第二鏈輪構件。 在根據第二十二態樣之自行車後鏈輪總成之情況下，有可能進一步減輕自行車後鏈輪總成之重量。 根據本發明之第二十三態樣，如第二十一態樣或第二十二態樣之自行車後鏈輪總成進一步包含一第三鏈輪構件，該第三鏈輪構件具有大於該第二最大鏈輪直徑之一第三最大鏈輪直徑。該第三鏈輪構件包括一第三鏈輪主體及相對於該旋轉中心軸線自該第三鏈輪主體徑向向外延伸之複數個第三鏈輪齒。該第三鏈輪構件固定至該複數個鏈輪安裝部分之一二級鏈輪安裝部分之一二級徑向延伸表面。 在根據第二十三態樣之自行車後鏈輪總成之情況下，有可能進一步減輕自行車後鏈輪總成之重量。 根據本發明之第二十四態樣，如第二十三態樣之自行車後鏈輪總成經構形以使得該第二鏈輪構件藉由一第一鏈輪緊固件固定至該一級鏈輪安裝部分之該一級徑向延伸表面。該第一鏈輪構件藉由該第一鏈輪緊固件固定至該第二鏈輪構件。該第三鏈輪構件藉由不同於該第一鏈輪緊固件之一第二鏈輪緊固件固定至該二級鏈輪安裝部分之該二級徑向延伸表面。 在根據第二十四態樣之自行車後鏈輪總成之情況下，有可能進一步減輕自行車後鏈輪總成之重量。 根據本發明之第二十五態樣，如第二十一態樣至第二十四態樣中任一項之自行車後鏈輪總成進一步包含一第四鏈輪構件及一第五鏈輪構件。該第四鏈輪構件具有大於該第二最大鏈輪直徑之一第四最大鏈輪直徑。該第四鏈輪構件包括一第四鏈輪主體及相對於該旋轉中心軸線自該第四鏈輪主體徑向向外延伸之複數個第四鏈輪齒。該第五鏈輪構件具有大於該第四最大鏈輪直徑之一第五最大鏈輪直徑。該第五鏈輪構件包括一第五鏈輪主體及相對於該旋轉中心軸線自該第五鏈輪主體徑向向外延伸之複數個第五鏈輪齒。該第四鏈輪構件固定至該第五鏈輪構件。該第五鏈輪構件固定至該複數個鏈輪安裝部分之一三級鏈輪安裝部分之一三級徑向延伸表面。 在根據第二十五態樣之自行車後鏈輪總成之情況下，有可能減輕具有寬齒輪範圍之自行車後鏈輪總成之重量。 根據本發明之第二十六態樣，如第二十五態樣之自行車後鏈輪總成經構形以使得該第五鏈輪構件藉由一第三鏈輪緊固件固定至該三級鏈輪安裝部分之該三級徑向延伸表面。該第四鏈輪構件藉由該第三鏈輪緊固件固定至該第五鏈輪構件。 在根據第二十六態樣之自行車後鏈輪總成之情況下，有可能減輕具有寬齒輪範圍之自行車後鏈輪總成之重量。 根據本發明之第二十七態樣，如第二十五態樣之自行車後鏈輪總成進一步包含一第三鏈輪構件，該第三鏈輪構件具有大於該第二最大鏈輪直徑之一第三最大鏈輪直徑。該第三鏈輪構件包括一第三鏈輪主體及相對於該旋轉中心軸線自該第三鏈輪主體徑向向外延伸之複數個第三鏈輪齒。該第三鏈輪構件固定至該複數個鏈輪安裝部分之一二級鏈輪安裝部分之一二級徑向延伸表面。該第四鏈輪構件之該第四最大鏈輪直徑大於該第三最大鏈輪直徑。 在根據第二十七態樣之自行車後鏈輪總成之情況下，有可能減輕具有寬齒輪範圍之自行車後鏈輪總成之重量。 根據本發明之第二十八態樣，如第二十五態樣或第二十六態樣之自行車後鏈輪總成進一步包含一第六鏈輪構件，該第六鏈輪構件具有大於該第五最大鏈輪直徑之一第六最大鏈輪直徑。該第六鏈輪構件包括一第六鏈輪主體及相對於該旋轉中心軸線自該第六鏈輪主體徑向向外延伸之複數個第六鏈輪齒。該第六鏈輪構件固定至該複數個鏈輪安裝部分之一四級鏈輪安裝部分之一四級徑向延伸表面。 在根據第二十八態樣之自行車後鏈輪總成之情況下，有可能減輕自行車後鏈輪總成之重量。 According to a first aspect of the present invention, a bicycle rear sprocket assembly is configured to be mounted to a sprocket support body of a bicycle rear hub assembly. The bicycle rear sprocket assembly includes a plurality of sprockets and a sprocket carrier configured to support at least one of the plurality of sprockets. The sprocket carrier includes at least ten internal spline teeth and a circumferentially extending non-spline portion. The at least ten internal spline teeth are configured to engage with the sprocket support body of the bicycle rear hub assembly. The at least ten internal spline teeth extend in an axial direction relative to a central axis of rotation of the bicycle rear sprocket assembly and are spaced apart from each other in a circumferential direction relative to the central axis of rotation. The circumferentially extending non-splined portion is disposed adjacent to the at least ten inner spline teeth in the axial direction and from the at least ten inner spline teeth in a radial direction relative to the central axis of rotation recessed. In the case of the bicycle rear sprocket assembly according to the first aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly while maintaining or improving the durability of the bicycle rear sprocket assembly. According to a second aspect of the invention, the bicycle rear sprocket assembly of the first aspect is configured such that the total number of one of the at least ten internal spline teeth is equal to or greater than twenty. In the case of the bicycle rear sprocket assembly according to the second aspect, it is possible to improve the manufacturing efficiency of the internal spline teeth while maintaining or improving the durability of the bicycle rear sprocket assembly. According to a third aspect of the invention, the bicycle rear sprocket assembly of the second aspect is configured such that the total number of one of the at least ten internal spline teeth is equal to or less than twenty-five. In the case of the bicycle rear sprocket assembly according to the third aspect, it is possible to improve the manufacturing efficiency of the internal spline teeth while maintaining or improving the durability of the bicycle rear sprocket assembly. According to a fourth aspect of the invention, the bicycle rear sprocket assembly of the first aspect is configured such that the total number of one of the at least ten internal spline teeth is in the range of 22-24. In the case of the bicycle rear sprocket assembly according to the fourth aspect, it is possible to improve the manufacturing efficiency of the internal spline teeth while maintaining or improving the durability of the bicycle rear sprocket assembly. According to a fifth aspect of the present invention, the bicycle rear sprocket assembly according to any one of the first to fourth aspects is configured such that at least two of the at least ten internal spline teeth The spline teeth are arranged along the circumference at a first inner circumferential pitch angle with respect to a rotation center axis of the bicycle rear sprocket assembly. The first inner circumferential pitch angle is in the range of 13 degrees to 17 degrees. In the case of the bicycle rear sprocket assembly according to the fifth aspect, it is possible to improve the manufacturing efficiency of the internal spline teeth while maintaining or improving the durability of the bicycle rear sprocket assembly. According to a sixth aspect of the present invention, the bicycle rear sprocket assembly of the fifth aspect is configured such that the first inner circumferential pitch angle is 15 degrees. In the case of the bicycle rear sprocket assembly according to the sixth aspect, it is possible to improve the manufacturing efficiency of the internal spline teeth while maintaining or improving the durability of the bicycle rear sprocket assembly. According to a seventh aspect of the present invention, the bicycle rear sprocket assembly according to the fifth aspect is configured so that at least two of the at least ten internal spline teeth are relative to the rotation center axis It is arranged along the circumference with a second inner circumferential pitch angle. The second inner circumferential pitch angle is different from the first inner circumferential pitch angle. In the case of the bicycle rear sprocket assembly according to the seventh aspect, it is possible to easily attach the bicycle rear sprocket assembly to the bicycle hub assembly in the correct circumferential position. According to an eighth aspect of the present invention, the bicycle rear sprocket assembly of the seventh aspect is configured such that the second inner circumferential pitch angle is in the range of 28 degrees to 32 degrees. In the case of the bicycle rear sprocket assembly according to the eighth aspect, it is possible to easily attach the bicycle rear sprocket assembly to the bicycle hub assembly in the correct circumferential position. According to a ninth aspect of the present invention, the bicycle rear sprocket assembly of the seventh aspect is configured such that the second inner circumferential pitch angle is 30 degrees. In the case of the bicycle rear sprocket assembly according to the ninth aspect, it is possible to easily attach the bicycle rear sprocket assembly to the bicycle hub assembly in the correct circumferential position. According to a tenth aspect of the present invention, the bicycle rear sprocket assembly according to any one of the seventh to ninth aspects is configured such that the first internal pitch angle is the second internal pitch angle one half. In the case of the bicycle rear sprocket assembly according to the tenth aspect, it is possible to easily attach the bicycle rear sprocket assembly to the bicycle hub assembly in the correct circumferential position. According to an eleventh aspect of the present invention, the bicycle rear sprocket assembly of any one of the first to tenth aspects is configured such that the at least ten internal spline teeth include a plurality of internal splines and a transmission surface to receive a transmission rotational force from one of the rear hub assemblies of the bicycle during pedaling. Each of the plurality of internal splined drive surfaces includes a radially outermost edge, a radially innermost edge, and a radial length defined from the radially outermost edge to the radially innermost edge. The sum of these radial lengths is in the range of 11 mm to 14 mm. In the case of the bicycle rear sprocket assembly according to the eleventh aspect, it is possible to increase the radial length of the plurality of internal spline drive surfaces. This improves the strength of the second sprocket while improving the manufacturing efficiency of the internal spline teeth. According to a twelfth aspect of the present invention, the bicycle rear sprocket assembly as in the eleventh aspect is configured such that the sum of the radial lengths is in the range of 12 mm to 13 mm. In the case of the bicycle rear sprocket assembly according to the twelfth aspect, it is possible to increase the radial length of the plurality of internal spline drive surfaces. This improves the strength of the second sprocket while improving the manufacturing efficiency of the internal spline teeth. According to a thirteenth aspect of the present invention, the bicycle rear sprocket assembly of any one of the first to twelfth aspects is configured such that the circumferentially extending non-spline portion is arranged so that the At least ten internal spline teeth are divided by the circumferentially extending non-spline portion in the axial direction into at least ten first internal spline teeth and at least ten second internal spline teeth. In the case of the bicycle rear sprocket assembly according to the thirteenth aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly while optimizing the balance of torque transmission. According to a fourteenth aspect of the present invention, the bicycle rear sprocket assembly of the thirteenth aspect is configured such that the plurality of first internal spline teeth have a first spline in the range of 4 mm to 5 mm. an axial length. In the case of the bicycle rear sprocket assembly according to the fourteenth aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly while optimizing the balance of torque transmission. According to a fifteenth aspect of the present invention, the bicycle rear sprocket assembly of the fourteenth aspect is configured such that the plurality of second internal spline teeth have a first spline in the range of 4.5 mm to 5.5 mm. Two axial lengths. In the case of the bicycle rear sprocket assembly according to the fifteenth aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly while optimizing the balance of torque transmission. According to a sixteenth aspect of the present invention, the bicycle rear sprocket assembly of any one of the first to fifteenth aspects is configured such that the circumferentially extending non-spline portion has a The direction defines an axial non-spline length. The axial non-spline length is in the range of 7 mm to 9 mm. In the case of the bicycle rear sprocket assembly according to the sixteenth aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly while optimizing the balance of torque transmission. According to a seventeenth aspect of the present invention, the bicycle rear sprocket assembly according to any one of the first to sixteenth aspects is configured such that an axial length of the at least ten internal spline teeth and a sum of axial non-spline lengths of the circumferentially extending non-spline portion is in the range of 16 mm to 21 mm. In the case of the bicycle rear sprocket assembly according to the seventeenth aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly while optimizing the balance of torque transmission. According to an eighteenth aspect of the present invention, the bicycle rear sprocket assembly according to any one of the first aspect to the seventeenth aspect is configured such that the circumferentially extending non-spline portion is in the circumferential direction fully extended. In the case of the bicycle rear sprocket assembly according to the eighteenth aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly. According to a nineteenth aspect of the present invention, the bicycle rear sprocket assembly of any one of the first to eighteenth aspects is configured such that the sprocket bracket is made of a metal material. In the case of the bicycle rear sprocket assembly according to the nineteenth aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly. According to a twentieth aspect of the present invention, the bicycle rear sprocket assembly of the nineteenth aspect is configured such that the metallic material includes aluminum. In the case of the bicycle rear sprocket assembly according to the twentieth aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly. According to a twenty-first aspect of the present invention, a bicycle rear sprocket assembly includes a first sprocket member, a second sprocket member, and a sprocket bracket. The first sprocket member has a first maximum sprocket diameter and includes a first sprocket body and extends radially outward from the first sprocket body relative to a central axis of rotation of the bicycle rear sprocket assembly a plurality of first sprocket teeth. The second sprocket member has a second largest sprocket diameter that is greater than one of the first largest sprocket diameter. The second sprocket member includes a second sprocket main body and a plurality of second sprocket teeth extending radially outward from the second sprocket main body relative to the rotation center axis. The sprocket bracket includes a plurality of sprocket mounting portions. At least two of the plurality of sprocket mounting portions each have a radially extending surface and an axially extending surface relative to the rotation center axis. The at least two of the plurality of sprocket mounting portions are adjacent to each other in a radial direction relative to the rotation center axis. The first sprocket member is fixed to the second sprocket member. The second sprocket member is fixed to a primary radially extending surface of one of the plurality of sprocket mounting portions. The second sprocket member is disposed between the first sprocket member and the primary radially extending surface of the primary sprocket mounting portion in an axial direction with respect to the rotation center axis. In the case of the bicycle rear sprocket assembly according to the twenty-first aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly. According to a twenty-second aspect of the present invention, the bicycle rear sprocket assembly of the twenty-first aspect is configured such that the second sprocket member is fixed to the primary chain by a first sprocket fastener The primary radially extending surface of the wheel mounting portion. The first sprocket member is secured to the second sprocket member by the first sprocket fastener. In the case of the bicycle rear sprocket assembly according to the twenty-second aspect, it is possible to further reduce the weight of the bicycle rear sprocket assembly. According to the twenty-third aspect of the present invention, the bicycle rear sprocket assembly of the twenty-first aspect or the twenty-second aspect further includes a third sprocket member, and the third sprocket member has a The second largest sprocket diameter is one of the third largest sprocket diameters. The third sprocket member includes a third sprocket main body and a plurality of third sprocket teeth extending radially outward from the third sprocket main body relative to the rotation center axis. The third sprocket member is fixed to a secondary radially extending surface of one of the secondary sprocket mounting portions of the plurality of sprocket mounting portions. In the case of the bicycle rear sprocket assembly according to the twenty-third aspect, it is possible to further reduce the weight of the bicycle rear sprocket assembly. According to a twenty-fourth aspect of the present invention, the bicycle rear sprocket assembly of the twenty-third aspect is configured such that the second sprocket member is fixed to the primary chain by a first sprocket fastener The primary radially extending surface of the wheel mounting portion. The first sprocket member is secured to the second sprocket member by the first sprocket fastener. The third sprocket member is secured to the secondary radially extending surface of the secondary sprocket mounting portion by a second sprocket fastener different from the first sprocket fastener. In the case of the bicycle rear sprocket assembly according to the twenty-fourth aspect, it is possible to further reduce the weight of the bicycle rear sprocket assembly. According to the twenty-fifth aspect of the present invention, the bicycle rear sprocket assembly according to any one of the twenty-first aspect to the twenty-fourth aspect further includes a fourth sprocket member and a fifth sprocket member. The fourth sprocket member has a fourth largest sprocket diameter that is greater than one of the second largest sprocket diameters. The fourth sprocket member includes a fourth sprocket main body and a plurality of fourth sprocket teeth extending radially outward from the fourth sprocket main body relative to the rotation center axis. The fifth sprocket member has a fifth largest sprocket diameter that is greater than one of the fourth largest sprocket diameters. The fifth sprocket member includes a fifth sprocket main body and a plurality of fifth sprocket teeth extending radially outward from the fifth sprocket main body relative to the rotation center axis. The fourth sprocket member is fixed to the fifth sprocket member. The fifth sprocket member is fixed to a tertiary radially extending surface of one of the tertiary sprocket mounting portions of the plurality of sprocket mounting portions. In the case of the bicycle rear sprocket assembly according to the twenty-fifth aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly having a wide gear range. According to a twenty-sixth aspect of the present invention, the bicycle rear sprocket assembly of the twenty-fifth aspect is configured such that the fifth sprocket member is fixed to the third stage by a third sprocket fastener. The three-stage radially extending surface of the sprocket mounting portion. The fourth sprocket member is secured to the fifth sprocket member by the third sprocket fastener. In the case of the bicycle rear sprocket assembly according to the twenty-sixth aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly having a wide gear range. According to the twenty-seventh aspect of the present invention, the bicycle rear sprocket assembly of the twenty-fifth aspect further includes a third sprocket member having a diameter larger than the second largest sprocket diameter. - a third largest sprocket diameter. The third sprocket member includes a third sprocket main body and a plurality of third sprocket teeth extending radially outward from the third sprocket main body relative to the rotation center axis. The third sprocket member is fixed to a secondary radially extending surface of one of the secondary sprocket mounting portions of the plurality of sprocket mounting portions. The fourth largest sprocket diameter of the fourth sprocket member is larger than the third largest sprocket diameter. In the case of the bicycle rear sprocket assembly according to the twenty-seventh aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly having a wide gear range. According to the twenty-eighth aspect of the present invention, the bicycle rear sprocket assembly of the twenty-fifth aspect or the twenty-sixth aspect further includes a sixth sprocket member, and the sixth sprocket member has a One of the fifth largest sprocket diameters and the sixth largest sprocket diameter. The sixth sprocket member includes a sixth sprocket main body and a plurality of sixth sprocket teeth extending radially outward from the sixth sprocket main body relative to the rotation center axis. The sixth sprocket member is fixed to a four-stage radially extending surface of one of the four-stage sprocket mounting portions of the plurality of sprocket mounting portions. In the case of the bicycle rear sprocket assembly according to the twenty-eighth aspect, it is possible to reduce the weight of the bicycle rear sprocket assembly.

本申請案為2018年1月24日申請之美國專利申請案第15/879,353號之部分接續申請案。本申請案之內容以全文引用之方式併入本文中。 現將參看附圖描述實施例，其中相似參考數字指定在各種圖式中之對應或相同元件。 第一實施例 首先參考圖1，根據第一實施例之自行車後鏈輪總成10包含複數個鏈輪SP。複數個鏈輪SP包括第一鏈輪SP1及第二鏈輪SP2。複數個鏈輪SP進一步包括第三鏈輪SP3及第四鏈輪SP4。複數個鏈輪SP進一步包括第五鏈輪SP5至第十二鏈輪SP12。在此實施例中，第一鏈輪SP1至第十二鏈輪SP12亦可分別被稱作鏈輪SP1至SP12。除鏈輪SP1及鏈輪SP2以外，第三鏈輪SP3可為選自複數個鏈輪SP3至SP12之任何鏈輪。除鏈輪SP1、鏈輪SP2及選為鏈輪SP3之鏈輪以外，第四鏈輪SP4可為選自複數個鏈輪SP3至SP12之任何鏈輪。 第一鏈輪SP1亦可被稱作第一鏈輪車輪SP1。第二鏈輪SP2亦可被稱作第三鏈輪車輪SP2。第三鏈輪SP3亦可被稱作第四鏈輪車輪SP3。第四鏈輪SP4亦可被稱作第二鏈輪車輪SP4。亦即，自行車後鏈輪總成10包含第一鏈輪車輪SP1、第二鏈輪車輪SP4及第三鏈輪車輪SP2。自行車後鏈輪總成10進一步包含第四鏈輪車輪SP3。第一鏈輪車輪SP1亦可被稱作鏈輪SP1。第二鏈輪車輪SP4亦可被稱作鏈輪SP4。第三鏈輪車輪SP2亦可被稱作鏈輪SP2。第四鏈輪車輪SP3亦可被稱作鏈輪SP3。鏈輪SP1至SP12之總數目不限於此實施例。 如圖1中所見，自行車後鏈輪總成10具有旋轉中心軸線A1。自行車後鏈輪總成10由自行車後輪轂總成H圍繞旋轉中心軸線A1相對於自行車框架(未展示)可旋轉地支撐。自行車後鏈輪總成10經構形以安裝至自行車後輪轂總成H之鏈輪支撐主體H2 (圖2)。在此實施例中，自行車後鏈輪總成10藉由鎖定構件H1緊固至自行車後輪轂總成H之鏈輪支撐主體H2。自行車後鏈輪總成10經構形以與自行車鏈C嚙合以在踩踏期間在自行車鏈C與自行車後鏈輪總成10之間傳遞傳動旋轉力F1。在踩踏期間，自行車後鏈輪總成10在傳動旋轉方向D11上圍繞旋轉中心軸線A1旋轉。傳動旋轉方向D11係沿圓周方向D1相對於自行車後鏈輪總成10之旋轉中心軸線A1界定。反向旋轉方向D12為傳動旋轉方向D11之相反方向，且係沿圓周方向D1界定。 在此實施例中，鏈輪SP3為自行車後鏈輪總成10中之最大鏈輪。第十二鏈輪SP12為自行車後鏈輪總成10中之最小鏈輪。第一鏈輪SP1具有最大齒底直徑TD1。最大齒底直徑TD1亦可被稱作第一最大齒底直徑TD1。亦即，第一鏈輪車輪SP1具有第一最大齒底直徑TD1。第二鏈輪SP2具有大於第一鏈輪SP1之最大齒底直徑TD1的額外最大齒底直徑TD2。額外最大齒底直徑TD2亦可被稱作第三最大齒底直徑TD2。亦即，第三鏈輪車輪SP2具有大於第一鏈輪車輪SP1之第一最大齒底直徑TD1的第三最大齒底直徑TD2。第二鏈輪車輪SP4具有小於第一鏈輪車輪SP1之第一最大齒底直徑TD1的第二最大齒底直徑TD4。第三鏈輪SP3具有大於第一鏈輪SP1之最大齒底直徑TD1的額外最大齒底直徑TD3。鏈輪SP5至SP12分別具有第五最大齒底直徑TD5至第十二最大齒底直徑TD12。 鏈輪SP1至SP12之間的尺寸關係不限於此實施例。舉例而言，額外最大齒底直徑TD2可等於或小於第一鏈輪SP1之最大齒底直徑TD1。第二最大齒底直徑TD4可等於或大於第一鏈輪車輪SP1之第一最大齒底直徑TD1。 如圖2中所見，第一鏈輪車輪SP1在軸向方向D2上相對於旋轉中心軸線A1安置於第二鏈輪車輪SP4與第三鏈輪車輪SP2之間。第三鏈輪車輪SP2在軸向方向D2上安置於第一鏈輪車輪SP1與第四鏈輪車輪SP3之間。第二鏈輪SP2在軸向方向D2上相對於自行車後鏈輪總成10之旋轉中心軸線A1鄰近於第一鏈輪SP1，而在第一鏈輪SP1與第二鏈輪SP2之間無另一鏈輪。第三鏈輪SP3在軸向方向D2上相對於自行車後鏈輪總成10之旋轉中心軸線A1鄰近於第二鏈輪SP2。而在第二鏈輪SP2與第三鏈輪SP3之間無另一鏈輪。第四鏈輪SP4在軸向方向D2上相對於自行車後鏈輪總成10之旋轉中心軸線A1鄰近於第一鏈輪SP1，而在第一鏈輪SP1與第四鏈輪SP4之間無另一鏈輪。第三鏈輪SP3、第二鏈輪SP2、第一鏈輪SP1及第四鏈輪SP4至第十二鏈輪SP12以此次序在軸向方向D2上配置。 在此實施例中，鏈輪SP1至SP12為彼此分離之構件。然而，鏈輪SP1至SP12中之至少兩者可至少部分地彼此一體地設置。具體言之，鏈輪SP1至SP12中之至少兩者可一體地設置為整體單件式構件。替代地，鏈輪SP1至SP12中之至少兩者可藉由諸如鉚釘之至少一個機械緊固件或藉由黏附劑、擴散結合等等連接至彼此。鏈輪SP1至SP12由金屬材料製成。在此實施例中，第一鏈輪SP1由鈦製成。第二鏈輪SP2由鋁製成。第三鏈輪SP3由鋁製成。第四鏈輪SP4由鈦製成。然而，第一鏈輪SP1至第十二鏈輪SP12之材料不限於此實施例。鏈輪SP1至SP12中之至少一者可由另一金屬材料或非金屬材料製成。 如圖3中所見，第一鏈輪SP1包括鏈輪主體SP1A及複數個鏈輪齒SP1B。複數個鏈輪齒SP1B相對於自行車後鏈輪總成10之旋轉中心軸線A1自鏈輪主體SP1A徑向向外延伸。第一鏈輪SP1之總齒數(至少一個鏈輪齒SP1B之總數目)為39。然而，第一鏈輪SP1之複數個鏈輪齒SP1B之總數目不限於此實施例。 第一鏈輪SP1包括複數個齒底SP1C。齒底SP1C設置於鏈輪齒SP1B中之鄰近兩者之間。複數個齒底SP1C界定具有最大齒底直徑TD1之齒根圓RC1。如本文中所使用，術語「最大齒底直徑」欲為在所有齒底之形狀彼此相同之情況下由齒底界定的齒根圓之直徑，或欲為在具有若干形狀之齒底設置於一個鏈輪中以使得複數個齒根圓界定於鏈輪中之情況下由至少一個齒底界定的最大齒根圓之直徑。術語定義可應用於第一鏈輪SP1至第十二鏈輪SP12中之任何鏈輪。 第一鏈輪SP1亦可被稱作第六鏈輪構件SP1。鏈輪主體SP1A亦可被稱作第六鏈輪主體SP1A。鏈輪齒SP1B亦可被稱作第六鏈輪齒SP1B。因此，自行車後鏈輪總成10進一步包含第六鏈輪構件SP1。第六鏈輪構件SP1包括第六鏈輪主體SP1A及相對於旋轉中心軸線A1自第六鏈輪主體SP1A徑向向外延伸之複數個第六鏈輪齒SP1B。第六鏈輪構件SP1具有第六最大鏈輪直徑MD1。第六鏈輪齒SP1B中之至少一者界定第六最大鏈輪直徑MD1。 如圖4中所見，第二鏈輪SP2包括鏈輪主體SP2A及複數個鏈輪齒SP2B。複數個鏈輪齒SP2B相對於自行車後鏈輪總成10之旋轉中心軸線A1自鏈輪主體SP2A徑向向外延伸。第二鏈輪SP2之總齒數(至少一個鏈輪齒SP2B之總數目)為45。然而，第二鏈輪SP2之複數個鏈輪齒SP2B之總數目不限於此實施例。 第二鏈輪SP2包括複數個齒底SP2C。齒底SP2C設置於鏈輪齒SP2B中之鄰近兩者之間。複數個齒底SP2C界定具有最大齒底直徑TD2之齒根圓RC2。 如圖5中所見，第三鏈輪SP3包括鏈輪主體SP3A及複數個鏈輪齒SP3B。複數個鏈輪齒SP3B相對於自行車後鏈輪總成10之旋轉中心軸線A1自鏈輪主體SP3A徑向向外延伸。第三鏈輪SP3之總齒數(至少一個鏈輪齒SP3B之總數目)為51。然而，第三鏈輪SP3之複數個鏈輪齒SP3B之總數目不限於此實施例。 第三鏈輪SP3包括複數個齒底SP3C。齒底SP3C設置於鏈輪齒SP3B中之鄰近兩者之間。複數個齒底SP3C界定具有最大齒底直徑TD3之齒根圓RC3。 如圖6中所見，第四鏈輪SP4包括鏈輪主體SP4A及複數個鏈輪齒SP4B。複數個鏈輪齒SP4B相對於自行車後鏈輪總成10之旋轉中心軸線A1自鏈輪主體SP4A徑向向外延伸。第四鏈輪SP4之總齒數(至少一個鏈輪齒SP4B之總數目)為33。然而，第四鏈輪SP4之複數個鏈輪齒SP4B之總數目不限於此實施例。 第四鏈輪SP4包括複數個齒底SP4C。齒底SP4C設置於鏈輪齒SP4B中之鄰近兩者之間。複數個齒底SP4C界定具有最大齒底直徑TD4之齒根圓RC4。第四鏈輪SP4亦可被稱作第五鏈輪構件SP4。鏈輪主體SP4A亦可被稱作第五鏈輪主體SP4A。鏈輪齒SP4B亦可被稱作第五鏈輪齒SP4B。因此，自行車後鏈輪總成10進一步包含第五鏈輪構件SP4。第五鏈輪構件SP4包括第五鏈輪主體SP4A及相對於旋轉中心軸線A1自第五鏈輪主體SP4A徑向向外延伸之複數個第五鏈輪齒SP4B。第五鏈輪構件SP4具有第五最大鏈輪直徑MD4。第五鏈輪齒SP4B中之至少一者界定第五最大鏈輪直徑MD4。第六最大鏈輪直徑MD1大於第五最大鏈輪直徑MD4。 如圖7中所見，第五鏈輪SP5包括鏈輪主體SP5A及複數個鏈輪齒SP5B。複數個鏈輪齒SP5B相對於自行車後鏈輪總成10之旋轉中心軸線A1自鏈輪主體SP5A徑向向外延伸。第五鏈輪SP5之總齒數(至少一個鏈輪齒SP5B之總數目)為28。然而，第五鏈輪SP5之複數個鏈輪齒SP5B之總數目不限於此實施例。 第五鏈輪SP5包括複數個齒底SP5C。齒底SP5C設置於鏈輪齒SP5B中之鄰近兩者之間。複數個齒底SP5C界定具有最大齒底直徑TD5之齒根圓RC5。第五鏈輪SP5亦可被稱作第四鏈輪構件SP5。鏈輪主體SP5A亦可被稱作第四鏈輪主體SP5A。鏈輪齒SP5B亦可被稱作第四鏈輪齒SP5B。因此，自行車後鏈輪總成10進一步包含第四鏈輪構件SP5。第四鏈輪構件SP5包括第四鏈輪主體SP5A及相對於旋轉中心軸線A1自第四鏈輪主體SP5A徑向向外延伸之複數個第四鏈輪齒SP5B。第四鏈輪構件SP5具有第四最大鏈輪直徑MD5。第四鏈輪齒SP5B中之至少一者界定第四最大鏈輪直徑MD5。第五最大鏈輪直徑MD4 (圖6)大於第四最大鏈輪直徑MD5。 如圖8中所見，第六鏈輪SP6包括鏈輪主體SP6A及複數個鏈輪齒SP6B。複數個鏈輪齒SP6B相對於自行車後鏈輪總成10之旋轉中心軸線A1自鏈輪主體SP6A徑向向外延伸。第六鏈輪SP6之總齒數(至少一個鏈輪齒SP6B之總數目)為24。然而，第六鏈輪SP6之複數個鏈輪齒SP6B之總數目不限於此實施例。 第六鏈輪SP6包括複數個齒底SP6C。齒底SP6C設置於鏈輪齒SP6B中之鄰近兩者之間。複數個齒底SP6C界定具有最大齒底直徑TD6之齒根圓RC6。第六鏈輪SP6亦可被稱作第三鏈輪構件SP6。鏈輪主體SP6A亦可被稱作第三鏈輪主體SP6A。鏈輪齒SP6B亦可被稱作第三鏈輪齒SP6B。因此，自行車後鏈輪總成10進一步包含第三鏈輪構件SP6。第三鏈輪構件SP6包括第三鏈輪主體SP6A及相對於旋轉中心軸線A1自第三鏈輪主體SP6A徑向向外延伸之複數個第三鏈輪齒SP6B。第三鏈輪構件SP6具有第三最大鏈輪直徑MD6。第三鏈輪齒SP6B中之至少一者界定第三最大鏈輪直徑MD6。第四鏈輪構件SP5之第四最大鏈輪直徑MD5 (圖7)大於第三最大鏈輪直徑MD6。 如圖9中所見，第七鏈輪SP7包括鏈輪主體SP7A及複數個鏈輪齒SP7B。複數個鏈輪齒SP7B相對於自行車後鏈輪總成10之旋轉中心軸線A1自鏈輪主體SP7A徑向向外延伸。第七鏈輪SP7之總齒數(至少一個鏈輪齒SP7B之總數目)為21。然而，第七鏈輪SP7之複數個鏈輪齒SP7B之總數目不限於此實施例。 第七鏈輪SP7包括複數個齒底SP7C。齒底SP7C設置於鏈輪齒SP7B中之鄰近兩者之間。複數個齒底SP7C界定具有最大齒底直徑TD7之齒根圓RC7。第七鏈輪SP7亦可被稱作第二鏈輪構件SP7。鏈輪主體SP7A亦可被稱作第二鏈輪主體SP7A。鏈輪齒SP7B亦可被稱作第二鏈輪齒SP7B。因此，自行車後鏈輪總成10進一步包含第二鏈輪構件SP7。第二鏈輪構件SP7包括第二鏈輪主體SP7A及相對於旋轉中心軸線A1自第二鏈輪主體SP7A徑向向外延伸之複數個第二鏈輪齒SP7B。第二鏈輪構件SP7具有第二最大鏈輪直徑MD7。第二鏈輪齒SP7B中之至少一者界定第二最大鏈輪直徑MD7。第三最大鏈輪直徑MD6 (圖8)大於第二最大鏈輪直徑MD7。第四最大鏈輪直徑MD5 (圖7)大於第二最大鏈輪直徑MD7。 如圖10中所見，第八鏈輪SP8包括鏈輪主體SP8A及複數個鏈輪齒SP8B。複數個鏈輪齒SP8B相對於自行車後鏈輪總成10之旋轉中心軸線A1自鏈輪主體SP8A徑向向外延伸。第八鏈輪SP8之總齒數(至少一個鏈輪齒SP8B之總數目)為21。然而，第八鏈輪SP8之複數個鏈輪齒SP8B之總數目不限於此實施例。 第八鏈輪SP8包括複數個齒底SP8C。齒底SP8C設置於鏈輪齒SP8B中之鄰近兩者之間。複數個齒底SP8C界定具有最大齒底直徑TD8之齒根圓RC8。第八鏈輪SP8亦可被稱作第一鏈輪構件SP8。鏈輪主體SP8A亦可被稱作第一鏈輪主體SP8A。鏈輪齒SP8B亦可被稱作第一鏈輪齒SP8B。因此，自行車後鏈輪總成10包含第一鏈輪構件SP8。第一鏈輪構件SP8包括第一鏈輪主體SP8A及相對於自行車後鏈輪總成10之旋轉中心軸線A1自第一鏈輪主體SP8A徑向向外延伸之複數個第一鏈輪齒SP8B。第一鏈輪構件SP8具有第一最大鏈輪直徑MD8。第一鏈輪齒SP8B中之至少一者界定第一最大鏈輪直徑MD8。第二最大鏈輪直徑MD7 (圖9)大於第一最大鏈輪直徑MD8。 如圖11中所見，第九鏈輪SP9包括鏈輪主體SP9A及複數個鏈輪齒SP9B。複數個鏈輪齒SP9B相對於自行車後鏈輪總成10之旋轉中心軸線A1自鏈輪主體SP9A徑向向外延伸。第九鏈輪SP9之總齒數(至少一個鏈輪齒SP9B之總數目)為16。然而，第九鏈輪SP9之複數個鏈輪齒SP9B之總數目不限於此實施例。 第九鏈輪SP9包括複數個齒底SP9C。齒底SP9C設置於鏈輪齒SP9B中之鄰近兩者之間。複數個齒底SP9C界定具有最大齒底直徑TD9之齒根圓RC9。 如圖12中所見，第十鏈輪SP10包括鏈輪主體SP10A及複數個鏈輪齒SP10B。複數個鏈輪齒SP10B相對於自行車後鏈輪總成10之旋轉中心軸線A1自鏈輪主體SP10A徑向向外延伸。第十鏈輪SP10之總齒數(至少一個鏈輪齒SP10B之總數目)為14。然而，第十鏈輪SP10之複數個鏈輪齒SP10B之總數目不限於此實施例。 第十鏈輪SP10包括複數個齒底SP10C。齒底SP10C設置於鏈輪齒SP10B中之鄰近兩者之間。複數個齒底SP10C界定具有最大齒底直徑TD10之齒根圓RC10。 如圖13中所見，第十一鏈輪SP11包括鏈輪主體SP11A及複數個鏈輪齒SP11B。複數個鏈輪齒SP11B相對於自行車後鏈輪總成10之旋轉中心軸線A1自鏈輪主體SP11A徑向向外延伸。第十一鏈輪SP11之總齒數(至少一個鏈輪齒SP11B之總數目)為12。然而，第十一鏈輪SP11之複數個鏈輪齒SP11B之總數目不限於此實施例。 第十一鏈輪SP11包括複數個齒底SP11C。齒底SP11C設置於鏈輪齒SP11B中之鄰近兩者之間。複數個齒底SP11C界定具有最大齒底直徑TD11之齒根圓RC11。 如圖14中所見，第十二鏈輪SP12包括鏈輪主體SP12A及複數個鏈輪齒SP12B。複數個鏈輪齒SP12B相對於自行車後鏈輪總成10之旋轉中心軸線A1自鏈輪主體SP12A徑向向外延伸。第十二鏈輪SP12之總齒數(至少一個鏈輪齒SP12B之總數目)為10。然而，第十二鏈輪SP12之複數個鏈輪齒SP12B之總數目不限於此實施例。 第十二鏈輪SP12包括複數個齒底SP12C。齒底SP12C設置於鏈輪齒SP12B中之鄰近兩者之間。複數個齒底SP12C界定具有最大齒底直徑TD12之齒根圓RC12。 如圖15中所見，自行車後鏈輪總成10包含鏈輪托架12。鏈輪托架12為與複數個鏈輪SP分離之構件。如圖2中所見，鏈輪托架12經構形以支撐複數個鏈輪SP中之至少一者。鏈輪SP1及SP4至SP8附接至鏈輪托架12。在此實施例中，鏈輪托架12由鋁製成。然而，鏈輪托架12可由除鋁以外之金屬材料或諸如纖維強化塑膠之非金屬材料製成。 如圖16中所見，該鏈輪托架12包括複數個鏈輪安裝部分14A至14E。複數個鏈輪安裝部分14A至14E中之至少一者具有徑向延伸表面16及軸向延伸表面18。複數個鏈輪安裝部分14A至14E中之至少兩者各自具有相對於旋轉中心軸線A1之徑向延伸表面16及軸向延伸表面18。複數個鏈輪安裝部分14A至14E中之至少兩者相對於旋轉中心軸線A1在徑向方向上彼此鄰近。在此實施例中，複數個鏈輪安裝部分14A至14E各自徑向延伸表面16及軸向延伸表面18。鏈輪安裝部分14A具有徑向延伸表面16A及軸向延伸表面18A。鏈輪安裝部分14B具有徑向延伸表面16B及軸向延伸表面18B。鏈輪安裝部分14C具有徑向延伸表面16C及軸向延伸表面18C。鏈輪安裝部分14D具有徑向延伸表面16D及軸向延伸表面18D。鏈輪安裝部分14E具有徑向延伸表面16E及軸向延伸表面18E。鏈輪安裝部分14E亦可被稱作一級鏈輪安裝部分14E。鏈輪安裝部分14D亦可被稱作二級鏈輪安裝部分14D。鏈輪安裝部分14C亦可被稱作三級鏈輪安裝部分14C。鏈輪安裝部分14B亦可被稱作四級鏈輪安裝部分14B。 徑向延伸表面16A相對於自行車後鏈輪總成10之旋轉中心軸線A1徑向延伸。軸向延伸表面18A相對於旋轉中心軸線A1自徑向延伸表面16A軸向延伸。徑向延伸表面16B相對於自行車後鏈輪總成10之旋轉中心軸線A1徑向延伸。軸向延伸表面18B相對於旋轉中心軸線A1自徑向延伸表面16B軸向延伸。徑向延伸表面16C相對於自行車後鏈輪總成10之旋轉中心軸線A1徑向延伸。軸向延伸表面18C相對於旋轉中心軸線A1自徑向延伸表面16C軸向延伸。徑向延伸表面16D相對於自行車後鏈輪總成10之旋轉中心軸線A1徑向延伸。軸向延伸表面18D相對於旋轉中心軸線A1自徑向延伸表面16D軸向延伸。徑向延伸表面16E相對於自行車後鏈輪總成10之旋轉中心軸線A1徑向延伸。軸向延伸表面18E相對於旋轉中心軸線A1自徑向延伸表面16E軸向延伸。 徑向延伸表面16A亦可被稱作第一徑向延伸表面16A。軸向延伸表面18A亦可被稱作第一軸向延伸表面18A。徑向延伸表面16B亦可被稱作第二徑向延伸表面16B。軸向延伸表面18B亦可被稱作第二軸向延伸表面18B。徑向延伸表面16E亦可被稱作一級徑向延伸表面16E。軸向延伸表面18E亦可被稱作一級軸向延伸表面18E。徑向延伸表面16D亦可被稱作二級徑向延伸表面16D。軸向延伸表面18D亦可被稱作二級軸向延伸表面18D。徑向延伸表面16C亦可被稱作三級徑向延伸表面16C。軸向延伸表面18C亦可被稱作三級軸向延伸表面18C。徑向延伸表面16B亦可被稱作四級徑向延伸表面16B。軸向延伸表面18B亦可被稱作四級軸向延伸表面18B。在此實施例中，軸向延伸表面18垂直於徑向延伸表面16且平行於旋轉中心軸線A1。然而，軸向延伸表面18可相對於徑向延伸表面16及旋轉中心軸線A1中之至少一者傾斜。 換言之，鏈輪托架12包括第一圓周鏈輪安裝部分19A及第二圓周鏈輪安裝部分19B。第一圓周鏈輪安裝部分19A經提供至複數個鏈輪安裝臂22。第二圓周鏈輪安裝部分19B經提供至複數個鏈輪安裝臂22，且相對於旋轉中心軸線A1自第一圓周鏈輪安裝部分19A徑向向內安置。第一圓周鏈輪安裝部分19A經構形以支撐第一鏈輪車輪SP1。第二圓周鏈輪安裝部分19B經構形以支撐第二鏈輪車輪SP4。 如圖17中所見，第一圓周鏈輪安裝部分19A具有第一徑向延伸表面16A及第一軸向延伸表面18A。第一徑向延伸表面16A相對於旋轉中心軸線A1徑向延伸。第一軸向延伸表面18 (18A)相對於旋轉中心軸線A1軸向延伸。在此實施例中，第一圓周鏈輪安裝部分19A具有複數個第一徑向延伸表面16A及複數個第一軸向延伸表面18A。 第二圓周鏈輪安裝部分19B具有第二徑向延伸表面16B及第二軸向延伸表面18B。第二徑向延伸表面16B相對於旋轉中心軸線A1徑向延伸。第二軸向延伸表面18B相對於旋轉中心軸線A1軸向延伸。在此實施例中，第二圓周鏈輪安裝部分19B具有複數個第二徑向延伸表面16B及複數個第二軸向延伸表面18B。 如圖17中所見，複數個鏈輪安裝部分14A至14E相對於旋轉中心軸線A1在徑向方向上彼此偏移。鏈輪安裝部分14A在鏈輪安裝部分14B之徑向外部。鏈輪安裝部分14B在鏈輪安裝部分14C之徑向外部。鏈輪安裝部分14C在鏈輪安裝部分14D之徑向外部。鏈輪安裝部分14D在鏈輪安裝部分14E之徑向外部。鏈輪安裝部分14A至14E係沿鏈輪安裝臂22配置。鏈輪安裝部分14A至14E之配置不限於此實施例。 如圖2中所見，在此實施例中，徑向延伸表面16實質上垂直於旋轉中心軸線A1。然而，徑向延伸表面16可相對於旋轉中心軸線A1傾斜。在此實施例中，軸向延伸表面18實質上平行於旋轉中心軸線A1。然而，軸向延伸表面18可相對於旋轉中心軸線A1傾斜。此外，軸向延伸表面18直接連接至徑向延伸表面16。然而，軸向延伸表面18可與徑向延伸表面16間隔開。 如圖16中所見，鏈輪托架12包括中心部分21及相對於自行車後鏈輪總成10之旋轉中心軸線A1自中心部分21徑向向外延伸之複數個鏈輪安裝臂22。複數個鏈輪安裝部分14A至14E分別提供至複數個鏈輪安裝臂22。在此實施例中，鏈輪安裝部分14A至14E提供至鏈輪安裝臂22。然而，鏈輪安裝部分14A至14E之配置不限於此實施例。 鏈輪托架12之中心部分21具有輪轂嚙合輪廓24。在此實施例中，鏈輪托架12包括經構形以與自行車後輪轂總成H之鏈輪支撐主體H2 (圖2)嚙合的至少十個內部花鍵齒ST。至少十個內部花鍵齒ST相對於自行車後鏈輪總成10之旋轉中心軸線A1在軸向方向D2上延伸，且相對於旋轉中心軸線A1在圓周方向D1上彼此間隔開。 鏈輪托架12包括經安置以在軸向方向D2上鄰近於至少十個內部花鍵齒ST之沿圓周延伸非花鍵部分NS。如圖2中所見，沿圓周延伸非花鍵部分NS相對於旋轉中心軸線A1在徑向方向上自至少十個內部花鍵齒ST凹入。沿圓周延伸非花鍵部分NS在徑向方向上至少自至少十個內部花鍵齒ST之頂峰凹入。在此實施例中，沿圓周延伸非花鍵部分NS經安置以使得至少十個內部花鍵齒ST由沿圓周延伸非花鍵部分NS在軸向方向D2上劃分成至少十個第一內部花鍵齒28及至少十個第二內部花鍵齒31。換言之，輪轂嚙合輪廓24包括第一輪轂內部花鍵26及第二輪轂內部花鍵30。第一輪轂內部花鍵26包括至少十個第一內部花鍵齒28。第二輪轂內部花鍵30包括至少十個第二內部花鍵齒31。 如圖18中所見，沿圓周延伸非花鍵部分NS在圓周方向D1上完全延伸。然而，沿圓周延伸非花鍵部分NS可在圓周方向D1上至少部分地延伸。沿圓周延伸非花鍵部分NS可在圓周方向D1上間歇地延伸。沿圓周延伸非花鍵部分NS包括環形凹槽NS1。 如圖19及圖20中所見，在此實施例中，至少十個內部花鍵齒ST之總數目等於或大於20。至少十個內部花鍵齒ST之總數目等於或小於25。至少十個內部花鍵齒ST之總數目在22至24之範圍內。在此實施例中，至少十個內部花鍵齒ST之總數目為23。然而，至少十個內部花鍵齒ST之總數目不限於此實施例及以上範圍。 如圖19中所見，至少十個第一內部花鍵齒28之總數目等於或大於20。至少十個第一內部花鍵齒28之總數目等於或小於25。至少十個第一內部花鍵齒28之總數目在22至24之範圍內。在此實施例中，至少十個第一內部花鍵齒28之總數目為23。然而，至少十個第一內部花鍵齒28之總數目不限於此實施例及以上範圍。 如圖20中所見，至少十個第二內部花鍵齒31之總數目等於或大於20。至少十個第二內部花鍵齒31之總數目等於或小於25。至少十個第二內部花鍵齒31之總數目在22至24之範圍內。在此實施例中，至少十個第二內部花鍵齒31之總數目為23。然而，至少十個第二內部花鍵齒31之總數目不限於此實施例及以上範圍。 如圖19及圖20中所見，至少十個內部花鍵齒ST中之至少兩個內部花鍵齒相對於自行車後鏈輪總成10之旋轉中心軸線A1以第一內部周節角PA21沿圓周配置。第一內部周節角PA21在13度至17度之範圍內。在此實施例中，第一內部周節角PA21為15度。然而，第一內部周節角PA21不限於此實施例及以上範圍。 如圖19及圖20中所見，至少十個內部花鍵齒ST中之至少其他兩個內部花鍵齒相對於旋轉中心軸線A1以第二內部周節角PA22沿圓周配置。第二內部周節角PA22不同於第一內部周節角PA21。第二內部周節角PA22在28度至32度之範圍內。在此實施例中，第一內部周節角PA21為第二內部周節角PA22之一半。第二內部周節角PA22為30度。然而，第二內部周節角PA22不限於此實施例及以上範圍。第一內部周節角PA21可等於第二內部周節角PA22。 如圖19中所見，至少十個第一內部花鍵齒28中之至少兩個內部花鍵齒相對於自行車後鏈輪總成10之旋轉中心軸線A1以第一內部周節角PA21沿圓周配置。至少十個第一內部花鍵齒28中之至少其他兩個內部花鍵齒相對於旋轉中心軸線A1以第二內部周節角PA22沿圓周配置。 如圖20中所見，至少十個第二內部花鍵齒31中之至少兩個內部花鍵齒相對於自行車後鏈輪總成10之旋轉中心軸線A1以第一內部周節角PA21沿圓周配置。至少十個第二內部花鍵齒31中之至少其他兩個內部花鍵齒相對於旋轉中心軸線A1以第二內部周節角PA22沿圓周配置。 如圖21中所見，至少十個內部花鍵齒ST包括用以在踩踏期間接收來自自行車後輪轂總成H之傳動旋轉力F1的複數個內部花鍵傳動表面ST1。複數個內部花鍵傳動表面ST1各自包括徑向最外邊緣ST1A及徑向最內邊緣ST1B。複數個內部花鍵傳動表面ST1各自包括自徑向最外邊緣ST1A至徑向最內邊緣ST1B界定之徑向長度RL21。徑向長度RL21之總和在11 mm至14 mm之範圍內。徑向長度RL21之總和在12 mm至13 mm之範圍內。在此實施例中，徑向長度之總和為12.5 mm。然而，徑向長度RL21之總和不限於此實施例及以上範圍。 至少十個內部花鍵齒ST具有額外徑向長度RL22。額外徑向長度RL22分別自內部花鍵齒根圓RC22至至少十個內部花鍵齒ST之徑向最內端ST3界定。額外徑向長度RL22之總和在26 mm至29 mm之範圍內。在此實施例中，額外徑向長度RL22之總和為27.6 mm。然而，額外徑向長度RL22之總和不限於此實施例及以上範圍。 至少十個內部花鍵齒ST中之至少一者相對於參考線CL2沿圓周對稱。參考線CL2相對於旋轉中心軸線A1在徑向方向上自旋轉中心軸線A1延伸至至少十個內部花鍵齒ST中之至少一者之徑向最內端ST3的圓周中心點P2。然而，內部花鍵齒ST中之至少一者可具有相對於參考線CL2不對稱的形狀。 內部花鍵傳動表面ST1具有第一內部花鍵表面角AG21。第一內部花鍵表面角AG21界定於內部花鍵傳動表面ST1與第一徑向線L21之間。第一徑向線L21自自行車後鏈輪總成10之旋轉中心軸線A1延伸至內部花鍵傳動表面ST1之徑向最外邊緣ST1A。第一內部周節角PA21或第二內部周節角PA22界定於第一徑向線L21之間。 至少十個內部花鍵齒ST包括內部花鍵非傳動表面ST2。內部花鍵非傳動表面ST2包括徑向最外邊緣ST2A及徑向最內邊緣ST2B。內部花鍵非傳動表面ST2自徑向最外邊緣ST2A延伸至徑向最內邊緣ST2B。內部花鍵非傳動表面ST2具有第二內部花鍵表面角AG22。第二內部花鍵表面角AG22界定於內部花鍵非傳動表面ST2與第二徑向線L22之間。第二徑向線L22自自行車後鏈輪總成10之旋轉中心軸線A1延伸至內部花鍵非傳動表面ST2之徑向最外邊緣ST2A。 在此實施例中，第二內部花鍵表面角AG22等於第一內部花鍵表面角AG21。然而，第一內部花鍵表面角AG21可不同於第二內部花鍵表面角AG22。 第一內部花鍵表面角AG21在0度至6度之範圍內。第二內部花鍵表面角在0度至6度之範圍內。在此實施例中，第一內部花鍵表面角AG21為5度。第二內部花鍵表面角AG22為5度。然而，第一內部花鍵表面角AG21及第二內部花鍵表面角AG22不限於此實施例及以上範圍。 至少十個內部花鍵齒ST分別具有圓周最大寬度MW2。至少十個第一內部花鍵齒28分別具有圓周最大寬度MW2。至少十個第二內部花鍵齒31分別具有圓周最大寬度MW2。圓周最大寬度MW2定義為接收施加至內部花鍵齒ST (第一內部花鍵齒28或第二內部花鍵齒31)之推力F3的最大寬度。至少十個內部花鍵齒ST (第一內部花鍵齒28或第二內部花鍵齒31)之圓周最大寬度MW2之總和可在46 mm至49 mm之範圍內。在此實施例中，至少十個內部花鍵齒ST之圓周最大寬度MW2之總和為47.5 mm。然而，圓周最大寬度MW2之總和不限於此實施例及以上範圍。 如圖2中所見，複數個第一內部花鍵齒28具有在4 mm至5 mm之範圍內的第一軸向長度AL1。在此實施例中，第一軸向長度AL1為4.45 mm。然而，第一軸向長度AL1不限於此實施例及以上範圍。 複數個第二內部花鍵齒31具有在4.5 mm至5.5 mm之範圍內的第二軸向長度AL2。在此實施例中，第二軸向長度AL2為5 mm。第二軸向長度AL2大於第一軸向長度AL1。然而，第二軸向長度AL2不限於此實施例及以上範圍。第二軸向長度AL2可等於或小於第一軸向長度AL1。 沿圓周延伸非花鍵部分NS具有在軸向方向D2上界定之軸向非花鍵長度AL3。軸向非花鍵長度AL3在7 mm至9 mm之範圍內。在此實施例中，軸向非花鍵長度AL3為8 mm。軸向非花鍵長度AL3大於第一軸向長度AL1及第二軸向長度AL2。然而，軸向非花鍵長度AL3不限於此實施例及以上範圍。軸向非花鍵長度AL3可等於或小於第一軸向長度AL1及第二軸向長度AL2中之至少一者。 至少十個內部花鍵齒ST之軸向長度AL4及沿圓周延伸非花鍵部分NS之軸向非花鍵長度AL3的總和在16 mm至21 mm之範圍內。軸向長度AL4為第一軸向長度AL1及第二軸向長度AL2之總和。在此實施例中，至少十個內部花鍵齒ST之軸向長度AL4及沿圓周延伸非花鍵部分NS之軸向非花鍵長度AL3的總和為17.45 mm。至少十個內部花鍵齒ST之軸向長度AL4大於軸向非花鍵長度AL3。然而，軸向長度AL4及軸向非花鍵長度AL3之總和不限於此實施例及以上範圍。至少十個內部花鍵齒ST之軸向長度AL4可等於或小於軸向非花鍵長度AL3。 鏈輪托架12由金屬材料製成。在此實施例中，金屬材料包括鋁。然而，鏈輪托架12可由諸如鐵、鈦、非金屬材料(例如纖維增強塑料)之其他材料製成。 至少十個第一內部花鍵齒28經構形以與自行車後輪轂總成H (圖2)之複數個外部花鍵齒(未展示)嚙合。至少十個第二內部花鍵齒31經構形以與自行車後輪轂總成H (圖2)之複數個外部花鍵齒(未展示)嚙合。第二輪轂內部花鍵30在軸向方向D2上與第一輪轂內部花鍵26間隔開。第二輪轂內部花鍵30可連接至第一輪轂內部花鍵26。然而，輪轂嚙合輪廓24之結構不限於此實施例。輪轂嚙合輪廓24可自鏈輪托架12之中心部分21省略。輪轂嚙合輪廓24可包括代替第一輪轂內部花鍵26及第二輪轂內部花鍵30或除第一輪轂內部花鍵26及第二輪轂內部花鍵30之外的另一結構。 如圖22中所見，自行車後鏈輪總成10進一步包含至少一個緊固構件32。在此實施例中，自行車後鏈輪總成10進一步包含複數個緊固構件32。第一鏈輪SP1藉由複數個緊固構件32緊固至鏈輪托架12。在此實施例中，緊固構件32之總數目為6。然而，緊固構件32之總數目不限於此實施例。緊固構件32較佳由諸如鐵或鈦之金屬材料製成。緊固構件32亦可由鋁製成。然而，至少一個緊固構件32可由非金屬材料製成。在此實施例中，緊固構件32包括鉚釘。然而，緊固構件32可包括代替鉚釘或除鉚釘之外的另一緊固件，諸如黏附劑或擴散結合。 自行車後鏈輪總成10進一步包含至少一個緊固構件34。緊固構件34亦可被稱作緊固件34。亦即，自行車後鏈輪總成10包含至少一個緊固件34。在此實施例中，自行車後鏈輪總成10進一步包含複數個緊固構件(複數個緊固件) 34。第二鏈輪SP2藉由複數個緊固構件(複數個緊固件) 34耦接至第一鏈輪SP1。第三鏈輪車輪(第二鏈輪) SP2經構形以藉由至少一個緊固件(至少一個緊固構件) 34耦接至第一鏈輪車輪(第一鏈輪) SP1。 自行車後鏈輪總成10進一步包含至少一個額外緊固構件36。額外緊固構件36亦可被稱作額外緊固件36。亦即，自行車後鏈輪總成10進一步包含至少一個額外緊固件36。在此實施例中，自行車後鏈輪總成10進一步包含複數個額外緊固構件(複數個額外緊固件) 36。第三鏈輪SP3藉由複數個額外緊固構件36耦接至第二鏈輪SP2。 自行車後鏈輪總成10進一步包含至少一個額外緊固構件38。緊固構件32亦可被稱作第一緊固件32。額外緊固構件38亦可被稱作第二緊固件38。亦即，自行車後鏈輪總成10進一步包含至少一個第一緊固件32及至少一個第二緊固件38。在此實施例中，自行車後鏈輪總成10進一步包含複數個額外緊固構件38。鏈輪SP4藉由複數個額外緊固構件38耦接至鏈輪托架12。額外緊固構件38亦可被稱作第四鏈輪緊固件38。 自行車後鏈輪總成10進一步包含至少一個額外緊固構件40。在此實施例中，自行車後鏈輪總成10進一步包含複數個額外緊固構件40。鏈輪SP5藉由複數個額外緊固構件40耦接至鏈輪托架12。額外緊固構件40亦可被稱作第三鏈輪緊固件40。 自行車後鏈輪總成10進一步包含至少一個額外緊固構件42。額外緊固構件42亦可被稱作第二鏈輪緊固件42。在此實施例中，自行車後鏈輪總成10進一步包含複數個額外緊固構件42。鏈輪SP6藉由複數個額外緊固構件42耦接至鏈輪托架12。 自行車後鏈輪總成10進一步包含至少一個額外緊固構件44。額外緊固構件44亦可被稱作第一鏈輪緊固件44。在此實施例中，自行車後鏈輪總成10進一步包含複數個額外緊固構件44。鏈輪SP7藉由複數個額外緊固構件44耦接至鏈輪托架12。 在此實施例中，緊固構件34之總數目為6。然而，緊固構件34之總數目不限於此實施例。緊固構件34較佳由諸如鐵或鈦之金屬材料製成。緊固構件34亦可由鋁製成。然而，至少一個緊固構件34可由非金屬材料製成。在此實施例中，緊固構件34包括鉚釘。然而，緊固構件34可包括代替鉚釘或除鉚釘之外的另一緊固件，諸如黏附劑或擴散結合。 額外緊固構件36之總數目為6。然而，額外緊固構件36之總數目不限於此實施例。額外緊固構件36較佳由諸如鐵或鈦之金屬材料製成。額外緊固構件36亦可由鋁製成。然而，至少一個額外緊固構件36可由非金屬材料製成。在此實施例中，額外緊固構件36包括鉚釘。然而，額外緊固構件36可包括代替鉚釘或除鉚釘之外的另一緊固件，諸如黏附劑或擴散結合。 額外緊固構件38之總數目為6。額外緊固構件40之總數目為6。額外緊固構件42之總數目為6。額外緊固構件44之總數目為6。然而，額外緊固構件之總數目不限於此實施例。額外緊固構件之材料與緊固構件34及/或額外緊固構件36之材料相同。因此，出於簡潔起見，此處將不再詳細描述。 如圖17中所見，鏈輪安裝部分14A包括設置於徑向延伸表面16A上之安裝孔20A。鏈輪安裝部分14B包括設置於徑向延伸表面16B上之安裝孔20B。鏈輪安裝部分14C包括設置於徑向延伸表面16C上之安裝孔20C。鏈輪安裝部分14D包括設置於徑向延伸表面16D上之安裝孔20D。鏈輪安裝部分14E包括設置於徑向延伸表面16E上之安裝孔20E。如圖2中所見，緊固構件32延伸穿過安裝孔20A。額外緊固構件38延伸穿過安裝孔20B。額外緊固構件40延伸穿過安裝孔20C。額外緊固構件42延伸穿過安裝孔20D。額外緊固構件44延伸穿過安裝孔20E。 如圖3中所見，第一鏈輪SP1具有至少一個圓周耦接點CP1。圓周耦接點CP1亦可被稱作第一圓周耦接點CP1。亦即，第一鏈輪車輪SP1具有至少一個第一圓周耦接點CP1。在此實施例中，至少一個圓周耦接點CP1包括複數個圓周耦接點CP1。圓周耦接點CP1在圓周方向D1上彼此間隔開。圓周耦接點CP1設置於同一徑向位置中，且在圓周方向D1上以恆定節距設置。圓周耦接點CP1之總數目為6。然而，圓周耦接點CP1之總數目不限於此實施例。第一鏈輪SP1包括複數個通孔SP1D。圓周耦接點CP1界定於通孔SP1D之中心處。如圖2中所見，緊固構件32延伸穿過通孔SP1D及安裝孔20A。 如圖22中所見，第一鏈輪SP1在至少一個圓周耦接點CP1處耦接至複數個鏈輪安裝部分14A至14E中之至少一者之徑向延伸表面16 (圖16)。在此實施例中，第一鏈輪SP1在複數個圓周耦接點CP1處耦接至複數個鏈輪安裝部分14A之複數個徑向延伸表面16 (圖16)。第一鏈輪SP1在至少一個圓周耦接點CP1處藉由至少一個緊固構件32耦接至複數個鏈輪安裝部分14A至14E中之至少一者之徑向延伸表面16 (圖16)。第一鏈輪SP1在複數個圓周耦接點CP1處藉由複數個緊固構件32耦接至複數個鏈輪安裝部分14A至14E中之至少一者之徑向延伸表面16。換言之，第一鏈輪車輪SP1在第一圓周耦接點CP1處耦接至第一圓周鏈輪安裝部分19A。第一鏈輪車輪SP1在至少一個第一圓周耦接點CP1處藉由至少一個第一緊固件32耦接至第一圓周鏈輪安裝部分19A。圓周耦接點CP1可由緊固構件(緊固件) 32界定。 如圖4中所見，第二鏈輪SP2具有至少一個額外圓周耦接點CP2。額外圓周耦接點CP2亦可被稱作第三圓周耦接點CP2。亦即，第三鏈輪車輪SP2具有至少一個第三圓周耦接點CP2。在此實施例中，至少一個額外圓周耦接點CP2包括複數個額外圓周耦接點(複數個第三圓周耦接點) CP2。額外圓周耦接點CP2在圓周方向D1上彼此間隔開。額外圓周耦接點CP2設置於同一徑向位置中，且在圓周方向D1上以恆定節距設置。額外圓周耦接點CP2之總數目為12。然而，額外圓周耦接點CP2之總數目不限於此實施例。第二鏈輪SP2包括複數個通孔SP2D。額外圓周耦接點CP2界定於通孔SP2D之中心處。 如圖3中所見，第一鏈輪SP1包括複數個額外通孔SP1E。額外圓周耦接點CP2界定於額外通孔SP1E之中心處。第一鏈輪SP1之額外通孔SP1E設置於對應於第二鏈輪SP2之通孔SP2D (圖4)的位置處。 如圖23中所見，自行車後鏈輪總成10包含在軸向方向D2上設置於鏈輪SP1與SP2之間的複數個間隔件SC1。間隔件SC1包括間隔件孔SC1A。緊固構件34延伸穿過額外通孔SP1E、通孔SP2D及間隔件孔SC1A。間隔件SC1可與緊固構件34一體地形成為整體單件式構件。 如圖22中所見，第二鏈輪SP2在至少一個額外圓周耦接點CP2處耦接至鏈輪托架12及複數個鏈輪SP1至SP12中之一者中的至少一者。在此實施例中，第二鏈輪SP2在至少一個額外圓周耦接點CP2處耦接至複數個鏈輪SP1至SP12中之一者。在此實施例中，第二鏈輪SP2在第一鏈輪SP1處耦接至至少一個額外圓周耦接點CP2。換言之，第三鏈輪車輪SP2在至少一個第三圓周耦接點CP2處耦接至第一鏈輪車輪SP1。然而，第二鏈輪SP2可在另一耦接點處耦接至複數個鏈輪中之一者。第二鏈輪SP2可耦接至鏈輪托架12。 第二鏈輪SP2在至少一個額外圓周耦接點CP2處藉由至少一個緊固構件34耦接至複數個鏈輪SP1至SP12中之一者。第二鏈輪SP2在至少一個額外圓周耦接點CP2處藉由至少一個緊固構件34耦接至第一鏈輪SP1。第二鏈輪SP2在複數個額外圓周耦接點處藉由複數個緊固構件34耦接至複數個鏈輪中之一者。第二鏈輪SP2在複數個額外圓周耦接點CP2處藉由複數個緊固構件34耦接至第一鏈輪SP1。額外圓周耦接點CP2可由緊固構件34界定。 如圖22中所見，至少一個圓周耦接點(至少一個第一圓周耦接點) CP1之總數目不同於至少一個額外圓周耦接點(至少一個第三圓周耦接點) CP2之總數目。在此實施例中，至少一個額外圓周耦接點(至少一個第三圓周耦接點) CP2之總數目大於至少一個圓周耦接點(至少一個第一圓周耦接點) CP1之總數目。圓周耦接點CP1之總數目為6。額外圓周耦接點CP2之總數目為12。至少一個額外圓周耦接點(至少一個第三圓周耦接點) CP2之總數目為至少一個圓周耦接點(至少一個第一圓周耦接點) CP1之總數目的兩倍。至少一個第三圓周耦接點CP2之總數目為至少一個第一圓周耦接點CP1之總數目的兩倍。 然而，至少一個圓周耦接點CP1之總數目與至少一個額外圓周耦接點CP2之總數目之間的關係不限於此實施例。至少一個圓周耦接點CP1之總數目可等於或大於至少一個額外圓周耦接點CP2之總數目。圓周耦接點CP1之總數目不限於此實施例。額外圓周耦接點CP2之總數目不限於此實施例。 複數個額外圓周耦接點CP2之總數目大於複數個鏈輪安裝部分14A之總數目。複數個額外圓周耦接點CP2之總數目大於複數個鏈輪安裝臂22之總數目。然而，複數個額外圓周耦接點CP2之總數目可等於或小於複數個鏈輪安裝部分14A之總數目。複數個額外圓周耦接點CP2之總數目可等於或小於複數個鏈輪安裝臂22之總數目。 如圖5中所見，第三鏈輪SP3具有至少一個額外圓周耦接點CP3。在此實施例中，至少一個額外圓周耦接點CP3包括複數個額外圓周耦接點CP3。額外圓周耦接點CP3在圓周方向D1上彼此間隔開。額外圓周耦接點CP3設置於同一徑向位置中，且在圓周方向D1上以恆定節距設置。額外圓周耦接點CP3之總數目為12。然而，額外圓周耦接點CP3之總數目不限於此實施例。第三鏈輪SP3包括複數個通孔SP3D。額外圓周耦接點CP3界定於通孔SP3D之中心處。 如圖4中所見，第二鏈輪SP2包括複數個額外通孔SP2E。額外圓周耦接點CP3界定於額外通孔SP2E之中心處。第二鏈輪SP2之額外通孔SP2E設置於對應於第三鏈輪SP3之通孔SP3D (圖4)的位置處。 如圖23中所見，自行車後鏈輪總成10包含在軸向方向D2上設置於鏈輪SP2與SP3之間的複數個間隔件SC2。間隔件SC2包括間隔件孔SC2A。額外緊固構件36延伸穿過額外通孔SP2E、通孔SP3D及間隔件孔SC2A。間隔件SC2可與額外緊固構件36一體地形成為整體單件式構件。 如圖22中所見，第三鏈輪SP3在至少一個額外圓周耦接點CP3處耦接至鏈輪托架12及複數個鏈輪SP1至SP12中之一者中的至少一者。在此實施例中，第三鏈輪SP3在至少一個額外圓周耦接點CP3處耦接至複數個鏈輪SP1至SP12中之一者。在此實施例中，第三鏈輪SP3在至少一個額外圓周耦接點CP3處耦接至第二鏈輪SP2。然而，第三鏈輪SP3可在另一耦接點處耦接至複數個鏈輪中之一者。第三鏈輪SP3可耦接至鏈輪托架12。 第三鏈輪SP3在至少一個額外圓周耦接點CP3處藉由至少一個緊固構件36耦接至複數個鏈輪SP1至SP12中之一者。第三鏈輪SP3在至少一個額外圓周耦接點CP3處藉由至少一個緊固構件36耦接至第二鏈輪SP2。第三鏈輪SP3在複數個額外圓周耦接點處藉由複數個額外緊固構件36耦接至複數個鏈輪中之一者。第三鏈輪SP3在複數個額外圓周耦接點CP3處藉由複數個額外緊固構件36耦接至第二鏈輪SP2。換言之，第四鏈輪車輪SP3經構形以藉由至少一個額外緊固件36安裝至第三鏈輪車輪SP2。第四鏈輪車輪SP3經構形以藉由複數個額外緊固件36安裝至第三鏈輪車輪SP2。額外圓周耦接點CP3可由額外緊固構件(額外緊固件) 36界定。 如圖22中所見，至少一個圓周耦接點CP1之總數目不同於至少一個額外圓周耦接點CP3之總數目。在此實施例中，至少一個圓周耦接點CP1之總數目小於至少一個額外圓周耦接點CP3之總數目。圓周耦接點CP1之總數目為6。額外圓周耦接點CP3之總數目為12。至少一個額外圓周耦接點CP3之總數目為至少一個圓周耦接點CP1之總數目的兩倍。然而，至少一個圓周耦接點CP1之總數目與至少一個額外圓周耦接點CP3之總數目之間的關係不限於此實施例。至少一個圓周耦接點CP1之總數目可等於或大於至少一個額外圓周耦接點CP3之總數目。圓周耦接點CP1之總數目不限於此實施例。額外圓周耦接點CP3之總數目不限於此實施例。 複數個額外圓周耦接點CP3之總數目大於複數個鏈輪安裝部分14A之總數目。複數個額外圓周耦接點CP3之總數目大於複數個鏈輪安裝臂22之總數目。然而，複數個額外圓周耦接點CP3之總數目可等於或小於複數個鏈輪安裝部分14A之總數目。複數個額外圓周耦接點CP3之總數目可等於或小於複數個鏈輪安裝臂22之總數目。 如圖6中所見，第四鏈輪SP4具有至少一個第二圓周耦接點CP4。亦即，第二鏈輪車輪SP4具有至少一個第二圓周耦接點CP4。在此實施例中，第二鏈輪車輪SP4包括複數個第二圓周耦接點CP4。第二圓周耦接點CP4在圓周方向D1上彼此間隔開。第二圓周耦接點CP4設置於同一徑向位置中，且在圓周方向D1上以恆定節距設置。第二圓周耦接點CP4之總數目為6。然而，第二圓周耦接點CP4之總數目不限於此實施例。第二鏈輪車輪SP4包括複數個通孔SP4D。第二圓周耦接點CP4界定於通孔SP4D之中心處。如圖2中所見，額外緊固構件38延伸穿過通孔SP4D及安裝孔20B。 如圖22中所見，第二鏈輪車輪SP4在至少一個第二圓周耦接點CP4處耦接至複數個鏈輪安裝部分14A至14E中之至少一者的徑向延伸表面16 (圖16)。在此實施例中，第二鏈輪車輪SP4在複數個第二圓周耦接點CP4處耦接至複數個鏈輪安裝部分14B之複數個徑向延伸表面16B (圖16)。第二鏈輪車輪SP4在複數個第二圓周耦接點CP4處藉由複數個額外緊固構件38耦接至鏈輪安裝部分14B之徑向延伸表面16B (圖16)。換言之，第二鏈輪車輪SP4在至少一個第二圓周耦接點CP4處耦接至第二圓周鏈輪安裝部分19B。第二鏈輪車輪SP4在至少一個第二圓周耦接點CP4處藉由至少一個第二緊固件38耦接至第二圓周鏈輪安裝部分19B。第二鏈輪車輪SP4在複數個第二圓周耦接點CP4處藉由複數個第二緊固件38耦接至第二圓周鏈輪安裝部分19B。額外圓周耦接點(第二圓周耦接點) CP4可由第二緊固件38界定。 至少一個第二圓周耦接點CP4之總數目等於或大於至少一個第一圓周耦接點CP1之總數目。在此實施例中，至少一個第二圓周耦接點CP4之總數目等於至少一個第一圓周耦接點CP1之總數目。然而，至少一個第二圓周耦接點CP4之總數目可小於或大於至少一個第一圓周耦接點CP1之總數目。 第二圓周耦接點CP4設置於圓周耦接點CP1、額外圓周耦接點CP2及額外圓周耦接點CP3之徑向內部。額外圓周耦接點CP2及額外圓周耦接點CP3在圓周耦接點CP1之徑向外部。額外圓周耦接點CP3在圓周耦接點CP1及額外圓周耦接點CP2之徑向外部。額外圓周耦接點CP2及額外圓周耦接點CP3在圓周方向D1上自圓周耦接點CP1及第二圓周耦接點CP4偏移。額外圓周耦接點CP2在圓周方向D1上自額外圓周耦接點CP3偏移。然而，圓周耦接點CP1、額外圓周耦接點CP2、額外圓周耦接點CP3及第二圓周耦接點CP4之配置不限於此實施例。 如圖7中所見，鏈輪SP5包括複數個通孔SP5D。通孔SP5D之總數目為6。然而，通孔SP5D之總數目不限於此實施例。如圖2中所見，額外緊固構件40延伸穿過通孔SP5D及安裝孔20C。 如圖8中所見，鏈輪SP6包括複數個通孔SP6D。通孔SP6D之總數目為6。然而，通孔SP6D之總數目不限於此實施例。如圖2中所見，額外緊固構件42延伸穿過通孔SP6D及安裝孔20D。 如圖9中所見，鏈輪SP7包括複數個通孔SP7D。通孔SP7D之總數目為6。然而，通孔SP7D之總數目不限於此實施例。如圖10中所見，鏈輪SP8包括複數個通孔SP8D。通孔SP8D設置於對應於通孔SP7D之位置處。通孔SP8D之總數目為6。然而，通孔SP8D之總數目不限於此實施例。 如圖2中所見，鏈輪SP7及SP8藉由額外緊固構件42耦接至鏈輪安裝部分14E。自行車後鏈輪總成10包含在軸向方向D2上設置於鏈輪SP7與SP8之間的複數個間隔件SC3。間隔件SC3包括間隔件孔SC3A。額外緊固構件42延伸穿過通孔SP7D、通孔SP8D、安裝孔20E及間隔件孔SC3A。間隔件SC3可與額外緊固構件44一體地形成為整體單件式構件。 如圖11中所見，鏈輪SP9包括內部花鍵SP9S。內部花鍵SP9S包括經構形以與自行車後輪轂總成H (圖2)之複數個外部花鍵齒(未展示)嚙合的複數個內部花鍵齒SP9T。如圖2中所見，在自行車後鏈輪總成10安裝於自行車後輪轂總成H上之狀態中，鏈輪SP9在軸向方向D2上固持於鏈輪托架12之中心部分21與自行車後輪轂總成H之鎖定構件H1之間。 如圖12中所見，鏈輪SP10包括內部花鍵SP10S。內部花鍵SP10S包括經構形以與自行車後輪轂總成H (圖2)之複數個外部花鍵齒(未展示)嚙合的複數個內部花鍵齒SP10T。如圖2中所見，在自行車後鏈輪總成10安裝於自行車後輪轂總成H上之狀態中，鏈輪SP10在軸向方向D2上固持於鏈輪托架12之中心部分21與自行車後輪轂總成H之鎖定構件H1之間。 如圖24中所見，鏈輪SP11包括內部花鍵SP11S。內部花鍵SP11S包括經構形以與自行車後輪轂總成H (圖2)之複數個外部花鍵齒(未展示)嚙合的複數個內部花鍵齒SP11T。如圖2中所見，在自行車後鏈輪總成10安裝於自行車後輪轂總成H上之狀態中，鏈輪SP11在軸向方向D2上固持於鏈輪托架12之中心部分21與自行車後輪轂總成H之鎖定構件H1之間。 如圖25中所見，鏈輪SP12包括扭矩傳遞輪廓SP12F。扭矩傳遞輪廓SP12F包括經構形以與鏈輪SP11嚙合以傳遞旋轉力之複數個外部花鍵齒SP12G。如圖13中所見，鏈輪SP11包括扭矩傳遞輪廓SP11F。扭矩傳遞輪廓SP11F包括經構形以與鏈輪SP12之複數個外部花鍵齒SP12G嚙合以傳遞旋轉力的複數個額外內部花鍵齒SP11G。 如圖2中所見，第一鏈輪構件SP8固定至第二鏈輪構件SP7。第二鏈輪構件SP7固定至複數個鏈輪安裝部分14A至14E中之一級鏈輪安裝部分14E之一級徑向延伸表面16E。第二鏈輪構件SP7在軸向方向D2上相對於旋轉中心軸線A1安置於第一鏈輪構件SP8與一級鏈輪安裝部分14E之一級徑向延伸表面16E之間。第二鏈輪構件SP7藉由第一鏈輪緊固件44固定至一級鏈輪安裝部分14E之一級徑向延伸表面16E。第一鏈輪構件SP8藉由第一鏈輪緊固件44固定至第二鏈輪構件SP7。 在此實施例中，第二鏈輪構件SP7藉由複數個第一鏈輪緊固件44 (圖26)固定至一級鏈輪安裝部分14E之一級徑向延伸表面16E。第一鏈輪構件SP8藉由複數個第一鏈輪緊固件44 (圖26)固定至第二鏈輪構件SP7。然而，第一鏈輪緊固件44之總數目不限於此實施例。第一鏈輪構件SP8可藉由代替第一鏈輪緊固件44或除第一鏈輪緊固件44之外的諸如黏附劑或擴散結合之另一緊固結構固定至第二鏈輪構件SP7。第二鏈輪構件SP7可藉由代替第一鏈輪緊固件44或除第一鏈輪緊固件44之外的諸如黏附劑或擴散結合之另一緊固結構固定至一級鏈輪安裝部分14E之一級徑向延伸表面16E。 第二鏈輪構件SP7與一級鏈輪安裝部分14E之一級徑向延伸表面16E接觸。第一鏈輪構件SP8在軸向方向D2上與一級鏈輪安裝部分14E之一級徑向延伸表面16E間隔開。第二鏈輪構件SP7徑向地面向一級鏈輪安裝部分14E之一級軸向延伸表面18E。第二鏈輪構件SP7可與一級鏈輪安裝部分14E之一級軸向延伸表面18E接觸。 第三鏈輪構件SP6固定至複數個鏈輪安裝部分14A至14E中之二級鏈輪安裝部分14D之二級徑向延伸表面16D。第三鏈輪構件SP6藉由不同於第一鏈輪緊固件44之第二鏈輪緊固件42固定至二級鏈輪安裝部分14D之二級徑向延伸表面16D。第二鏈輪緊固件42為與第一鏈輪緊固件44分離之構件。第二鏈輪緊固件42設置於第一鏈輪緊固件44之徑向外部。 在此實施例中，第三鏈輪構件SP6藉由複數個第二鏈輪緊固件42固定至二級鏈輪安裝部分14D之二級徑向延伸表面16D。然而，第二鏈輪緊固件42之總數目不限於此實施例。第三鏈輪構件SP6可藉由代替第二鏈輪緊固件42或除第二鏈輪緊固件42之外的諸如黏附劑或擴散結合之另一緊固結構固定至二級鏈輪安裝部分14D之二級徑向延伸表面16D。在此實施例中，鏈輪SP6為第三鏈輪構件。然而，鏈輪SP1、SP4及SP5可為第三鏈輪構件。 第二鏈輪構件SP7在軸向方向D2上設置於第一鏈輪構件SP8與第三鏈輪構件SP6之間。第三鏈輪構件SP6與二級鏈輪安裝部分14D之二級徑向延伸表面16D接觸。第二鏈輪構件SP7在軸向方向D2上與二級鏈輪安裝部分14D之二級徑向延伸表面16D間隔開。第三鏈輪構件SP6徑向地面向二級鏈輪安裝部分14D之二級軸向延伸表面18D。第三鏈輪構件SP6可與一級鏈輪安裝部分14E之一級軸向延伸表面18E接觸。 在以上實施例中，第一鏈輪構件SP8藉由第一鏈輪緊固件44固定至第二鏈輪構件SP7，且第二鏈輪構件SP7藉由藉由第一鏈輪緊固件44固定至一級鏈輪安裝部分14E之一級徑向延伸表面16E。然而，第一鏈輪構件SP8及第二鏈輪構件SP7之固定結構可適用於鏈輪SP1與SP4之組合、鏈輪SP4與SP5之組合、鏈輪SP5與SP6之組合及鏈輪SP6與SP7之組合。 第二實施例 下文將參考圖26至圖28描述根據第二實施例之自行車後鏈輪總成210。除了鏈輪托架12以外，自行車後鏈輪總成210具有與自行車後鏈輪總成10之結構及/或構形相同的結構及/或構形。因此，功能與第一實施例中之功能實質上相同的元件在此處將編號相同，且出於簡潔起見，此處將不再詳細描述及/或說明。 如圖26中所見，自行車後鏈輪總成210包含複數個鏈輪SP及鏈輪托架212。第二鏈輪SP2在至少一個額外圓周耦接點CP2處耦接至鏈輪托架212及複數個鏈輪SP1至SP12中之一者中的至少一者。在此實施例中，第二鏈輪SP2在至少一個額外圓周耦接點CP2處耦接至鏈輪托架212。第二鏈輪SP2在複數個額外圓周耦接點CP2處耦接至鏈輪托架212。 自行車後鏈輪總成210進一步包含至少一個緊固構件34。第二鏈輪SP2在至少一個額外圓周耦接點CP2處藉由至少一個緊固構件34耦接至鏈輪托架212。在此實施例中，自行車後鏈輪總成210進一步包含複數個緊固構件34。至少一個額外圓周耦接點CP2包括複數個額外圓周耦接點CP2。第二鏈輪SP2在複數個額外圓周耦接點CP2處藉由複數個緊固構件34耦接至鏈輪托架212。 如圖27中所見，鏈輪托架212之結構與第一實施例之鏈輪托架12之結構實質上相同。在此實施例中，鏈輪托架212包括複數個額外鏈輪安裝部分250。一對額外鏈輪安裝部分250自鏈輪安裝臂22徑向向外延伸。在此實施例中，額外鏈輪安裝部分250之總數目為12。然而，額外鏈輪安裝部分250之總數目不限於此實施例。舉例而言，所述對額外鏈輪安裝部分250可為一個鏈輪安裝部分或至少三個鏈輪安裝部分。第一實施例中之圓周耦接點CP1、額外圓周耦接點CP2、額外圓周耦接點CP3及第二圓周耦接點CP4之配置可應用於此實施例。 如圖28中所見，額外鏈輪安裝部分250在軸向方向D2上設置於鏈輪SP2與SP3之間。額外通孔SP1E自第一鏈輪SP1省略。間隔件SC1及SC2自自行車後鏈輪總成210省略。額外鏈輪安裝部分250包括安裝通孔250A及額外安裝通孔250B。緊固構件34延伸穿過通孔SP2D及安裝通孔250A。額外緊固構件36延伸穿過額外通孔SP2E、通孔SP3D及額外安裝通孔250B。 第三實施例 下文將參考圖29至圖30描述根據第三實施例之自行車後鏈輪總成310。除了鏈輪SP4及SP5之固定結構以外，自行車後鏈輪總成310具有與自行車後鏈輪總成10之結構及/或構形相同的結構及/或構形。因此，功能與上述實施例中之功能實質上相同的元件在此處將編號相同，且出於簡潔起見，此處將不再詳細描述及/或說明。 如圖29中所見，在自行車後鏈輪總成310中，第一鏈輪構件SP8及第二鏈輪構件SP7之固定結構適用於第四鏈輪構件SP5及第五鏈輪構件SP4。具體言之，第四鏈輪構件SP5固定至第五鏈輪構件SP4。第五鏈輪構件SP4固定至複數個鏈輪安裝部分14A至14E中之三級鏈輪安裝部分14C之三級徑向延伸表面16C。第五鏈輪構件SP4藉由第三鏈輪緊固件40固定至三級鏈輪安裝部分14C之三級徑向延伸表面16C。第四鏈輪構件SP5藉由第三鏈輪緊固件40固定至第五鏈輪構件SP4。第三鏈輪緊固件40不同於第一鏈輪緊固件44及第二鏈輪緊固件42。第三鏈輪緊固件40為與第一鏈輪緊固件44及第二鏈輪緊固件42分離之構件。第三鏈輪緊固件40設置於第一鏈輪緊固件44及第二鏈輪緊固件42之徑向外部。 在此實施例中，第五鏈輪構件SP4藉由複數個第三鏈輪緊固件40 (圖30)固定至三級鏈輪安裝部分14C之三級徑向延伸表面16C。第四鏈輪構件SP5藉由複數個第三鏈輪緊固件40 (圖30)固定至第五鏈輪構件SP4。然而，第三鏈輪緊固件40之總數目不限於此實施例。第四鏈輪構件SP5可藉由代替第三鏈輪緊固件40或除第三鏈輪緊固件40之外的諸如黏附劑或擴散結合之另一緊固結構固定至第五鏈輪構件SP4。第五鏈輪構件SP4可藉由代替第三鏈輪緊固件40或除第三鏈輪緊固件40之外的諸如黏附劑或擴散結合之另一緊固結構固定至三級鏈輪安裝部分14C之三級徑向延伸表面16C。 第五鏈輪構件SP4與三級鏈輪安裝部分14C之三級徑向延伸表面16C接觸。第四鏈輪構件SP5在軸向方向D2上與三級鏈輪安裝部分14C之三級徑向延伸表面16C間隔開。第四鏈輪構件SP5及第五鏈輪構件SP4中之每一者徑向地面向三級鏈輪安裝部分14C之三級軸向延伸表面18C。第四鏈輪構件SP5及第五鏈輪構件SP4中之至少一者可與三級鏈輪安裝部分14C之三級軸向延伸表面18C接觸。 自行車後鏈輪總成310包含在軸向方向D2上設置於第四鏈輪構件SP5與第五鏈輪構件SP4之間的複數個間隔件SC4。間隔件SC4包括間隔件孔SC4A。第三鏈輪緊固件40延伸穿過通孔SP4D、通孔SP5D、安裝孔20C及間隔件孔SC4A。間隔件SC4可與第三鏈輪緊固件40一體地形成為整體單件式構件。 第六鏈輪構件SP1代替第一實施例之鏈輪SP4固定至複數個鏈輪安裝部分14A至14E中之四級鏈輪安裝部分14B之四級徑向延伸表面16B。第六鏈輪構件SP1藉由第四鏈輪緊固件38固定至四級鏈輪安裝部分14B之四級徑向延伸表面16B。第四鏈輪緊固件38為與第一鏈輪緊固件44、第二鏈輪緊固件42及第三鏈輪緊固件40分離之構件。第四鏈輪緊固件38設置於第一鏈輪緊固件44、第二鏈輪緊固件42及第三鏈輪緊固件40之徑向外部。 在此實施例中，第六鏈輪構件SP1藉由複數個第四鏈輪緊固件38 (圖30)固定至四級鏈輪安裝部分14B之四級徑向延伸表面16B。然而，第四鏈輪緊固件38之總數目不限於此實施例。第六鏈輪構件SP1可藉由代替第四鏈輪緊固件38或除第四鏈輪緊固件38之外的諸如黏附劑或擴散結合之另一緊固結構固定至四級鏈輪安裝部分14B之四級徑向延伸表面16B。在此實施例中，鏈輪SP1為第六鏈輪構件。然而，鏈輪SP2及SP3可為第六鏈輪構件。 第六鏈輪構件SP1與四級鏈輪安裝部分14B之四級徑向延伸表面16B接觸。第六鏈輪構件SP1徑向地面向四級鏈輪安裝部分14B之軸向延伸表面18B。第六鏈輪構件SP1可與四級鏈輪安裝部分14B之軸向延伸表面18B接觸。 在此實施例中，如圖29中所見，鏈輪SP2代替第一實施例之鏈輪SP1固定至鏈輪安裝部分14A之徑向延伸表面16A。如圖30中所見，鏈輪S3藉由緊固構件34固定至鏈輪SP2。 此外，第二軸向長度AL2小於第一軸向長度AL1。至少十個內部花鍵齒ST之軸向長度AL4小於軸向非花鍵長度AL3。 修改 自行車後鏈輪總成10及210之結構可彼此組合。如圖31之自行車後鏈輪總成310中所見，舉例而言，第二鏈輪SP2在至少一個額外圓周耦接點CP2處耦接至鏈輪托架212及複數個鏈輪SP1至SP12中之一者兩者。第二鏈輪SP2在複數個額外圓周耦接點CP2處藉由複數個緊固構件34耦接至鏈輪托架212及第一鏈輪SP1兩者。 如本文中所使用之術語「包含」及其派生詞意欲為指定所陳述特徵、元件、組件、群組、整數及/或步驟之存在但不排除其他未陳述特徵、元件、組件、群組、整數及/或步驟之存在的開放術語。此概念亦適用於類似含義之詞語，例如術語「具有」、「包括」及其派生詞。 術語「構件」、「區段」、「部分」、「部件」、「元件」、「主體」及「結構」當以單數形式使用時可具有單一部件或複數個部件之雙重含義。 諸如本申請案中敍述的「第一」、「第二」、「一級」及「二級」之序數數目僅為標識符，而不具有任何其他含義，例如特定次序及類似者。此外，例如，術語「第一元件」自身不暗示「第二元件」之存在，且術語「第二元件」自身不暗示「第一元件」之存在。 如本文中所使用之術語「對」可涵蓋除其中成對元件具有彼此相同的形狀或結構之構形外之其中成對元件具有彼此不同的形狀或結構之構形。 因此，術語「一」、「一或多個」及「至少一個」在本文中可互換地使用。 最後，如本文中所使用之諸如「實質上」、「大約」及「大致」之程度術語意謂所修飾之術語之合理量之偏差以使得最終結果並無顯著改變。本申請案中所描述之所有數值可被理解為包括諸如「實質上」、「大約」及「大致」之術語。 顯然，鑒於以上教示，本發明之眾多修改及變化係可能的。因此應理解，在所附申請專利範圍之範疇內，可以不同於如本文中特定描述之方式的其他方式實踐本發明。 This application is a continuation-in-part of U.S. Patent Application Serial No. 15/879,353 filed on January 24, 2018. The content of this application is incorporated herein by reference in its entirety. Embodiments will now be described with reference to the drawings, wherein like reference numerals designate corresponding or identical elements in the various views. First Embodiment Referring first to FIG. 1 , a bicycle rear sprocket assembly 10 according to a first embodiment includes a plurality of sprockets SP. The plurality of sprockets SP includes a first sprocket SP1 and a second sprocket SP2. The plurality of sprockets SP further include a third sprocket SP3 and a fourth sprocket SP4. The plurality of sprockets SP further includes a fifth sprocket SP5 to a twelfth sprocket SP12. In this embodiment, the first sprocket SP1 to the twelfth sprocket SP12 may also be referred to as sprockets SP1 to SP12 respectively. In addition to the sprocket SP1 and the sprocket SP2, the third sprocket SP3 may be any sprocket selected from the plurality of sprockets SP3 to SP12. In addition to sprocket SP1, sprocket SP2 and the sprocket selected as sprocket SP3, the fourth sprocket SP4 can be any sprocket selected from the plurality of sprockets SP3 to SP12. The first sprocket SP1 may also be referred to as a first sprocket wheel SP1. The second sprocket SP2 may also be referred to as a third sprocket wheel SP2. The third sprocket SP3 may also be referred to as a fourth sprocket wheel SP3. The fourth sprocket SP4 may also be referred to as a second sprocket wheel SP4. That is, the bicycle rear sprocket assembly 10 includes a first sprocket wheel SP1 , a second sprocket wheel SP4 and a third sprocket wheel SP2 . The bicycle rear sprocket assembly 10 further includes a fourth sprocket wheel SP3. The first sprocket wheel SP1 may also be referred to as sprocket SP1. The second sprocket wheel SP4 may also be referred to as sprocket SP4. The third sprocket wheel SP2 may also be referred to as sprocket SP2. The fourth sprocket wheel SP3 may also be referred to as sprocket SP3. The total number of sprockets SP1 to SP12 is not limited to this embodiment. As seen in FIG. 1 , the bicycle rear sprocket assembly 10 has a central axis of rotation A1 . The bicycle rear sprocket assembly 10 is rotatably supported by the bicycle rear hub assembly H about a rotation center axis A1 relative to a bicycle frame (not shown). The bicycle rear sprocket assembly 10 is configured to be mounted to the sprocket support body H2 of the bicycle rear hub assembly H (FIG. 2). In this embodiment, the bicycle rear sprocket assembly 10 is fastened to the sprocket support body H2 of the bicycle rear hub assembly H by the locking member H1. The bicycle rear sprocket assembly 10 is configured to mesh with a bicycle chain C to transmit a transmission rotational force F1 between the bicycle chain C and the bicycle rear sprocket assembly 10 during pedaling. During pedaling, the bicycle rear sprocket assembly 10 rotates around the rotation center axis A1 in the transmission rotation direction D11. The transmission rotation direction D11 is defined relative to the rotation center axis A1 of the bicycle rear sprocket assembly 10 along the circumferential direction D1. The counter-rotational direction D12 is the opposite direction of the drive rotation direction D11 and is defined along the circumferential direction D1. In this embodiment, the sprocket SP3 is the largest sprocket in the rear sprocket assembly 10 of the bicycle. The twelfth sprocket SP12 is the smallest sprocket in the rear sprocket assembly 10 of the bicycle. The first sprocket SP1 has a maximum tooth bottom diameter TD1. The maximum tooth bottom diameter TD1 can also be referred to as the first maximum tooth bottom diameter TD1 . That is, the first sprocket wheel SP1 has a first maximum tooth bottom diameter TD1. The second sprocket SP2 has an additional maximum tooth bottom diameter TD2 greater than the maximum tooth bottom diameter TD1 of the first sprocket SP1. The additional maximum tooth bottom diameter TD2 may also be referred to as the third maximum tooth bottom diameter TD2. That is, the third sprocket wheel SP2 has a third maximum tooth bottom diameter TD2 that is larger than the first maximum tooth bottom diameter TD1 of the first sprocket wheel SP1 . The second sprocket wheel SP4 has a second maximum tooth bottom diameter TD4 smaller than the first maximum tooth bottom diameter TD1 of the first sprocket wheel SP1 . The third sprocket SP3 has an additional maximum tooth bottom diameter TD3 greater than the maximum tooth bottom diameter TD1 of the first sprocket SP1. The sprockets SP5 to SP12 have a fifth largest tooth bottom diameter TD5 to a twelfth largest tooth bottom diameter TD12 , respectively. The dimensional relationship among the sprockets SP1 to SP12 is not limited to this embodiment. For example, the additional maximum tooth bottom diameter TD2 may be equal to or smaller than the maximum tooth bottom diameter TD1 of the first sprocket SP1. The second maximum tooth bottom diameter TD4 may be equal to or greater than the first maximum tooth bottom diameter TD1 of the first sprocket wheel SP1. As seen in FIG. 2 , the first sprocket wheel SP1 is disposed between the second sprocket wheel SP4 and the third sprocket wheel SP2 with respect to the rotation center axis A1 in the axial direction D2 . The third sprocket wheel SP2 is arranged between the first sprocket wheel SP1 and the fourth sprocket wheel SP3 in the axial direction D2. The second sprocket SP2 is adjacent to the first sprocket SP1 in the axial direction D2 with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10, and there is no other sprocket between the first sprocket SP1 and the second sprocket SP2. a sprocket. The third sprocket SP3 is adjacent to the second sprocket SP2 in the axial direction D2 with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . And there is no other sprocket between the second sprocket SP2 and the third sprocket SP3. The fourth sprocket SP4 is adjacent to the first sprocket SP1 in the axial direction D2 with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10, and there is no other sprocket between the first sprocket SP1 and the fourth sprocket SP4. a sprocket. The third sprocket SP3, the second sprocket SP2, the first sprocket SP1, and the fourth sprocket SP4 to the twelfth sprocket SP12 are arranged in this order in the axial direction D2. In this embodiment, the sprockets SP1 to SP12 are separate members from each other. However, at least two of the sprockets SP1 to SP12 may be provided at least partially integrally with each other. Specifically, at least two of the sprockets SP1 to SP12 may be integrally provided as a unitary one-piece member. Alternatively, at least two of the sprockets SP1 to SP12 may be connected to each other by at least one mechanical fastener such as a rivet or by adhesive, diffusion bonding or the like. The sprockets SP1 to SP12 are made of metal material. In this embodiment, the first sprocket SP1 is made of titanium. The second sprocket SP2 is made of aluminum. The third sprocket SP3 is made of aluminum. The fourth sprocket SP4 is made of titanium. However, the materials of the first sprocket SP1 to the twelfth sprocket SP12 are not limited to this embodiment. At least one of the sprockets SP1 to SP12 may be made of another metal material or non-metal material. As seen in FIG. 3 , the first sprocket SP1 includes a sprocket body SP1A and a plurality of sprocket teeth SP1B. A plurality of sprocket teeth SP1B extend radially outward from the sprocket main body SP1A with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The total number of teeth of the first sprocket SP1 (the total number of at least one sprocket tooth SP1B) is 39. However, the total number of the sprocket teeth SP1B of the first sprocket SP1 is not limited to this embodiment. The first sprocket SP1 includes a plurality of tooth bottoms SP1C. The tooth base SP1C is disposed between adjacent two of the sprocket teeth SP1B. The plurality of tooth bottoms SP1C define a dedendum circle RC1 having a maximum tooth bottom diameter TD1. As used herein, the term "maximum tooth root diameter" is intended to be the diameter of the root circle defined by the tooth bottoms if all the tooth bottoms are of the same shape as each other, or is intended to be the diameter of the tooth bottom having several shapes arranged in one The diameter of the largest dedendum circle defined by at least one tooth base in a sprocket such that a plurality of dedendum circles are defined in the sprocket. Definitions of terms are applicable to any of the first sprocket SP1 to the twelfth sprocket SP12. The first sprocket SP1 may also be referred to as a sixth sprocket member SP1. The sprocket main body SP1A may also be referred to as a sixth sprocket main body SP1A. The sprocket SP1B may also be referred to as a sixth sprocket SP1B. Therefore, the bicycle rear sprocket assembly 10 further includes a sixth sprocket member SP1. The sixth sprocket member SP1 includes a sixth sprocket body SP1A and a plurality of sixth sprocket teeth SP1B extending radially outward from the sixth sprocket body SP1A relative to the rotation center axis A1. The sixth sprocket member SP1 has a sixth largest sprocket diameter MD1. At least one of the sixth sprocket teeth SP1B defines a sixth maximum sprocket diameter MD1 . As seen in FIG. 4 , the second sprocket SP2 includes a sprocket body SP2A and a plurality of sprocket teeth SP2B. A plurality of sprocket teeth SP2B extend radially outward from the sprocket main body SP2A with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The total number of teeth of the second sprocket SP2 (total number of at least one sprocket tooth SP2B) is 45. However, the total number of sprocket teeth SP2B of the second sprocket SP2 is not limited to this embodiment. The second sprocket SP2 includes a plurality of tooth bottoms SP2C. The tooth base SP2C is disposed between adjacent two of the sprocket teeth SP2B. The plurality of tooth bottoms SP2C define a dedendum circle RC2 having a maximum tooth bottom diameter TD2. As seen in FIG. 5 , the third sprocket SP3 includes a sprocket body SP3A and a plurality of sprocket teeth SP3B. A plurality of sprocket teeth SP3B extend radially outward from the sprocket main body SP3A with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The total number of teeth of the third sprocket SP3 (total number of at least one sprocket tooth SP3B) is 51. However, the total number of sprocket teeth SP3B of the third sprocket SP3 is not limited to this embodiment. The third sprocket SP3 includes a plurality of tooth bottoms SP3C. The tooth base SP3C is disposed between adjacent two of the sprocket teeth SP3B. The plurality of tooth bottoms SP3C define a dedendum circle RC3 having a maximum tooth bottom diameter TD3. As seen in FIG. 6 , the fourth sprocket SP4 includes a sprocket body SP4A and a plurality of sprocket teeth SP4B. A plurality of sprocket teeth SP4B extend radially outward from the sprocket main body SP4A with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The total number of teeth of the fourth sprocket SP4 (total number of at least one sprocket tooth SP4B) is 33. However, the total number of sprocket teeth SP4B of the fourth sprocket SP4 is not limited to this embodiment. The fourth sprocket SP4 includes a plurality of tooth bottoms SP4C. The tooth bottoms SP4C are disposed between adjacent ones of the sprocket teeth SP4B. The plurality of tooth bottoms SP4C define a dedendum circle RC4 having a maximum tooth bottom diameter TD4. The fourth sprocket SP4 may also be referred to as a fifth sprocket member SP4. The sprocket body SP4A may also be referred to as the fifth sprocket body SP4A. The sprocket SP4B may also be referred to as fifth sprocket SP4B. Therefore, the bicycle rear sprocket assembly 10 further includes a fifth sprocket member SP4. The fifth sprocket member SP4 includes a fifth sprocket body SP4A and a plurality of fifth sprocket teeth SP4B extending radially outward from the fifth sprocket body SP4A relative to the rotation center axis A1. Fifth sprocket member SP4 has a fifth largest sprocket diameter MD4. At least one of fifth sprocket teeth SP4B defines a fifth maximum sprocket diameter MD4. The sixth largest sprocket diameter MD1 is greater than the fifth largest sprocket diameter MD4. As seen in FIG. 7 , the fifth sprocket SP5 includes a sprocket body SP5A and a plurality of sprocket teeth SP5B. A plurality of sprocket teeth SP5B extend radially outward from the sprocket main body SP5A with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The total number of teeth of the fifth sprocket SP5 (total number of at least one sprocket tooth SP5B) is 28. However, the total number of sprocket teeth SP5B of the fifth sprocket SP5 is not limited to this embodiment. The fifth sprocket SP5 includes a plurality of tooth bottoms SP5C. The tooth base SP5C is disposed between adjacent two of the sprocket teeth SP5B. The plurality of tooth bottoms SP5C define a dedendum circle RC5 having a maximum tooth bottom diameter TD5. The fifth sprocket SP5 may also be referred to as a fourth sprocket member SP5. The sprocket main body SP5A may also be referred to as a fourth sprocket main body SP5A. The sprocket SP5B may also be referred to as a fourth sprocket SP5B. Therefore, the bicycle rear sprocket assembly 10 further includes the fourth sprocket member SP5. The fourth sprocket member SP5 includes a fourth sprocket main body SP5A and a plurality of fourth sprocket teeth SP5B extending radially outward from the fourth sprocket main body SP5A relative to the rotation central axis A1. The fourth sprocket member SP5 has a fourth largest sprocket diameter MD5. At least one of the fourth sprocket teeth SP5B defines a fourth maximum sprocket diameter MD5. The fifth largest sprocket diameter MD4 (FIG. 6) is greater than the fourth largest sprocket diameter MD5. As seen in FIG. 8 , the sixth sprocket SP6 includes a sprocket body SP6A and a plurality of sprocket teeth SP6B. A plurality of sprocket teeth SP6B extend radially outward from the sprocket main body SP6A with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The total number of teeth of the sixth sprocket SP6 (total number of at least one sprocket tooth SP6B) is 24. However, the total number of the sprocket teeth SP6B of the sixth sprocket SP6 is not limited to this embodiment. The sixth sprocket SP6 includes a plurality of tooth bottoms SP6C. The tooth base SP6C is disposed between adjacent two of the sprocket teeth SP6B. The plurality of tooth bottoms SP6C define a dedendum circle RC6 having a maximum tooth bottom diameter TD6. The sixth sprocket SP6 may also be referred to as a third sprocket member SP6. The sprocket main body SP6A may also be referred to as a third sprocket main body SP6A. The sprocket SP6B may also be referred to as a third sprocket SP6B. Therefore, the bicycle rear sprocket assembly 10 further includes the third sprocket member SP6. The third sprocket member SP6 includes a third sprocket main body SP6A and a plurality of third sprocket teeth SP6B extending radially outward from the third sprocket main body SP6A relative to the rotation center axis A1. The third sprocket member SP6 has a third largest sprocket diameter MD6. At least one of the third sprocket teeth SP6B defines a third maximum sprocket diameter MD6. The fourth largest sprocket diameter MD5 (FIG. 7) of the fourth sprocket member SP5 is larger than the third largest sprocket diameter MD6. As seen in FIG. 9 , the seventh sprocket SP7 includes a sprocket body SP7A and a plurality of sprocket teeth SP7B. A plurality of sprocket teeth SP7B extend radially outward from the sprocket main body SP7A with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The total number of teeth of the seventh sprocket SP7 (the total number of at least one sprocket tooth SP7B) is 21. However, the total number of sprocket teeth SP7B of the seventh sprocket SP7 is not limited to this embodiment. The seventh sprocket SP7 includes a plurality of tooth bottoms SP7C. The tooth base SP7C is disposed between adjacent ones of the sprocket teeth SP7B. The plurality of tooth bottoms SP7C define a dedendum circle RC7 having a maximum tooth bottom diameter TD7. The seventh sprocket SP7 may also be referred to as a second sprocket member SP7. The sprocket main body SP7A may also be referred to as a second sprocket main body SP7A. The sprocket SP7B may also be referred to as the second sprocket SP7B. Therefore, the bicycle rear sprocket assembly 10 further includes the second sprocket member SP7. The second sprocket member SP7 includes a second sprocket main body SP7A and a plurality of second sprocket teeth SP7B extending radially outward from the second sprocket main body SP7A relative to the rotation center axis A1. The second sprocket member SP7 has a second largest sprocket diameter MD7. At least one of the second sprocket teeth SP7B defines a second maximum sprocket diameter MD7. The third largest sprocket diameter MD6 (FIG. 8) is greater than the second largest sprocket diameter MD7. The fourth largest sprocket diameter MD5 (FIG. 7) is greater than the second largest sprocket diameter MD7. As seen in FIG. 10 , the eighth sprocket SP8 includes a sprocket body SP8A and a plurality of sprocket teeth SP8B. A plurality of sprocket teeth SP8B extend radially outward from the sprocket body SP8A with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The total number of teeth of the eighth sprocket SP8 (total number of at least one sprocket tooth SP8B) is twenty-one. However, the total number of sprocket teeth SP8B of the eighth sprocket SP8 is not limited to this embodiment. The eighth sprocket SP8 includes a plurality of tooth bottoms SP8C. The bottoms SP8C are disposed between adjacent ones of the sprocket teeth SP8B. The plurality of tooth bottoms SP8C define a dedendum circle RC8 having a maximum tooth bottom diameter TD8. The eighth sprocket SP8 may also be referred to as the first sprocket member SP8. The sprocket main body SP8A may also be referred to as a first sprocket main body SP8A. The sprocket SP8B may also be referred to as the first sprocket SP8B. Accordingly, the bicycle rear sprocket assembly 10 includes the first sprocket member SP8. The first sprocket member SP8 includes a first sprocket body SP8A and a plurality of first sprocket teeth SP8B extending radially outward from the first sprocket body SP8A relative to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The first sprocket member SP8 has a first maximum sprocket diameter MD8. At least one of the first sprocket teeth SP8B defines a first maximum sprocket diameter MD8. The second largest sprocket diameter MD7 (FIG. 9) is greater than the first largest sprocket diameter MD8. As seen in FIG. 11 , the ninth sprocket SP9 includes a sprocket body SP9A and a plurality of sprocket teeth SP9B. A plurality of sprocket teeth SP9B extend radially outward from the sprocket main body SP9A with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The total number of teeth of the ninth sprocket SP9 (total number of at least one sprocket tooth SP9B) is sixteen. However, the total number of sprocket teeth SP9B of the ninth sprocket SP9 is not limited to this embodiment. The ninth sprocket SP9 includes a plurality of tooth bottoms SP9C. The bottoms SP9C are disposed between adjacent ones of the sprocket teeth SP9B. The plurality of tooth bottoms SP9C define a dedendum circle RC9 having a maximum tooth bottom diameter TD9. As seen in FIG. 12 , the tenth sprocket SP10 includes a sprocket body SP10A and a plurality of sprocket teeth SP10B. A plurality of sprocket teeth SP10B extend radially outward from the sprocket main body SP10A with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The total number of teeth of the tenth sprocket SP10 (the total number of at least one sprocket tooth SP10B) is fourteen. However, the total number of sprocket teeth SP10B of the tenth sprocket SP10 is not limited to this embodiment. The tenth sprocket SP10 includes a plurality of tooth bottoms SP10C. The tooth bottoms SP10C are disposed between adjacent ones of the sprocket teeth SP10B. The plurality of tooth bottoms SP10C define a dedendum circle RC10 having a maximum tooth bottom diameter TD10. As seen in FIG. 13 , the eleventh sprocket SP11 includes a sprocket body SP11A and a plurality of sprocket teeth SP11B. A plurality of sprocket teeth SP11B extend radially outward from the sprocket main body SP11A with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The total number of teeth of the eleventh sprocket SP11 (total number of at least one sprocket SP11B) is twelve. However, the total number of sprocket teeth SP11B of the eleventh sprocket SP11 is not limited to this embodiment. The eleventh sprocket SP11 includes a plurality of tooth bottoms SP11C. The tooth bottom SP11C is disposed between adjacent two of the sprocket teeth SP11B. The plurality of tooth bottoms SP11C define a dedendum circle RC11 having a maximum tooth bottom diameter TD11. As seen in FIG. 14 , the twelfth sprocket SP12 includes a sprocket body SP12A and a plurality of sprocket teeth SP12B. A plurality of sprocket teeth SP12B extend radially outward from the sprocket main body SP12A relative to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The total number of teeth of the twelfth sprocket SP12 (total number of at least one sprocket tooth SP12B) is ten. However, the total number of sprocket teeth SP12B of the twelfth sprocket SP12 is not limited to this embodiment. The twelfth sprocket SP12 includes a plurality of tooth bottoms SP12C. The tooth bottoms SP12C are disposed between adjacent ones of the sprocket teeth SP12B. The plurality of tooth bottoms SP12C define a dedendum circle RC12 having a maximum tooth bottom diameter TD12. As seen in FIG. 15 , the bicycle rear sprocket assembly 10 includes a sprocket carrier 12 . The sprocket bracket 12 is a separate member from the sprockets SP. As seen in FIG. 2 , the sprocket carrier 12 is configured to support at least one of the plurality of sprockets SP. The sprockets SP1 and SP4 to SP8 are attached to the sprocket carrier 12 . In this embodiment, the sprocket carrier 12 is made of aluminum. However, the sprocket carrier 12 may be made of a metallic material other than aluminum or a non-metallic material such as fiber reinforced plastic. As seen in FIG. 16, the sprocket bracket 12 includes a plurality of sprocket mounting portions 14A to 14E. At least one of the plurality of sprocket mounting portions 14A- 14E has a radially extending surface 16 and an axially extending surface 18 . At least two of the plurality of sprocket mounting portions 14A to 14E each have a radially extending surface 16 and an axially extending surface 18 relative to the rotation center axis A1. At least two of the plurality of sprocket mounting portions 14A to 14E are adjacent to each other in the radial direction with respect to the rotation center axis A1. In this embodiment, the plurality of sprocket mounting portions 14A to 14E each have a radially extending surface 16 and an axially extending surface 18 . The sprocket mounting portion 14A has a radially extending surface 16A and an axially extending surface 18A. The sprocket mounting portion 14B has a radially extending surface 16B and an axially extending surface 18B. The sprocket mounting portion 14C has a radially extending surface 16C and an axially extending surface 18C. The sprocket mounting portion 14D has a radially extending surface 16D and an axially extending surface 18D. The sprocket mounting portion 14E has a radially extending surface 16E and an axially extending surface 18E. The sprocket mounting portion 14E may also be referred to as a primary sprocket mounting portion 14E. The sprocket mounting portion 14D may also be referred to as a secondary sprocket mounting portion 14D. The sprocket mounting portion 14C may also be referred to as a third-stage sprocket mounting portion 14C. The sprocket mounting portion 14B may also be referred to as a four-stage sprocket mounting portion 14B. The radially extending surface 16A extends radially with respect to the central axis of rotation A1 of the bicycle rear sprocket assembly 10 . The axially extending surface 18A axially extends from the radially extending surface 16A with respect to the rotation center axis A1. The radially extending surface 16B extends radially with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . The axially extending surface 18B axially extends from the radially extending surface 16B with respect to the rotation center axis A1. The radially extending surface 16C extends radially with respect to the central axis of rotation A1 of the bicycle rear sprocket assembly 10 . The axially extending surface 18C axially extends from the radially extending surface 16C relative to the rotation center axis A1. The radially extending surface 16D extends radially with respect to the central axis of rotation A1 of the bicycle rear sprocket assembly 10 . The axially extending surface 18D axially extends from the radially extending surface 16D with respect to the rotation center axis A1. The radially extending surface 16E extends radially with respect to the central axis of rotation A1 of the bicycle rear sprocket assembly 10 . The axially extending surface 18E axially extends from the radially extending surface 16E with respect to the rotation center axis A1. The radially extending surface 16A may also be referred to as a first radially extending surface 16A. The axially extending surface 18A may also be referred to as a first axially extending surface 18A. The radially extending surface 16B may also be referred to as a second radially extending surface 16B. The axially extending surface 18B may also be referred to as the second axially extending surface 18B. The radially extending surface 16E may also be referred to as a primary radially extending surface 16E. The axially extending surface 18E may also be referred to as a primary axially extending surface 18E. The radially extending surface 16D may also be referred to as a secondary radially extending surface 16D. The axially extending surface 18D may also be referred to as a secondary axially extending surface 18D. The radially extending surface 16C may also be referred to as a tertiary radially extending surface 16C. The axially extending surface 18C may also be referred to as a tertiary axially extending surface 18C. The radially-extending surface 16B may also be referred to as a four-stage radially-extending surface 16B. The axially extending surface 18B may also be referred to as a four-level axially extending surface 18B. In this embodiment, the axially extending surface 18 is perpendicular to the radially extending surface 16 and parallel to the rotation center axis A1. However, the axially extending surface 18 may be inclined with respect to at least one of the radially extending surface 16 and the rotation center axis A1. In other words, the sprocket bracket 12 includes a first circumferential sprocket mounting portion 19A and a second circumferential sprocket mounting portion 19B. The first circumferential sprocket mounting portion 19A is provided to a plurality of sprocket mounting arms 22 . The second circumferential sprocket mounting portion 19B is provided to the plurality of sprocket mounting arms 22 and is disposed radially inward from the first circumferential sprocket mounting portion 19A with respect to the rotation center axis A1. The first circumferential sprocket mounting portion 19A is configured to support the first sprocket wheel SP1. The second circumferential sprocket mounting portion 19B is configured to support the second sprocket wheel SP4. As seen in FIG. 17 , the first circumferential sprocket mounting portion 19A has a first radially extending surface 16A and a first axially extending surface 18A. The first radially extending surface 16A extends radially with respect to the rotation center axis A1. The first axially extending surface 18 (18A) axially extends with respect to the rotation center axis A1. In this embodiment, the first circumferential sprocket mounting portion 19A has a plurality of first radially extending surfaces 16A and a plurality of first axially extending surfaces 18A. The second circumferential sprocket mounting portion 19B has a second radially extending surface 16B and a second axially extending surface 18B. The second radially extending surface 16B extends radially with respect to the rotation center axis A1. The second axially extending surface 18B extends axially with respect to the rotation center axis A1. In this embodiment, the second circumferential sprocket mounting portion 19B has a plurality of second radially extending surfaces 16B and a plurality of second axially extending surfaces 18B. As seen in FIG. 17 , the plurality of sprocket mounting portions 14A to 14E are offset from each other in the radial direction with respect to the rotation center axis A1 . The sprocket mounting portion 14A is radially outward of the sprocket mounting portion 14B. The sprocket mounting portion 14B is radially outward of the sprocket mounting portion 14C. The sprocket mounting portion 14C is radially outward of the sprocket mounting portion 14D. The sprocket mounting portion 14D is radially outward of the sprocket mounting portion 14E. The sprocket mounting portions 14A to 14E are arranged along the sprocket mounting arm 22 . The configuration of the sprocket mounting portions 14A to 14E is not limited to this embodiment. As seen in FIG. 2 , in this embodiment, the radially extending surface 16 is substantially perpendicular to the central axis of rotation A1 . However, the radially extending surface 16 may be inclined relative to the rotation center axis A1. In this embodiment, the axially extending surface 18 is substantially parallel to the rotation center axis A1. However, the axially extending surface 18 may be inclined with respect to the rotation center axis A1. Furthermore, the axially extending surface 18 is directly connected to the radially extending surface 16 . However, the axially extending surface 18 may be spaced apart from the radially extending surface 16 . As seen in FIG. 16 , the sprocket bracket 12 includes a central portion 21 and a plurality of sprocket mounting arms 22 extending radially outward from the central portion 21 with respect to the central axis of rotation A1 of the bicycle rear sprocket assembly 10 . A plurality of sprocket mounting portions 14A to 14E are respectively provided to a plurality of sprocket mounting arms 22 . In this embodiment, the sprocket mounting portions 14A to 14E are provided to the sprocket mounting arm 22 . However, the configuration of the sprocket mounting portions 14A to 14E is not limited to this embodiment. The central portion 21 of the sprocket carrier 12 has a hub engaging profile 24 . In this embodiment, the sprocket carrier 12 includes at least ten internal spline teeth ST configured to engage with the sprocket support body H2 of the bicycle rear hub assembly H ( FIG. 2 ). At least ten internal spline teeth ST extend in the axial direction D2 with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 and are spaced apart from each other in the circumferential direction D1 with respect to the rotation center axis A1 . The sprocket carrier 12 includes a circumferentially extending non-splined portion NS disposed adjacent to at least ten inner spline teeth ST in the axial direction D2. As seen in FIG. 2 , the circumferentially extending non-spline portion NS is recessed from at least ten inner spline teeth ST in a radial direction with respect to the central axis of rotation A1 . The circumferentially extending non-splined portion NS is recessed in radial direction at least from the crests of the at least ten inner spline teeth ST. In this embodiment, the circumferentially extending non-spline portion NS is arranged such that the at least ten inner spline teeth ST are divided in the axial direction D2 by the circumferentially extending non-spline portion NS into at least ten first inner spline teeth ST. spline teeth 28 and at least ten second inner spline teeth 31 . In other words, the hub engagement profile 24 includes a first hub internal spline 26 and a second hub internal spline 30 . The first hub internal spline 26 includes at least ten first internal spline teeth 28 . The second hub internal spline 30 includes at least ten second internal spline teeth 31 . As seen in FIG. 18, the circumferentially extending non-spline portion NS is completely extended in the circumferential direction D1. However, the circumferentially extending non-splined portion NS may extend at least partially in the circumferential direction D1. The circumferentially extending non-spline portion NS may extend intermittently in the circumferential direction D1. The circumferentially extending non-splined portion NS comprises an annular groove NS1. As seen in FIGS. 19 and 20 , the total number of at least ten internal spline teeth ST is equal to or greater than 20 in this embodiment. The total number of at least ten internal spline teeth ST is equal to or less than 25. The total number of at least ten internal spline teeth ST is in the range of 22-24. In this embodiment, the total number of at least ten internal spline teeth ST is twenty-three. However, the total number of at least ten internal spline teeth ST is not limited to this embodiment and the above range. As seen in FIG. 19 , the total number of at least ten first internal spline teeth 28 is equal to or greater than twenty. The total number of at least ten first internal spline teeth 28 is equal to or less than twenty-five. The total number of at least ten first internal spline teeth 28 is in the range of 22-24. In this embodiment, the total number of at least ten first internal spline teeth 28 is twenty-three. However, the total number of at least ten first internal spline teeth 28 is not limited to this embodiment and the above range. As seen in FIG. 20 , the total number of at least ten second internal spline teeth 31 is equal to or greater than twenty. The total number of at least ten second internal spline teeth 31 is equal to or less than twenty-five. The total number of at least ten second internal spline teeth 31 is in the range of 22-24. In this embodiment, the total number of at least ten second internal spline teeth 31 is twenty-three. However, the total number of at least ten second internal spline teeth 31 is not limited to this embodiment and the above range. As seen in FIGS. 19 and 20 , at least two of the at least ten internal spline teeth ST are along the circumference at a first internal circumferential pitch angle PA21 with respect to the rotation center axis A1 of the rear sprocket assembly 10 of the bicycle. configuration. The first inner circumferential pitch angle PA21 is in the range of 13 degrees to 17 degrees. In this embodiment, the first inner circumferential pitch angle PA21 is 15 degrees. However, the first internal pitch angle PA21 is not limited to this embodiment and the above range. As seen in FIGS. 19 and 20 , at least two other internal spline teeth among the at least ten internal spline teeth ST are circumferentially arranged at the second internal circumferential pitch angle PA22 with respect to the rotation central axis A1 . The second inner circumferential pitch angle PA22 is different from the first inner circumferential pitch angle PA21. The second inner circumferential pitch angle PA22 is in the range of 28 degrees to 32 degrees. In this embodiment, the first internal pitch angle PA21 is half of the second internal pitch angle PA22. The second inner circumferential pitch angle PA22 is 30 degrees. However, the second inner circumferential pitch angle PA22 is not limited to this embodiment and the above range. The first inner circumferential pitch angle PA21 may be equal to the second inner circumferential pitch angle PA22. As seen in FIG. 19, at least two of the at least ten first internal spline teeth 28 are circumferentially arranged at a first internal circumferential pitch angle PA21 with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10. . At least two other internal spline teeth of the at least ten first internal spline teeth 28 are circumferentially arranged at a second internal circumferential pitch angle PA22 with respect to the rotation central axis A1 . As seen in FIG. 20 , at least two of the at least ten second internal spline teeth 31 are circumferentially arranged at a first internal circumferential pitch angle PA21 with respect to the rotation center axis A1 of the bicycle rear sprocket assembly 10 . At least two other internal spline teeth of the at least ten second internal spline teeth 31 are circumferentially arranged at a second internal circumferential pitch angle PA22 with respect to the rotation central axis A1. As seen in FIG. 21 , the at least ten internal spline teeth ST include a plurality of internal spline transmission surfaces ST1 for receiving the transmission rotational force F1 from the bicycle rear hub assembly H during pedaling. Each of the plurality of inner splined transmission surfaces ST1 includes a radially outermost edge ST1A and a radially innermost edge ST1B. Each of the plurality of inner splined transmission surfaces ST1 includes a radial length RL21 defined from a radially outermost edge ST1A to a radially innermost edge ST1B. The sum of the radial lengths RL21 is in the range of 11 mm to 14 mm. The sum of the radial lengths RL21 is in the range of 12 mm to 13 mm. In this example, the sum of the radial lengths is 12.5 mm. However, the sum of the radial lengths RL21 is not limited to this embodiment and the above range. At least ten internal spline teeth ST have an additional radial length RL22. The additional radial length RL22 is defined from the inner spline root circle RC22 to the radially innermost end ST3 of at least ten inner spline teeth ST, respectively. The sum of the additional radial lengths RL22 is in the range of 26 mm to 29 mm. In this embodiment, the sum of the additional radial lengths RL22 is 27.6 mm. However, the sum of the additional radial lengths RL22 is not limited to this embodiment and the above range. At least one of the at least ten internal spline teeth ST is circumferentially symmetrical with respect to the reference line CL2. The reference line CL2 extends in the radial direction relative to the rotation center axis A1 from the rotation center axis A1 to the circumferential center point P2 of the radially innermost end ST3 of at least one of the at least ten internal spline teeth ST. However, at least one of the inner spline teeth ST may have an asymmetrical shape with respect to the reference line CL2. The inner splined transmission surface ST1 has a first inner splined surface angle AG21. A first internal spline surface angle AG21 is defined between the internal spline transmission surface ST1 and the first radial line L21. The first radial line L21 extends from the rotation central axis A1 of the bicycle rear sprocket assembly 10 to the radially outermost edge ST1A of the inner spline transmission surface ST1. The first inner circumferential pitch angle PA21 or the second inner circumferential pitch angle PA22 is defined between the first radial lines L21. At least ten internal spline teeth ST comprise internal spline non-drive surfaces ST2. The inner splined non-drive surface ST2 comprises a radially outermost edge ST2A and a radially innermost edge ST2B. The inner splined non-drive surface ST2 extends from a radially outermost edge ST2A to a radially innermost edge ST2B. The internal splined non-drive surface ST2 has a second internal splined surface angle AG22. A second internal spline surface angle AG22 is defined between the internal spline non-drive surface ST2 and the second radial line L22. The second radial line L22 extends from the rotation center axis A1 of the bicycle rear sprocket assembly 10 to the radially outermost edge ST2A of the inner splined non-transmission surface ST2. In this embodiment, the second internal spline surface angle AG22 is equal to the first internal spline surface angle AG21. However, the first internal spline surface angle AG21 may be different than the second internal spline surface angle AG22. The first internal spline surface angle AG21 is in the range of 0° to 6°. The second internal spline surface angle is in the range of 0 degrees to 6 degrees. In this embodiment, the first internal spline surface angle AG21 is 5 degrees. The second internal spline surface angle AG22 is 5 degrees. However, the first internal spline surface angle AG21 and the second internal spline surface angle AG22 are not limited to this embodiment and the above range. At least ten internal spline teeth ST each have a maximum circumferential width MW2. At least ten first internal spline teeth 28 each have a circumferential maximum width MW2. At least ten second inner spline teeth 31 each have a circumferential maximum width MW2. The circumferential maximum width MW2 is defined as the maximum width receiving the thrust F3 applied to the inner spline teeth ST (the first inner spline teeth 28 or the second inner spline teeth 31 ). The sum of the circumferential maximum width MW2 of at least ten internal spline teeth ST (the first internal spline tooth 28 or the second internal spline tooth 31 ) may be in the range of 46 mm to 49 mm. In this embodiment, the sum of the circumferential maximum width MW2 of at least ten internal spline teeth ST is 47.5 mm. However, the sum of the maximum circumferential widths MW2 is not limited to this embodiment and the above range. As seen in Figure 2, the first plurality of internal spline teeth 28 has a first axial length AL1 in the range of 4 mm to 5 mm. In this embodiment, the first axial length AL1 is 4.45 mm. However, the first axial length AL1 is not limited to this embodiment and the above range. The plurality of second internal spline teeth 31 has a second axial length AL2 in the range of 4.5 mm to 5.5 mm. In this embodiment, the second axial length AL2 is 5 mm. The second axial length AL2 is greater than the first axial length AL1. However, the second axial length AL2 is not limited to this embodiment and the above range. The second axial length AL2 may be equal to or smaller than the first axial length AL1. The circumferentially extending non-splined portion NS has an axial non-splined length AL3 defined in the axial direction D2. The axial non-spline length AL3 is in the range of 7 mm to 9 mm. In this embodiment, the axial non-spline length AL3 is 8 mm. The axial non-spline length AL3 is greater than the first axial length AL1 and the second axial length AL2 . However, the axial non-spline length AL3 is not limited to this embodiment and the above range. The axial non-spline length AL3 may be equal to or less than at least one of the first axial length AL1 and the second axial length AL2. The sum of the axial length AL4 of the at least ten internal spline teeth ST and the axial non-spline length AL3 of the circumferentially extending non-spline portion NS is in the range of 16 mm to 21 mm. The axial length AL4 is the sum of the first axial length AL1 and the second axial length AL2. In this embodiment, the sum of the axial length AL4 of the at least ten internal spline teeth ST and the axial non-spline length AL3 of the circumferentially extending non-spline portion NS is 17.45 mm. The axial length AL4 of at least ten internal spline teeth ST is greater than the axial non-spline length AL3. However, the sum of the axial length AL4 and the axial non-spline length AL3 is not limited to this embodiment and the above range. The axial length AL4 of the at least ten internal spline teeth ST may be equal to or less than the axial non-spline length AL3. The sprocket carrier 12 is made of metal material. In this embodiment, the metal material includes aluminum. However, the sprocket carrier 12 may be made of other materials such as iron, titanium, non-metallic materials such as fiber reinforced plastic. At least ten first internal spline teeth 28 are configured to mesh with a plurality of external spline teeth (not shown) of the bicycle rear hub assembly H ( FIG. 2 ). At least ten second inner spline teeth 31 are configured to mesh with a plurality of outer spline teeth (not shown) of the bicycle rear hub assembly H ( FIG. 2 ). The second hub internal splines 30 are spaced apart from the first hub internal splines 26 in the axial direction D2. The second hub internal spline 30 is connectable to the first hub internal spline 26 . However, the structure of the hub engagement profile 24 is not limited to this embodiment. The hub engaging profile 24 may be omitted from the central portion 21 of the sprocket carrier 12 . The hub engagement profile 24 may include another structure in place of or in addition to the first hub internal splines 26 and the second hub internal splines 30 . As seen in FIG. 22 , the bicycle rear sprocket assembly 10 further includes at least one fastening member 32 . In this embodiment, the bicycle rear sprocket assembly 10 further includes a plurality of fastening members 32 . The first sprocket SP1 is fastened to the sprocket bracket 12 by a plurality of fastening members 32 . In this embodiment, the total number of fastening members 32 is six. However, the total number of fastening members 32 is not limited to this embodiment. Fastening member 32 is preferably made of a metal material such as iron or titanium. The fastening member 32 can also be made of aluminum. However, at least one fastening member 32 may be made of a non-metallic material. In this embodiment, the fastening members 32 comprise rivets. However, the fastening member 32 may include another fastener instead of or in addition to the rivet, such as an adhesive or diffusion bonding. The bicycle rear sprocket assembly 10 further includes at least one fastening member 34 . The fastening member 34 may also be referred to as a fastener 34 . That is, the bicycle rear sprocket assembly 10 includes at least one fastener 34 . In this embodiment, the bicycle rear sprocket assembly 10 further includes a plurality of fastening members (a plurality of fasteners) 34 . The second sprocket SP2 is coupled to the first sprocket SP1 through a plurality of fastening members (a plurality of fasteners) 34 . The third sprocket wheel (second sprocket) SP2 is configured to be coupled to the first sprocket wheel (first sprocket) SP1 by at least one fastener (at least one fastening member) 34 . The bicycle rear sprocket assembly 10 further includes at least one additional fastening member 36 . The additional fastening member 36 may also be referred to as an additional fastener 36 . That is, the bicycle rear sprocket assembly 10 further includes at least one additional fastener 36 . In this embodiment, the bicycle rear sprocket assembly 10 further includes a plurality of additional fastening members (a plurality of additional fasteners) 36 . The third sprocket SP3 is coupled to the second sprocket SP2 through a plurality of additional fastening members 36 . The bicycle rear sprocket assembly 10 further includes at least one additional fastening member 38 . The fastening member 32 may also be referred to as a first fastener 32 . The additional fastening member 38 may also be referred to as a second fastener 38 . That is, the bicycle rear sprocket assembly 10 further includes at least one first fastener 32 and at least one second fastener 38 . In this embodiment, the bicycle rear sprocket assembly 10 further includes a plurality of additional fastening members 38 . The sprocket SP4 is coupled to the sprocket bracket 12 by a plurality of additional fastening members 38 . The additional fastening member 38 may also be referred to as a fourth sprocket fastening member 38 . The bicycle rear sprocket assembly 10 further includes at least one additional fastening member 40 . In this embodiment, the bicycle rear sprocket assembly 10 further includes a plurality of additional fastening members 40 . The sprocket SP5 is coupled to the sprocket bracket 12 by a plurality of additional fastening members 40 . The additional fastening member 40 may also be referred to as a third sprocket fastening member 40 . The bicycle rear sprocket assembly 10 further includes at least one additional fastening member 42 . The additional fastening member 42 may also be referred to as a second sprocket fastening member 42 . In this embodiment, the bicycle rear sprocket assembly 10 further includes a plurality of additional fastening members 42 . The sprocket SP6 is coupled to the sprocket bracket 12 by a plurality of additional fastening members 42 . The bicycle rear sprocket assembly 10 further includes at least one additional fastening member 44 . The additional fastening member 44 may also be referred to as the first sprocket fastening member 44 . In this embodiment, the bicycle rear sprocket assembly 10 further includes a plurality of additional fastening members 44 . The sprocket SP7 is coupled to the sprocket bracket 12 by a plurality of additional fastening members 44 . In this embodiment, the total number of fastening members 34 is six. However, the total number of fastening members 34 is not limited to this embodiment. Fastening member 34 is preferably made of a metallic material such as iron or titanium. The fastening member 34 can also be made of aluminum. However, at least one fastening member 34 may be made of a non-metallic material. In this embodiment, the fastening members 34 comprise rivets. However, the fastening member 34 may include another fastener instead of or in addition to the rivet, such as an adhesive or diffusion bonding. The total number of additional fastening members 36 is six. However, the total number of additional fastening members 36 is not limited to this embodiment. The additional fastening member 36 is preferably made of a metal material such as iron or titanium. The additional fastening member 36 can also be made of aluminum. However, at least one additional fastening member 36 may be made of a non-metallic material. In this embodiment, the additional fastening members 36 comprise rivets. However, the additional fastening member 36 may comprise another fastener instead of or in addition to a rivet, such as an adhesive or a diffusion bond. The total number of additional fastening members 38 is six. The total number of additional fastening members 40 is six. The total number of additional fastening members 42 is six. The total number of additional fastening members 44 is six. However, the total number of additional fastening members is not limited to this embodiment. The material of the additional fastening member is the same as the material of the fastening member 34 and/or the additional fastening member 36 . Therefore, for the sake of brevity, no detailed description will be given here. As seen in FIG. 17, sprocket mounting portion 14A includes mounting holes 20A disposed in radially extending surface 16A. The sprocket mounting portion 14B includes mounting holes 20B disposed on the radially extending surface 16B. The sprocket mounting portion 14C includes mounting holes 20C disposed in the radially extending surface 16C. The sprocket mounting portion 14D includes mounting holes 20D disposed in the radially extending surface 16D. Sprocket mounting portion 14E includes mounting holes 20E disposed in radially extending surface 16E. As seen in FIG. 2 , the fastening member 32 extends through the mounting hole 20A. An additional fastening member 38 extends through the mounting hole 20B. The additional fastening member 40 extends through the mounting hole 20C. An additional fastening member 42 extends through the mounting hole 20D. An additional fastening member 44 extends through the mounting hole 20E. As seen in FIG. 3 , the first sprocket SP1 has at least one circumferential coupling point CP1 . The circumferential coupling point CP1 can also be referred to as the first circumferential coupling point CP1. That is, the first sprocket wheel SP1 has at least one first circumferential coupling point CP1. In this embodiment, at least one circumferential coupling point CP1 includes a plurality of circumferential coupling points CP1. The circumferential coupling points CP1 are spaced apart from each other in the circumferential direction D1. The circumferential coupling points CP1 are arranged in the same radial position and arranged at a constant pitch in the circumferential direction D1. The total number of circumferential coupling points CP1 is six. However, the total number of circumferential coupling points CP1 is not limited to this embodiment. The first sprocket SP1 includes a plurality of through holes SP1D. The circumferential coupling point CP1 is defined at the center of the via SP1D. As seen in FIG. 2 , the fastening member 32 extends through the through hole SP1D and the mounting hole 20A. As seen in FIG. 22 , the first sprocket SP1 is coupled at at least one circumferential coupling point CP1 to the radially extending surface 16 ( FIG. 16 ) of at least one of the plurality of sprocket mounting portions 14A-14E. In this embodiment, the first sprocket SP1 is coupled to the plurality of radially extending surfaces 16 of the plurality of sprocket mounting portions 14A at the plurality of circumferential coupling points CP1 ( FIG. 16 ). The first sprocket SP1 is coupled by at least one fastening member 32 to the radially extending surface 16 of at least one of the plurality of sprocket mounting portions 14A-14E at at least one circumferential coupling point CP1 ( FIG. 16 ). The first sprocket SP1 is coupled to the radially extending surface 16 of at least one of the sprocket mounting portions 14A to 14E at the circumferential coupling points CP1 by the fastening members 32 . In other words, the first sprocket wheel SP1 is coupled to the first circumferential sprocket mounting portion 19A at the first circumferential coupling point CP1. The first sprocket wheel SP1 is coupled to the first circumferential sprocket mounting portion 19A at at least one first circumferential coupling point CP1 by at least one first fastener 32 . The circumferential coupling point CP1 may be defined by a fastening member (fastener) 32 . As seen in Fig. 4, the second sprocket SP2 has at least one additional circumferential coupling point CP2. The additional circumferential coupling point CP2 may also be referred to as a third circumferential coupling point CP2. That is, the third sprocket wheel SP2 has at least one third circumferential coupling point CP2. In this embodiment, at least one additional circumferential coupling point CP2 includes a plurality of additional circumferential coupling points (a plurality of third circumferential coupling points) CP2. The additional circumferential coupling points CP2 are spaced apart from each other in the circumferential direction D1. The additional circumferential coupling points CP2 are arranged in the same radial position and at a constant pitch in the circumferential direction D1. The total number of additional circumferential coupling points CP2 is twelve. However, the total number of additional circumferential coupling points CP2 is not limited to this embodiment. The second sprocket SP2 includes a plurality of through holes SP2D. An additional circumferential coupling point CP2 is defined at the center of the via SP2D. As seen in FIG. 3 , the first sprocket SP1 includes a plurality of additional through holes SP1E. An additional circumferential coupling point CP2 is defined at the center of the additional via SP1E. The additional through hole SP1E of the first sprocket SP1 is provided at a position corresponding to the through hole SP2D ( FIG. 4 ) of the second sprocket SP2. As seen in FIG. 23 , the bicycle rear sprocket assembly 10 includes a plurality of spacers SC1 disposed between the sprockets SP1 and SP2 in the axial direction D2. The spacer SC1 includes a spacer hole SC1A. The fastening member 34 extends through the additional through hole SP1E, the through hole SP2D, and the spacer hole SC1A. The spacer SC1 may be integrally formed with the fastening member 34 as an integral one-piece member. As seen in FIG. 22, the second sprocket SP2 is coupled to at least one of the sprocket carrier 12 and one of the plurality of sprockets SP1-SP12 at at least one additional circumferential coupling point CP2. In this embodiment, the second sprocket SP2 is coupled to one of the plurality of sprockets SP1 to SP12 at at least one additional circumferential coupling point CP2. In this embodiment, the second sprocket SP2 is coupled to at least one additional circumferential coupling point CP2 at the first sprocket SP1. In other words, the third sprocket wheel SP2 is coupled to the first sprocket wheel SP1 at at least one third circumferential coupling point CP2. However, the second sprocket SP2 may be coupled to one of the plurality of sprockets at another coupling point. The second sprocket SP2 may be coupled to the sprocket carrier 12 . The second sprocket SP2 is coupled to one of the plurality of sprockets SP1 to SP12 by at least one fastening member 34 at at least one additional circumferential coupling point CP2. The second sprocket SP2 is coupled to the first sprocket SP1 by at least one fastening member 34 at at least one additional circumferential coupling point CP2. The second sprocket SP2 is coupled to one of the plurality of sprockets by a plurality of fastening members 34 at a plurality of additional circumferential coupling points. The second sprocket SP2 is coupled to the first sprocket SP1 by a plurality of fastening members 34 at a plurality of additional circumferential coupling points CP2. The additional circumferential coupling point CP2 may be defined by the fastening member 34 . As seen in FIG. 22, the total number of at least one circumferential coupling point (at least one first circumferential coupling point) CP1 is different from the total number of at least one additional circumferential coupling point (at least one third circumferential coupling point) CP2. In this embodiment, the total number of at least one additional circumferential coupling point (at least one third circumferential coupling point) CP2 is greater than the total number of at least one circumferential coupling point (at least one first circumferential coupling point) CP1. The total number of circumferential coupling points CP1 is six. The total number of additional circumferential coupling points CP2 is twelve. The total number of at least one additional circumferential coupling point (at least one third circumferential coupling point) CP2 is twice the total number of at least one circumferential coupling point (at least one first circumferential coupling point) CP1. The total number of the at least one third circumferential coupling point CP2 is twice the total number of the at least one first circumferential coupling point CP1 . However, the relationship between the total number of at least one circumferential coupling point CP1 and the total number of at least one additional circumferential coupling point CP2 is not limited to this embodiment. The total number of at least one circumferential coupling point CP1 may be equal to or greater than the total number of at least one additional circumferential coupling point CP2. The total number of circumferential coupling points CP1 is not limited to this embodiment. The total number of additional circumferential coupling points CP2 is not limited to this embodiment. The total number of the plurality of extra circumferential coupling points CP2 is greater than the total number of the plurality of sprocket mounting portions 14A. The total number of the plurality of extra circumferential coupling points CP2 is greater than the total number of the plurality of sprocket mounting arms 22 . However, the total number of the plurality of additional circumferential coupling points CP2 may be equal to or smaller than the total number of the plurality of sprocket mounting portions 14A. The total number of the plurality of additional circumferential coupling points CP2 may be equal to or less than the total number of the plurality of sprocket mounting arms 22 . As seen in Fig. 5, the third sprocket SP3 has at least one additional circumferential coupling point CP3. In this embodiment, at least one additional circumferential coupling point CP3 includes a plurality of additional circumferential coupling points CP3. The additional circumferential coupling points CP3 are spaced apart from each other in the circumferential direction D1. The additional circumferential coupling points CP3 are arranged in the same radial position and at a constant pitch in the circumferential direction D1. The total number of additional circumferential coupling points CP3 is twelve. However, the total number of additional circumferential coupling points CP3 is not limited to this embodiment. The third sprocket SP3 includes a plurality of through holes SP3D. An additional circumferential coupling point CP3 is defined at the center of the via SP3D. As seen in FIG. 4, the second sprocket SP2 includes a plurality of additional through holes SP2E. An additional circumferential coupling point CP3 is defined at the center of the additional via SP2E. The additional through hole SP2E of the second sprocket SP2 is provided at a position corresponding to the through hole SP3D (FIG. 4) of the third sprocket SP3. As seen in FIG. 23 , the bicycle rear sprocket assembly 10 includes a plurality of spacers SC2 disposed between the sprockets SP2 and SP3 in the axial direction D2. The spacer SC2 includes a spacer hole SC2A. The additional fastening member 36 extends through the additional through hole SP2E, the through hole SP3D and the spacer hole SC2A. The spacer SC2 may be integrally formed with the additional fastening member 36 as a unitary one-piece member. As seen in FIG. 22, the third sprocket SP3 is coupled to at least one of the sprocket carrier 12 and one of the plurality of sprockets SP1-SP12 at at least one additional circumferential coupling point CP3. In this embodiment, the third sprocket SP3 is coupled to one of the plurality of sprockets SP1 to SP12 at at least one additional circumferential coupling point CP3. In this embodiment, the third sprocket SP3 is coupled to the second sprocket SP2 at at least one additional circumferential coupling point CP3. However, the third sprocket SP3 may be coupled to one of the plurality of sprockets at another coupling point. The third sprocket SP3 may be coupled to the sprocket carrier 12 . The third sprocket SP3 is coupled to one of the plurality of sprockets SP1 to SP12 by at least one fastening member 36 at at least one additional circumferential coupling point CP3. The third sprocket SP3 is coupled to the second sprocket SP2 by at least one fastening member 36 at at least one additional circumferential coupling point CP3. The third sprocket SP3 is coupled to one of the sprockets by means of additional fastening members 36 at additional circumferential coupling points. The third sprocket SP3 is coupled to the second sprocket SP2 at a plurality of additional circumferential coupling points CP3 by a plurality of additional fastening members 36 . In other words, the fourth sprocket wheel SP3 is configured to be mounted to the third sprocket wheel SP2 by at least one additional fastener 36 . The fourth sprocket wheel SP3 is configured to be mounted to the third sprocket wheel SP2 by a plurality of additional fasteners 36 . The additional circumferential coupling point CP3 may be defined by an additional fastening member (additional fastener) 36 . As seen in FIG. 22 , the total number of at least one circumferential coupling point CP1 is different from the total number of at least one additional circumferential coupling point CP3 . In this embodiment, the total number of at least one circumferential coupling point CP1 is smaller than the total number of at least one additional circumferential coupling point CP3. The total number of circumferential coupling points CP1 is six. The total number of additional circumferential coupling points CP3 is twelve. The total number of at least one additional circumferential coupling point CP3 is twice the total number of at least one circumferential coupling point CP1 . However, the relationship between the total number of at least one circumferential coupling point CP1 and the total number of at least one additional circumferential coupling point CP3 is not limited to this embodiment. The total number of at least one circumferential coupling point CP1 may be equal to or greater than the total number of at least one additional circumferential coupling point CP3. The total number of circumferential coupling points CP1 is not limited to this embodiment. The total number of additional circumferential coupling points CP3 is not limited to this embodiment. The total number of the plurality of extra circumferential coupling points CP3 is greater than the total number of the plurality of sprocket mounting portions 14A. The total number of the plurality of extra circumferential coupling points CP3 is greater than the total number of the plurality of sprocket mounting arms 22 . However, the total number of the plurality of extra circumferential coupling points CP3 may be equal to or smaller than the total number of the plurality of sprocket mounting portions 14A. The total number of the plurality of additional circumferential coupling points CP3 may be equal to or less than the total number of the plurality of sprocket mounting arms 22 . As seen in FIG. 6 , the fourth sprocket SP4 has at least one second circumferential coupling point CP4 . That is, the second sprocket wheel SP4 has at least one second circumferential coupling point CP4. In this embodiment, the second sprocket wheel SP4 includes a plurality of second circumferential coupling points CP4. The second circumferential coupling points CP4 are spaced apart from each other in the circumferential direction D1. The second circumferential coupling points CP4 are arranged in the same radial position and arranged at a constant pitch in the circumferential direction D1. The total number of the second circumferential coupling points CP4 is six. However, the total number of the second circumferential coupling points CP4 is not limited to this embodiment. The second sprocket wheel SP4 includes a plurality of through holes SP4D. The second circumferential coupling point CP4 is defined at the center of the via SP4D. As seen in FIG. 2 , the additional fastening member 38 extends through the through hole SP4D and the mounting hole 20B. As seen in FIG. 22, the second sprocket wheel SP4 is coupled to the radially extending surface 16 of at least one of the plurality of sprocket mounting portions 14A to 14E at at least one second circumferential coupling point CP4 (FIG. 16) . In this embodiment, the second sprocket wheel SP4 is coupled to the plurality of radially extending surfaces 16B of the plurality of sprocket mounting portions 14B at the plurality of second circumferential coupling points CP4 ( FIG. 16 ). The second sprocket wheel SP4 is coupled to the radially extending surface 16B of the sprocket mounting portion 14B by a plurality of additional fastening members 38 at a plurality of second circumferential coupling points CP4 ( FIG. 16 ). In other words, the second sprocket wheel SP4 is coupled to the second circumferential sprocket mounting portion 19B at at least one second circumferential coupling point CP4. The second sprocket wheel SP4 is coupled to the second circumferential sprocket mounting portion 19B at at least one second circumferential coupling point CP4 by at least one second fastener 38 . The second sprocket wheel SP4 is coupled to the second circumferential sprocket mounting portion 19B at the plurality of second circumferential coupling points CP4 by the plurality of second fasteners 38 . An additional circumferential coupling point (second circumferential coupling point) CP4 may be defined by a second fastener 38 . The total number of at least one second circumferential coupling point CP4 is equal to or greater than the total number of at least one first circumferential coupling point CP1 . In this embodiment, the total number of at least one second circumferential coupling point CP4 is equal to the total number of at least one first circumferential coupling point CP1 . However, the total number of at least one second circumferential coupling point CP4 may be less than or greater than the total number of at least one first circumferential coupling point CP1. The second circumferential coupling point CP4 is disposed radially inside the circumferential coupling point CP1 , the additional circumferential coupling point CP2 and the additional circumferential coupling point CP3 . The additional circumferential coupling point CP2 and the additional circumferential coupling point CP3 are radially outside the circumferential coupling point CP1. The additional circumferential coupling point CP3 is radially outside of the circumferential coupling point CP1 and the additional circumferential coupling point CP2. The additional circumferential coupling point CP2 and the additional circumferential coupling point CP3 are offset from the circumferential coupling point CP1 and the second circumferential coupling point CP4 in the circumferential direction D1. The additional circumferential coupling point CP2 is offset from the additional circumferential coupling point CP3 in the circumferential direction D1. However, the arrangement of the circumferential coupling point CP1 , the additional circumferential coupling point CP2 , the additional circumferential coupling point CP3 and the second circumferential coupling point CP4 is not limited to this embodiment. As seen in FIG. 7, the sprocket SP5 includes a plurality of through holes SP5D. The total number of vias SP5D is six. However, the total number of vias SP5D is not limited to this embodiment. As seen in FIG. 2 , the additional fastening member 40 extends through the through hole SP5D and the mounting hole 20C. As seen in FIG. 8, the sprocket SP6 includes a plurality of through holes SP6D. The total number of vias SP6D is six. However, the total number of vias SP6D is not limited to this embodiment. As seen in FIG. 2 , the additional fastening member 42 extends through the through hole SP6D and the mounting hole 20D. As seen in FIG. 9, the sprocket SP7 includes a plurality of through holes SP7D. The total number of vias SP7D is six. However, the total number of via holes SP7D is not limited to this embodiment. As seen in FIG. 10, the sprocket SP8 includes a plurality of through holes SP8D. The through hole SP8D is provided at a position corresponding to the through hole SP7D. The total number of vias SP8D is six. However, the total number of vias SP8D is not limited to this embodiment. As seen in FIG. 2 , sprockets SP7 and SP8 are coupled to sprocket mounting portion 14E by additional fastening members 42 . The bicycle rear sprocket assembly 10 includes a plurality of spacers SC3 disposed between the sprockets SP7 and SP8 in the axial direction D2. The spacer SC3 includes a spacer hole SC3A. The additional fastening member 42 extends through the through hole SP7D, the through hole SP8D, the mounting hole 20E, and the spacer hole SC3A. The spacer SC3 may be integrally formed with the additional fastening member 44 as an integral one-piece member. As seen in Figure 11, sprocket SP9 includes internal splines SP9S. Internal splines SP9S include internal spline teeth SP9T configured to engage external spline teeth (not shown) of bicycle rear hub assembly H (FIG. 2). As seen in FIG. 2, in the state where the bicycle rear sprocket assembly 10 is mounted on the bicycle rear hub assembly H, the sprocket SP9 is held in the axial direction D2 between the central portion 21 of the sprocket bracket 12 and the rear of the bicycle. Between the locking member H1 of the hub assembly H. As seen in FIG. 12, sprocket SP10 includes internal splines SP10S. The internal splines SP10S include a plurality of internal spline teeth SP10T configured to engage with a plurality of external spline teeth (not shown) of the bicycle rear hub assembly H (FIG. 2). As seen in FIG. 2 , in the state where the bicycle rear sprocket assembly 10 is mounted on the bicycle rear hub assembly H, the sprocket SP10 is held between the central portion 21 of the sprocket bracket 12 and the rear of the bicycle in the axial direction D2. Between the locking member H1 of the hub assembly H. As seen in FIG. 24, the sprocket SP11 includes internal splines SP11S. The internal splines SP11S include a plurality of internal spline teeth SP11T configured to engage with external spline teeth (not shown) of the bicycle rear hub assembly H (FIG. 2). As seen in FIG. 2, in the state where the bicycle rear sprocket assembly 10 is mounted on the bicycle rear hub assembly H, the sprocket SP11 is held in the axial direction D2 between the center portion 21 of the sprocket bracket 12 and the rear of the bicycle. Between the locking member H1 of the hub assembly H. As seen in FIG. 25, sprocket SP12 includes a torque transfer profile SP12F. Torque transfer profile SP12F includes a plurality of external spline teeth SP12G configured to mesh with sprocket SP11 to transfer rotational force. As seen in FIG. 13 , the sprocket SP11 includes a torque transfer profile SP11F. Torque transfer profile SP11F includes a plurality of additional inner spline teeth SP11G configured to mesh with outer plurality of spline teeth SP12G of sprocket SP12 to transfer rotational force. As seen in FIG. 2, the first sprocket member SP8 is fixed to the second sprocket member SP7. The second sprocket member SP7 is fixed to the primary radially extending surface 16E of the primary sprocket mounting portion 14E among the plurality of sprocket mounting portions 14A to 14E. The second sprocket member SP7 is disposed between the first sprocket member SP8 and the primary radially extending surface 16E of the primary sprocket mounting portion 14E with respect to the rotation center axis A1 in the axial direction D2. The second sprocket member SP7 is fixed to the primary radially extending surface 16E of the primary sprocket mounting portion 14E by the first sprocket fastener 44 . The first sprocket member SP8 is fixed to the second sprocket member SP7 by the first sprocket fastener 44 . In this embodiment, the second sprocket member SP7 is fixed to the primary radially extending surface 16E of the primary sprocket mounting portion 14E by a plurality of first sprocket fasteners 44 ( FIG. 26 ). The first sprocket member SP8 is secured to the second sprocket member SP7 by a plurality of first sprocket fasteners 44 ( FIG. 26 ). However, the total number of first sprocket fasteners 44 is not limited to this embodiment. The first sprocket member SP8 may be fixed to the second sprocket member SP7 by another fastening structure such as adhesive or diffusion bonding instead of the first sprocket fastener 44 or in addition to the first sprocket fastener 44 . The second sprocket member SP7 may be fixed to the primary sprocket mounting portion 14E by another fastening structure such as adhesive or diffusion bonding instead of the first sprocket fastener 44 or in addition to the first sprocket fastener 44. A primary radially extending surface 16E. The second sprocket member SP7 is in contact with the primary radially extending surface 16E of the primary sprocket mounting portion 14E. The first sprocket member SP8 is spaced apart from the primary radially extending surface 16E of the primary sprocket mounting portion 14E in the axial direction D2. The second sprocket member SP7 radially faces the primary axially extending surface 18E of the primary sprocket mounting portion 14E. The second sprocket member SP7 may be in contact with the primary axially extending surface 18E of the primary sprocket mounting portion 14E. The third sprocket member SP6 is fixed to the secondary radially extending surface 16D of the secondary sprocket mounting portion 14D of the plurality of sprocket mounting portions 14A to 14E. The third sprocket member SP6 is secured to the secondary radially extending surface 16D of the secondary sprocket mounting portion 14D by a second sprocket fastener 42 different from the first sprocket fastener 44 . The second sprocket fastener 42 is a separate component from the first sprocket fastener 44 . The second sprocket fastener 42 is disposed radially outward of the first sprocket fastener 44 . In this embodiment, the third sprocket member SP6 is secured to the secondary radially extending surface 16D of the secondary sprocket mounting portion 14D by a plurality of second sprocket fasteners 42 . However, the total number of second sprocket fasteners 42 is not limited to this embodiment. The third sprocket member SP6 may be fixed to the secondary sprocket mounting portion 14D by another fastening structure such as adhesive or diffusion bonding instead of the second sprocket fastener 42 or in addition to the second sprocket fastener 42. The secondary radially extending surface 16D. In this embodiment, the sprocket SP6 is the third sprocket member. However, sprockets SP1, SP4, and SP5 may be third sprocket members. The second sprocket member SP7 is disposed between the first sprocket member SP8 and the third sprocket member SP6 in the axial direction D2. The third sprocket member SP6 is in contact with the secondary radially extending surface 16D of the secondary sprocket mounting portion 14D. The second sprocket member SP7 is spaced apart from the secondary radially extending surface 16D of the secondary sprocket mounting portion 14D in the axial direction D2. The third sprocket member SP6 radially faces the secondary axially extending surface 18D of the secondary sprocket mounting portion 14D. The third sprocket member SP6 may be in contact with the primary axially extending surface 18E of the primary sprocket mounting portion 14E. In the above embodiments, the first sprocket member SP8 is fixed to the second sprocket member SP7 by the first sprocket fastener 44, and the second sprocket member SP7 is fixed to the second sprocket member SP7 by the first sprocket fastener 44. A primary radially extending surface 16E of the primary sprocket mounting portion 14E. However, the fixing structure of the first sprocket member SP8 and the second sprocket member SP7 can be applied to the combination of the sprockets SP1 and SP4, the combination of the sprockets SP4 and SP5, the combination of the sprockets SP5 and SP6, and the combination of the sprockets SP6 and SP7. combination. Second Embodiment A bicycle rear sprocket assembly 210 according to a second embodiment will be described below with reference to FIGS. 26 to 28 . The bicycle rear sprocket assembly 210 has the same structure and/or configuration as the bicycle rear sprocket assembly 10 except for the sprocket carrier 12 . Therefore, elements with substantially the same functions as those in the first embodiment will be numbered the same here, and for the sake of brevity, will not be described and/or illustrated in detail here. As seen in FIG. 26 , the bicycle rear sprocket assembly 210 includes a plurality of sprockets SP and a sprocket bracket 212 . The second sprocket SP2 is coupled to at least one of the sprocket carrier 212 and one of the plurality of sprockets SP1-SP12 at at least one additional circumferential coupling point CP2. In this embodiment, the second sprocket SP2 is coupled to the sprocket carrier 212 at at least one additional circumferential coupling point CP2. The second sprocket SP2 is coupled to the sprocket carrier 212 at a plurality of additional circumferential coupling points CP2. The bicycle rear sprocket assembly 210 further includes at least one fastening member 34 . The second sprocket SP2 is coupled to the sprocket carrier 212 by at least one fastening member 34 at at least one additional circumferential coupling point CP2. In this embodiment, the bicycle rear sprocket assembly 210 further includes a plurality of fastening members 34 . The at least one additional circumferential coupling point CP2 includes a plurality of additional circumferential coupling points CP2. The second sprocket SP2 is coupled to the sprocket bracket 212 at a plurality of additional circumferential coupling points CP2 by a plurality of fastening members 34 . As seen in FIG. 27, the structure of the sprocket bracket 212 is substantially the same as that of the sprocket bracket 12 of the first embodiment. In this embodiment, the sprocket bracket 212 includes a plurality of additional sprocket mounting portions 250 . A pair of additional sprocket mounting portions 250 extend radially outward from the sprocket mounting arm 22 . In this embodiment, the total number of additional sprocket mounting portions 250 is twelve. However, the total number of additional sprocket mounting portions 250 is not limited to this embodiment. For example, the pair of additional sprocket mounting portions 250 may be one sprocket mounting portion or at least three sprocket mounting portions. The arrangement of the circumferential coupling point CP1 , the additional circumferential coupling point CP2 , the additional circumferential coupling point CP3 and the second circumferential coupling point CP4 in the first embodiment can be applied to this embodiment. As seen in FIG. 28 , the additional sprocket mounting portion 250 is disposed between the sprockets SP2 and SP3 in the axial direction D2. The extra through hole SP1E is omitted from the first sprocket SP1. The spacers SC1 and SC2 are omitted from the bicycle rear sprocket assembly 210 . The additional sprocket mounting portion 250 includes a mounting through hole 250A and an additional mounting through hole 250B. The fastening member 34 extends through the through hole SP2D and the mounting through hole 250A. The additional fastening member 36 extends through the additional through hole SP2E, the through hole SP3D and the additional mounting through hole 250B. Third Embodiment A bicycle rear sprocket assembly 310 according to a third embodiment will be described below with reference to FIGS. 29 to 30 . The bicycle rear sprocket assembly 310 has the same structure and/or configuration as that of the bicycle rear sprocket assembly 10 except for the fixed structure of the sprockets SP4 and SP5. Therefore, elements with substantially the same functions as those in the above-mentioned embodiments will be numbered the same here, and for the sake of brevity, will not be described and/or illustrated in detail here. As seen in FIG. 29, in the bicycle rear sprocket assembly 310, the fixing structure of the first sprocket member SP8 and the second sprocket member SP7 is applicable to the fourth sprocket member SP5 and the fifth sprocket member SP4. Specifically, the fourth sprocket member SP5 is fixed to the fifth sprocket member SP4. The fifth sprocket member SP4 is fixed to the third-stage radially extending surface 16C of the third-stage sprocket mounting portion 14C of the plurality of sprocket mounting portions 14A to 14E. The fifth sprocket member SP4 is secured to the third stage radially extending surface 16C of the third stage sprocket mounting portion 14C by the third sprocket fastener 40 . The fourth sprocket member SP5 is fixed to the fifth sprocket member SP4 by the third sprocket fastener 40 . The third sprocket fastener 40 is distinct from the first sprocket fastener 44 and the second sprocket fastener 42 . The third sprocket fastener 40 is a separate component from the first sprocket fastener 44 and the second sprocket fastener 42 . The third sprocket fastener 40 is disposed radially outside of the first sprocket fastener 44 and the second sprocket fastener 42 . In this embodiment, the fifth sprocket member SP4 is secured to the third stage radially extending surface 16C of the third stage sprocket mounting portion 14C by a plurality of third sprocket fasteners 40 ( FIG. 30 ). The fourth sprocket member SP5 is secured to the fifth sprocket member SP4 by a plurality of third sprocket fasteners 40 ( FIG. 30 ). However, the total number of third sprocket fasteners 40 is not limited to this embodiment. The fourth sprocket member SP5 may be fixed to the fifth sprocket member SP4 by another fastening structure such as adhesive or diffusion bonding instead of the third sprocket fastener 40 or in addition to the third sprocket fastener 40 . The fifth sprocket member SP4 may be fixed to the third-stage sprocket mounting portion 14C by another fastening structure such as adhesive or diffusion bonding instead of the third sprocket fastener 40 or in addition to the third sprocket fastener 40 The third radially extending surface 16C. The fifth sprocket member SP4 is in contact with the third-stage radially extending surface 16C of the third-stage sprocket mounting portion 14C. The fourth sprocket member SP5 is spaced apart from the third-stage radially extending surface 16C of the third-stage sprocket mounting portion 14C in the axial direction D2. Each of the fourth sprocket member SP5 and the fifth sprocket member SP4 radially faces the tertiary axially extending surface 18C of the tertiary sprocket mounting portion 14C. At least one of the fourth sprocket member SP5 and the fifth sprocket member SP4 may be in contact with the tertiary axially extending surface 18C of the tertiary sprocket mounting portion 14C. The bicycle rear sprocket assembly 310 includes a plurality of spacers SC4 disposed between the fourth sprocket member SP5 and the fifth sprocket member SP4 in the axial direction D2. The spacer SC4 includes a spacer hole SC4A. The third sprocket fastener 40 extends through the through hole SP4D, the through hole SP5D, the mounting hole 20C and the spacer hole SC4A. Spacer SC4 may be integrally formed with third sprocket fastener 40 as an integral one-piece member. The sixth sprocket member SP1 is fixed to the fourth-stage radially extending surface 16B of the fourth-stage sprocket mounting portion 14B of the plurality of sprocket mounting portions 14A to 14E instead of the sprocket SP4 of the first embodiment. The sixth sprocket member SP1 is fixed to the fourth-stage radially-extending surface 16B of the fourth-stage sprocket mounting portion 14B by the fourth sprocket fastener 38 . The fourth sprocket fastener 38 is a separate component from the first sprocket fastener 44 , the second sprocket fastener 42 and the third sprocket fastener 40 . The fourth sprocket fastener 38 is disposed radially outward of the first sprocket fastener 44 , the second sprocket fastener 42 and the third sprocket fastener 40 . In this embodiment, the sixth sprocket member SP1 is secured to the fourth-stage radially-extending surface 16B of the fourth-stage sprocket mounting portion 14B by a plurality of fourth sprocket fasteners 38 ( FIG. 30 ). However, the total number of fourth sprocket fasteners 38 is not limited to this embodiment. The sixth sprocket member SP1 may be fixed to the fourth-stage sprocket mounting portion 14B by another fastening structure such as adhesive or diffusion bonding instead of the fourth sprocket fastener 38 or in addition to the fourth sprocket fastener 38. Four radially extending surfaces 16B. In this embodiment, the sprocket SP1 is the sixth sprocket member. However, sprockets SP2 and SP3 may be sixth sprocket members. The sixth sprocket member SP1 is in contact with the fourth-stage radially extending surface 16B of the fourth-stage sprocket mounting portion 14B. The sixth sprocket member SP1 radially faces the axially extending surface 18B of the fourth-stage sprocket mounting portion 14B. The sixth sprocket member SP1 can be in contact with the axially extending surface 18B of the fourth-stage sprocket mounting portion 14B. In this embodiment, as seen in FIG. 29, the sprocket SP2 is fixed to the radially extending surface 16A of the sprocket mounting portion 14A instead of the sprocket SP1 of the first embodiment. As seen in FIG. 30 , the sprocket S3 is fixed to the sprocket SP2 by a fastening member 34 . In addition, the second axial length AL2 is smaller than the first axial length AL1. The axial length AL4 of at least ten internal spline teeth ST is smaller than the axial non-spline length AL3. Modifications The structures of the bicycle rear sprocket assemblies 10 and 210 can be combined with each other. As seen in the bicycle rear sprocket assembly 310 of FIG. 31 , for example, the second sprocket SP2 is coupled to the sprocket carrier 212 and the plurality of sprockets SP1 to SP12 at at least one additional circumferential coupling point CP2 One or both. The second sprocket SP2 is coupled to both the sprocket bracket 212 and the first sprocket SP1 by a plurality of fastening members 34 at a plurality of additional circumferential coupling points CP2. As used herein, the term "comprises" and its derivatives are intended to specify the presence of stated features, elements, components, groups, integers and/or steps but not to exclude other unstated features, elements, components, groups, An open term for the presence of integers and/or steps. This concept also applies to words of similar meaning, such as the terms "having", "including" and their derivatives. The terms "member", "section", "portion", "part", "element", "body" and "structure" when used in the singular can have the dual meaning of a single part or a plurality of parts. Ordinal numbers such as "first", "second", "primary" and "secondary" described in this application are identifiers only and do not have any other meaning, such as a specific order and the like. Furthermore, for example, the term "first element" does not imply the existence of a "second element" by itself, and the term "second element" does not imply the existence of a "first element" by itself. The term "pair" as used herein may encompass configurations in which paired elements have different shapes or structures from each other, in addition to configurations in which paired elements have the same shape or structure as each other. Accordingly, the terms "a", "one or more" and "at least one" are used interchangeably herein. Finally, terms of degree such as "substantially", "about" and "approximately" as used herein mean a reasonable amount of deviation of the modified term such that the end result is not significantly changed. All numerical values described in this application can be understood to include terms such as "substantially", "about" and "approximately". Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is therefore to be understood that within the scope of the appended claims, the invention may be practiced otherwise than as specifically described herein.

10:自行車後鏈輪總成 12:鏈輪托架 14A:鏈輪安裝部分 14B:四級鏈輪安裝部分 14C:三級鏈輪安裝部分 14D:二級鏈輪安裝部分 14E:一級鏈輪安裝部分 16:徑向延伸表面 16A:第一徑向延伸表面 16B:第二徑向延伸表面/四級徑向延伸表面 16C:三級徑向延伸表面 16D:二級徑向延伸表面 16E:一級徑向延伸表面 18:軸向延伸表面 18A:第一軸向延伸表面 18B:第二軸向延伸表面/四級軸向延伸表面 18C:三級軸向延伸表面 18D:二級軸向延伸表面 18E:一級軸向延伸表面 19A:第一圓周鏈輪安裝部分 19B:第二圓周鏈輪安裝部分 20A:安裝孔 20B:安裝孔 20C:安裝孔 20D:安裝孔 20E:安裝孔 21:中心部分 22:鏈輪安裝臂 24:輪轂嚙合輪廓 26:第一輪轂內部花鍵 28:第一內部花鍵齒 30:第二輪轂內部花鍵 31:第二內部花鍵齒 32:緊固構件/第一緊固件 34:緊固構件/緊固件 36:額外緊固構件/額外緊固件 38:額外緊固構件/第二緊固件/第四鏈輪緊固件 40:額外緊固構件/第三鏈輪緊固件 42:額外緊固構件/第二鏈輪緊固件 44:額外緊固構件/第一鏈輪緊固件 210:自行車後鏈輪總成 212:鏈輪托架 250:額外鏈輪安裝部分 250A:安裝通孔 250B:額外安裝通孔 310:自行車後鏈輪總成 A1:旋轉中心軸線 AG21:第一內部花鍵表面角 AG22:第二內部花鍵表面角 AL1:第一軸向長度 AL2:第二軸向長度 AL3:軸向非花鍵長度 AL4:軸向長度 C:自行車鏈 CL2:參考線 CP1:第一圓周耦接點 CP2:額外圓周耦接點/第三圓周耦接點 CP3:額外圓周耦接點 CP4:第二圓周耦接點 D1:圓周方向 D2:軸向方向 D11:傳動旋轉方向 D12:反向旋轉方向 F1:傳動旋轉力 F3:推力 H:自行車後輪轂總成 H1:鎖定構件 H2:鏈輪支撐主體 II-II:線 L21:第一徑向線 L22:第二徑向線 MD1:第六最大鏈輪直徑 MD4:第五最大鏈輪直徑 MD5:第四最大鏈輪直徑 MD6:第三最大鏈輪直徑 MD7:第二最大鏈輪直徑 MD8:第一最大鏈輪直徑 MW2:圓周最大寬度 NS:沿圓周延伸非花鍵部分 NS1:環形凹槽 P2:圓周中心點 PA21:第一內部周節角 PA22:第二內部周節角 RC1:齒根圓 RC2:齒根圓 RC3:齒根圓 RC4:齒根圓 RC5:齒根圓 RC6:齒根圓 RC7:齒根圓 RC8:齒根圓 RC9:齒根圓 RC10:齒根圓 RC11:齒根圓 RC12:齒根圓 RC22:內部花鍵齒根圓 RL21:徑向長度 RL22:額外徑向長度 SC1:間隔件 SC1A:間隔件孔 SC2:間隔件 SC2A:間隔件孔 SC3:間隔件 SC3A:間隔件孔 SC4:間隔件 SC4A:間隔件孔 SP:鏈輪 SP1:第一鏈輪/第一鏈輪車輪/第六鏈輪構件 SP1A:第六鏈輪主體 SP1B:第六鏈輪齒 SP1C:齒底 SP1D:通孔 SP1E:額外通孔 SP2:第二鏈輪/第三鏈輪車輪 SP2A:鏈輪主體 SP2B:鏈輪齒 SP2C:齒底 SP2D:通孔 SP2E:額外通孔 SP3:第三鏈輪/第四鏈輪車輪 SP3A:鏈輪主體 SP3B:鏈輪齒 SP3C:齒底 SP3D:通孔 SP4:第四鏈輪/第二鏈輪車輪/第五鏈輪構件 SP4A:第五鏈輪主體 SP4B:第五鏈輪齒 SP4C:齒底 SP4D:通孔 SP5:第五鏈輪/第四鏈輪構件 SP5A:第四鏈輪主體 SP5B:第四鏈輪齒 SP5C:齒底 SP5D:通孔 SP6:第六鏈輪/第三鏈輪構件 SP6A:第三鏈輪主體 SP6B:第三鏈輪齒 SP6C:齒底 SP6D:通孔 SP7:第七鏈輪/第二鏈輪構件 SP7A:第二鏈輪主體 SP7B:第二鏈輪齒 SP7C:齒底 SP7D:通孔 SP8:第八鏈輪/第一鏈輪構件 SP8A:第一鏈輪主體 SP8B:第一鏈輪齒 SP8C:齒底 SP8D:通孔 SP9:第九鏈輪 SP9A:鏈輪主體 SP9B:鏈輪齒 SP9C:齒底 SP9S:內部花鍵 SP9T:內部花鍵齒 SP10:第十鏈輪 SP10A:鏈輪主體 SP10B:鏈輪齒 SP10C:齒底 SP10S:內部花鍵 SP10T:內部花鍵齒 SP11:第十一鏈輪 SP11A:鏈輪主體 SP11B:鏈輪齒 SP11C:齒底 SP11F:扭矩傳遞輪廓 SP11G:額外內部花鍵齒 SP11S:內部花鍵 SP11T:內部花鍵齒 SP12:第十二鏈輪 SP12A:鏈輪主體 SP12B:鏈輪齒 SP12C:齒底 SP12F:扭矩傳遞輪廓 SP12G:外部花鍵齒 ST:內部花鍵齒 ST1:內部花鍵傳動表面 ST1A:徑向最外邊緣 ST1B:徑向最內邊緣 ST2:內部花鍵非傳動表面 ST2A:徑向最外邊緣 ST2B:徑向最內邊緣 ST3:徑向最內端 TD1:第一最大齒底直徑 TD2:第三最大齒底直徑/額外最大齒底直徑 TD3:額外最大齒底直徑 TD4:第二最大齒底直徑 TD5:第五最大齒底直徑 TD6:第三最大鏈輪直徑 TD7:最大齒底直徑 TD8:最大齒底直徑 TD9:最大齒底直徑 TD10:最大齒底直徑 TD11:最大齒底直徑 TD12:第十二最大齒底直徑 XXIII-XXIII:線 XXIV-XXIV:線 XXIX-XXIX:線 10:Bicycle rear sprocket assembly 12: Sprocket bracket 14A: sprocket installation part 14B: Four-stage sprocket installation part 14C: Three-stage sprocket installation part 14D: Secondary sprocket installation part 14E: Mounting part of primary sprocket 16: Radially extending surface 16A: first radially extending surface 16B: Second Radial Extended Surface/Fourth Radial Extended Surface 16C: Tertiary Radially Extended Surface 16D: Secondary radially extending surface 16E: Primary radially extending surface 18: Axial extension surface 18A: first axially extending surface 18B: Second axially extending surface/fourth axially extending surface 18C: Tertiary axially extended surface 18D: Secondary axially extending surface 18E: Primary axial extension surface 19A: Mounting part of the first circumferential sprocket 19B: Mounting part of the second circumferential sprocket 20A: Mounting hole 20B: Mounting hole 20C: Mounting hole 20D: Mounting hole 20E: Mounting hole 21: Center part 22: Sprocket mounting arm 24: Hub engagement profile 26: Internal spline of the first hub 28: The first internal spline tooth 30: Internal spline of the second hub 31: Second internal spline teeth 32: fastening member/first fastener 34: fastening member/fastener 36: Additional Fastening Members/Additional Fasteners 38: Additional Fastening Member/Second Fastener/Fourth Sprocket Fastener 40: Additional Fastening Member/Third Sprocket Fastener 42: Additional Fastening Member/Second Sprocket Fastener 44: Additional Fastening Member/First Sprocket Fastener 210: Bicycle rear sprocket assembly 212: sprocket bracket 250: Extra sprocket installation part 250A: Mounting through holes 250B: Additional mounting through holes 310:Bicycle rear sprocket assembly A1: Rotation center axis AG21: First internal spline surface angle AG22: Second internal spline surface angle AL1: first axial length AL2: second axial length AL3: Axial non-spline length AL4: axial length C: bicycle chain CL2: Reference line CP1: first circular coupling point CP2: Additional Circumferential Coupling Point/Third Circumferential Coupling Point CP3: Extra Circumferential Coupling Point CP4: second circular coupling point D1: Circumferential direction D2: axial direction D11: Transmission rotation direction D12: reverse direction of rotation F1: transmission rotational force F3: Thrust H: Bicycle rear hub assembly H1: Lock member H2: Sprocket support body II-II: Line L21: first radial line L22: second radial line MD1: Sixth largest sprocket diameter MD4: fifth largest sprocket diameter MD5: Fourth largest sprocket diameter MD6: Third largest sprocket diameter MD7: second largest sprocket diameter MD8: The first largest sprocket diameter MW2: the maximum width of the circumference NS: Extend the non-splined part along the circumference NS1: Annular groove P2: circle center point PA21: First internal pitch angle PA22: second internal pitch angle RC1: root circle RC2: root circle RC3: root circle RC4: root circle RC5: root circle RC6: Root circle RC7: root circle RC8: root circle RC9: root circle RC10: Root circle RC11: Root circle RC12: Root circle RC22: Internal spline root circle RL21: radial length RL22: Extra radial length SC1: spacer SC1A: Spacer hole SC2: spacer SC2A: Spacer hole SC3: spacer SC3A: Spacer hole SC4: spacer SC4A: Spacer holes SP: Sprocket SP1: 1st sprocket/1st sprocket wheel/6th sprocket member SP1A: Sixth sprocket body SP1B: Sixth sprocket SP1C: tooth bottom SP1D: Through hole SP1E: Extra Via SP2: 2nd sprocket/3rd sprocket wheel SP2A: Sprocket body SP2B: sprocket teeth SP2C: tooth bottom SP2D: Through hole SP2E: Extra Via SP3: 3rd sprocket/4th sprocket wheel SP3A: Sprocket body SP3B: sprocket teeth SP3C: tooth bottom SP3D: Through hole SP4: 4th sprocket/2nd sprocket wheel/5th sprocket member SP4A: Fifth sprocket body SP4B: fifth sprocket SP4C: tooth bottom SP4D: Through hole SP5: Fifth sprocket/fourth sprocket member SP5A: Fourth sprocket main body SP5B: Fourth sprocket SP5C: tooth bottom SP5D: Through hole SP6: Sixth sprocket/third sprocket member SP6A: Third sprocket body SP6B: Third sprocket SP6C: tooth bottom SP6D: Through hole SP7: Seventh sprocket/second sprocket member SP7A: Second sprocket body SP7B: Second sprocket SP7C: tooth bottom SP7D: Through hole SP8: Eighth sprocket/first sprocket member SP8A: 1st sprocket main body SP8B: 1st sprocket SP8C: tooth bottom SP8D: Through hole SP9: ninth sprocket SP9A: Sprocket body SP9B: sprocket teeth SP9C: tooth bottom SP9S: Internal spline SP9T: Internal spline teeth SP10: tenth sprocket SP10A: Sprocket body SP10B: sprocket teeth SP10C: tooth bottom SP10S: Internal spline SP10T: Internal spline teeth SP11: Eleventh sprocket SP11A: Sprocket body SP11B: sprocket teeth SP11C: tooth bottom SP11F: Torque transfer profile SP11G: Additional internal spline teeth SP11S: Internal spline SP11T: Internal spline teeth SP12: Twelfth sprocket SP12A: Sprocket body SP12B: sprocket teeth SP12C: tooth bottom SP12F: Torque transfer profile SP12G: External spline teeth ST: Internal spline teeth ST1: Internal splined drive surface ST1A: Radial outermost edge ST1B: Radial innermost edge ST2: Internally splined non-drive surface ST2A: Radial outermost edge ST2B: Radial innermost edge ST3: Radial innermost end TD1: The first largest tooth bottom diameter TD2: third largest tooth bottom diameter/additional maximum tooth bottom diameter TD3: Additional maximum tooth bottom diameter TD4: The second largest tooth bottom diameter TD5: Fifth largest tooth bottom diameter TD6: Third largest sprocket diameter TD7: Maximum tooth bottom diameter TD8: Maximum tooth bottom diameter TD9: Maximum tooth bottom diameter TD10: Maximum tooth bottom diameter TD11: Maximum tooth bottom diameter TD12: Twelfth largest tooth bottom diameter XXIII-XXIII: Line XXIV-XXIV: Lines XXIX-XXIX: line

當結合附圖考慮時，參考以下詳細描述，本發明之更完整評價及其許多伴隨優點將易於獲得，同樣變得更好理解，其中： 圖1為根據第一實施例之自行車後鏈輪總成的側視圖。 圖2為沿圖1之線II-II截取之自行車後鏈輪總成的橫截面圖。 圖3為圖1中所說明之自行車後鏈輪總成之鏈輪的側視圖。 圖4為圖1中所說明之自行車後鏈輪總成之鏈輪的側視圖。 圖5為圖1中所說明之自行車後鏈輪總成之鏈輪的側視圖。 圖6為圖1中所說明之自行車後鏈輪總成之鏈輪的側視圖。 圖7為圖1中所說明之自行車後鏈輪總成之鏈輪的側視圖。 圖8為圖1中所說明之自行車後鏈輪總成之鏈輪的側視圖。 圖9為圖1中所說明之自行車後鏈輪總成之鏈輪的側視圖。 圖10為圖1中所說明之自行車後鏈輪總成之鏈輪的側視圖。 圖11為圖1中所說明之自行車後鏈輪總成之鏈輪的側視圖。 圖12為圖1中所說明之自行車後鏈輪總成之鏈輪的側視圖。 圖13為圖1中所說明之自行車後鏈輪總成之鏈輪的側視圖。 圖14為圖1中所說明之自行車後鏈輪總成之鏈輪的側視圖。 圖15為圖1中所說明之自行車後鏈輪總成的透視圖。 圖16為圖1中所說明之自行車後鏈輪總成之鏈輪托架的透視圖。 圖17為圖1中所說明之自行車後鏈輪總成之鏈輪托架的側視圖。 圖18為圖1中所說明之自行車後鏈輪總成之鏈輪托架的橫截面圖。 圖19為圖1中所說明之自行車後鏈輪總成之鏈輪托架的另一橫截面圖。 圖20為圖1中所說明之自行車後鏈輪總成之鏈輪托架的另一橫截面圖。 圖21為圖1中所說明之自行車後鏈輪總成之鏈輪托架的放大部分橫截面圖。 圖22為圖1中所說明之自行車後鏈輪總成的另一側視圖。 圖23為沿圖22之線XXIII-XXIII截取之自行車後鏈輪總成的橫截面圖。 圖24為圖13中所說明之鏈輪的另一側視圖。 圖25為圖14中所說明之鏈輪的另一側視圖。 圖26為根據第二實施例之自行車後鏈輪總成的側視圖。 圖27為圖26中所說明之自行車後鏈輪總成的部分側視圖。 圖28為沿圖27之線XXIV-XXIV截取之自行車後鏈輪總成的橫截面圖。 圖29為沿圖30之線XXIX-XXIX截取的根據第三實施例之自行車後鏈輪總成的橫截面圖。 圖30為圖29中所說明之自行車後鏈輪總成的側視圖。 圖31為根據修改之自行車後鏈輪總成的橫截面圖。 A more complete appreciation of the invention, and its many attendant advantages, will be readily obtained, and likewise better understood, by reference to the following detailed description when considered in conjunction with the accompanying drawings, in which: Fig. 1 is a side view of a bicycle rear sprocket assembly according to a first embodiment. Fig. 2 is a cross-sectional view of the bicycle rear sprocket assembly taken along line II-II of Fig. 1 . FIG. 3 is a side view of a sprocket of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. FIG. 4 is a side view of a sprocket of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. FIG. 5 is a side view of a sprocket of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. FIG. 6 is a side view of a sprocket of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. FIG. 7 is a side view of a sprocket of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. FIG. 8 is a side view of a sprocket of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. FIG. 9 is a side view of a sprocket of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. FIG. 10 is a side view of a sprocket of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. FIG. 11 is a side view of a sprocket of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. FIG. 12 is a side view of a sprocket of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. FIG. 13 is a side view of a sprocket of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. 14 is a side view of a sprocket of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. FIG. 15 is a perspective view of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. 16 is a perspective view of a sprocket carrier of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. 17 is a side view of the sprocket carrier of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. 18 is a cross-sectional view of the sprocket carrier of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. 19 is another cross-sectional view of the sprocket carrier of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. 20 is another cross-sectional view of the sprocket carrier of the bicycle rear sprocket assembly illustrated in FIG. 1 . 21 is an enlarged partial cross-sectional view of the sprocket bracket of the bicycle rear sprocket assembly illustrated in FIG. 1. FIG. Figure 22 is another side view of the bicycle rear sprocket assembly illustrated in Figure 1 . 23 is a cross-sectional view of the bicycle rear sprocket assembly taken along line XXIII-XXIII of FIG. 22 . Figure 24 is another side view of the sprocket illustrated in Figure 13 . Figure 25 is another side view of the sprocket illustrated in Figure 14 . Fig. 26 is a side view of the bicycle rear sprocket assembly according to the second embodiment. FIG. 27 is a partial side view of the bicycle rear sprocket assembly illustrated in FIG. 26. FIG. FIG. 28 is a cross-sectional view of the bicycle rear sprocket assembly taken along line XXIV-XXIV of FIG. 27 . 29 is a cross-sectional view of the bicycle rear sprocket assembly according to the third embodiment, taken along line XXIX-XXIX of FIG. 30 . FIG. 30 is a side view of the bicycle rear sprocket assembly illustrated in FIG. 29. FIG. Fig. 31 is a cross-sectional view of a bicycle rear sprocket assembly according to a modification.

10:自行車後鏈輪總成 10:Bicycle rear sprocket assembly

32:緊固構件 32: fastening member

34:緊固構件/緊固件 34: fastening member/fastener

36:額外緊固構件/額外緊固件 36: Additional Fastening Members/Additional Fasteners

38:額外緊固構件/第二緊固件/第四鏈輪緊固件 38: Additional Fastening Member/Second Fastener/Fourth Sprocket Fastener

40:額外緊固構件/第三鏈輪緊固件 40: Additional Fastening Member/Third Sprocket Fastener

42:額外緊固構件/第二鏈輪緊固件 42: Additional Fastening Member/Second Sprocket Fastener

44:額外緊固構件/第一鏈輪緊固件 44: Additional Fastening Member/First Sprocket Fastener

212:鏈輪托架 212: sprocket bracket

A1:旋轉中心軸線 A1: Rotation center axis

CP1:第一圓周耦接點 CP1: first circular coupling point

CP2:額外圓周耦接點/第三圓周耦接點 CP2: Additional Circumferential Coupling Point/Third Circumferential Coupling Point

CP3:額外圓周耦接點 CP3: Extra Circumferential Coupling Point

CP4:第二圓周耦接點 CP4: second circular coupling point

D1:圓周方向 D1: Circumferential direction

D11:傳動旋轉方向 D11: Transmission rotation direction

D12:反向旋轉方向 D12: reverse direction of rotation

SP:鏈輪 SP: Sprocket

SP1:第一鏈輪/第一鏈輪車輪/第六鏈輪構件 SP1: 1st sprocket/1st sprocket wheel/6th sprocket member

SP2:第二鏈輪/第三鏈輪車輪 SP2: 2nd sprocket/3rd sprocket wheel

SP3:第三鏈輪/第四鏈輪車輪 SP3: 3rd sprocket/4th sprocket wheel

SP4:第四鏈輪/第二鏈輪車輪/第五鏈輪構件 SP4: 4th sprocket/2nd sprocket wheel/5th sprocket member

SP5:第五鏈輪/第四鏈輪構件 SP5: Fifth sprocket/fourth sprocket member

SP6:第六鏈輪/第三鏈輪構件 SP6: Sixth sprocket/third sprocket member

SP7:第七鏈輪/第二鏈輪構件 SP7: Seventh sprocket/second sprocket member

Claims (17)

一種自行車後鏈輪總成，其經構形以安裝至一自行車後輪轂總成之一鏈輪支撐主體，該自行車後鏈輪總成包含：複數個鏈輪；及一鏈輪托架，其經構形以支撐該複數個鏈輪中之至少一者，該鏈輪托架包括：複數個內部花鍵齒，其經構形以與該自行車後輪轂總成之該鏈輪支撐主體嚙合，該複數個內部花鍵齒在一軸向方向上相對於該自行車後鏈輪總成之一旋轉中心軸線延伸；一沿圓周延伸非花鍵部分，其在一徑向方向上相對於該旋轉中心軸線自該複數個內部花鍵齒凹入；及該複數個內部花鍵齒包含複數個內部花鍵傳動表面；該複數個內部花鍵傳動表面各者包含一徑向最外邊緣，一徑向最內邊緣，及一徑向長度，其係自該徑向最外邊緣至該徑向最內邊緣界定，且該等徑向長度之總和在11mm至14mm之範圍內。 A bicycle rear sprocket assembly configured to be mounted to a sprocket support body of a bicycle rear hub assembly, the bicycle rear sprocket assembly comprising: a plurality of sprockets; and a sprocket bracket, configured to support at least one of the plurality of sprockets, the sprocket carrier comprising: a plurality of internal spline teeth configured to engage the sprocket support body of the bicycle rear hub assembly, The plurality of internal spline teeth extend in an axial direction relative to a center axis of rotation of the bicycle rear sprocket assembly; a circumferentially extending non-spline portion extends in a radial direction relative to the center of rotation the axis is recessed from the plurality of internal spline teeth; and the plurality of internal spline teeth comprises a plurality of internal spline drive surfaces; each of the plurality of internal spline drive surfaces comprises a radially outermost edge, a radial an innermost edge, and a radial length defined from the radially outermost edge to the radially innermost edge, and the sum of the radial lengths is in the range of 11 mm to 14 mm. 如請求項1之自行車後鏈輪總成，其中該複數個內部花鍵齒中之至少兩個內部花鍵齒相對於該自行車後鏈輪總成之該旋轉中心軸線以一第一內部周節角沿圓周配置，且 該第一內部周節角在13度至17度之範圍內。 The bicycle rear sprocket assembly according to claim 1, wherein at least two of the plurality of internal spline teeth have a first internal pitch relative to the rotation center axis of the bicycle rear sprocket assembly The corners are arranged along the circumference, and The first inner circumferential pitch angle is in the range of 13 degrees to 17 degrees. 如請求項2之自行車後鏈輪總成，其中該第一內部周節角為15度。 The bicycle rear sprocket assembly according to claim 2, wherein the first internal pitch angle is 15 degrees. 如請求項2之自行車後鏈輪總成，其中該複數個內部花鍵齒中之至少其他兩個內部花鍵齒相對於該旋轉中心軸線以一第二內部周節角沿圓周配置，且該第二內部周節角不同於該第一內部周節角。 The bicycle rear sprocket assembly according to claim 2, wherein at least two other internal spline teeth of the plurality of internal spline teeth are circumferentially arranged at a second internal circumferential pitch angle relative to the rotation center axis, and the The second internal pitch angle is different from the first internal pitch angle. 如請求項4之自行車後鏈輪總成，其中該第二內部周節角在28度至32度之範圍內。 The bicycle rear sprocket assembly according to claim 4, wherein the second internal pitch angle is in the range of 28 degrees to 32 degrees. 如請求項5之自行車後鏈輪總成，其中該第二內部周節角為30度。 The bicycle rear sprocket assembly according to claim 5, wherein the second internal pitch angle is 30 degrees. 如請求項1之自行車後鏈輪總成，其中該複數個內部花鍵齒中之至少兩個內部花鍵齒相對於該自行車後鏈輪總成之該旋轉中心軸線以一第一內部周節角沿圓周配置，且該複數個內部花鍵齒中之至少其他兩個內部花鍵齒相對於該旋轉中心軸線以一第二內部周節角沿圓周配置，且該第二內部周節角不同於該第一內部周節角。 The bicycle rear sprocket assembly according to claim 1, wherein at least two of the plurality of internal spline teeth have a first internal pitch relative to the rotation center axis of the bicycle rear sprocket assembly Angles are arranged along the circumference, and at least two other internal spline teeth of the plurality of internal spline teeth are arranged along the circumference at a second internal pitch angle relative to the rotation center axis, and the second internal pitch angles are different at the first internal pitch angle. 如請求項7之自行車後鏈輪總成，其中該第一內部周節角為該第二內部周節角之一半。 The bicycle rear sprocket assembly according to claim 7, wherein the first internal pitch angle is half of the second internal pitch angle. 如請求項1之自行車後鏈輪總成，其中該沿圓周延伸非花鍵部分經安置以使得該複數個內部花鍵齒由該沿圓周延伸非花鍵部分在該軸向方向上劃分成複數個第一內部花鍵齒及複數個第二內部花鍵齒。 The bicycle rear sprocket assembly according to claim 1, wherein the circumferentially extending non-spline portion is arranged such that the plurality of internal spline teeth are divided into plural numbers in the axial direction by the circumferentially extending non-spline portion A first internal spline tooth and a plurality of second internal spline teeth. 如請求項1之自行車後鏈輪總成，其中該等徑向長度之該總和在12mm至13mm之範圍內。 The bicycle rear sprocket assembly according to claim 1, wherein the sum of the radial lengths is in the range of 12 mm to 13 mm. 如請求項9之自行車後鏈輪總成，其中該複數個第一內部花鍵齒具有在4mm至5mm之範圍內的一第一軸向長度。 The bicycle rear sprocket assembly as claimed in claim 9, wherein the plurality of first internal spline teeth have a first axial length in the range of 4mm to 5mm. 如請求項11之自行車後鏈輪總成，其中該複數個第二內部花鍵齒具有在4.5mm至5.5mm之範圍內的一第二軸向長度。 The bicycle rear sprocket assembly according to claim 11, wherein the plurality of second internal spline teeth have a second axial length in the range of 4.5 mm to 5.5 mm. 如請求項1之自行車後鏈輪總成，其中該沿圓周延伸非花鍵部分具有在該軸向方向上界定之一軸向非花鍵長度，且該軸向非花鍵長度在7mm至9mm之範圍內。 The bicycle rear sprocket assembly according to claim 1, wherein the circumferentially extending non-spline portion has an axial non-spline length defined in the axial direction, and the axial non-spline length is between 7mm and 9mm within the range. 如請求項1之自行車後鏈輪總成，其中該複數個內部花鍵齒之一軸向長度及該沿圓周延伸非花鍵部分之一軸向非花鍵長度的一總和在16mm至21mm之範圍內。 The bicycle rear sprocket assembly as claimed in claim 1, wherein the sum of an axial length of the plurality of internal spline teeth and an axial non-spline length of the circumferentially extending non-spline portion is between 16mm and 21mm within range. 如請求項1之自行車後鏈輪總成，其中該沿圓周延伸非花鍵部分在一圓周方向上完全延伸。 The bicycle rear sprocket assembly according to claim 1, wherein the circumferentially extending non-spline portion is fully extended in a circumferential direction. 如請求項1之自行車後鏈輪總成，其中該鏈輪托架由一非金屬材料製成。 The bicycle rear sprocket assembly according to claim 1, wherein the sprocket bracket is made of a non-metallic material. 如請求項1之自行車後鏈輪總成，其中該鏈輪托架由一纖維強化塑膠製成。 The bicycle rear sprocket assembly according to claim 1, wherein the sprocket bracket is made of a fiber reinforced plastic.
TW110130827A 2017-05-30 2018-05-11 Bicycle rear sprocket assembly TWI803944B (en)

Applications Claiming Priority (22)

Application Number Priority Date Filing Date Title
US15/608,924 2017-05-30
US15/608,915 US11059541B2 (en) 2017-05-30 2017-05-30 Bicycle hub assembly
US15/608,915 2017-05-30
US15/608,924 US11332213B2 (en) 2017-05-30 2017-05-30 Bicycle rear sprocket assembly and bicycle drive train
US15/673,346 US10377174B2 (en) 2017-08-09 2017-08-09 Bicycle hub assembly
US15/673,346 2017-08-09
US15/686,179 2017-08-25
US15/686,177 2017-08-25
US15/686,177 US11179967B2 (en) 2017-05-30 2017-08-25 Bicycle hub assembly
US15/686,179 US11220309B2 (en) 2017-05-30 2017-08-25 Bicycle rear sprocket assembly
US201715712388A 2017-09-22 2017-09-22
US201715712407A 2017-09-22 2017-09-22
US15/712,407 2017-09-22
US15/712,388 2017-09-22
US15/851,781 2017-12-22
US15/851,781 US10946931B2 (en) 2017-09-22 2017-12-22 Bicycle rear sprocket assembly and bicycle drive train
US15/851,785 2017-12-22
US15/851,785 US10752320B2 (en) 2017-09-22 2017-12-22 Bicycle rear hub assembly
US15/879,353 US10625820B2 (en) 2018-01-24 2018-01-24 Bicycle rear sprocket assembly
US15/879,353 2018-01-24
US15/964,078 2018-04-27
US15/964,078 US10889353B2 (en) 2018-01-24 2018-04-27 Bicycle rear sprocket assembly

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