Shimano Ultegra FC-R8100 Hollowtech II Crankset

Item number: 84397
Ultegra FC-R8100 Hollowtech II Crankset - anthracite/172.5 mm 34-50
Ultegra FC-R8100 Hollowtech II Crankset - anthracite/172.5 mm 34-50
Ultegra FC-R8100 Hollowtech II Crankset - anthracite/172.5 mm 34-50
Ultegra FC-R8100 Hollowtech II Crankset - anthracite/172.5 mm 34-50
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  • Online since 1998
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The Ultegra FC-R8100 Crankset by Shimano - For highly efficient power transfer

The Shimano FC-R8100 crankset converts the power you put into your Ultegra 2x12-speed road bike groupset into propulsion with high efficiency. Thanks to the proven Hollowtech II design, it meets all your requirements for stiffness and stability. You also benefit from the precise and fast shifting processes you are used to from Shimano drives. The crank arms are hollow-formed, as is the large chainring, which is partly made of carbon, resulting in significant weight savings. Apart from the axle, all essential parts were made of lightweight metal. FC-R8100 has an asymmetrical 4-arm bolt circle diameter of 110 mm. It produces a chainline of 44.5 mm and has a Q-factor of 148 mm.


Application: Road
Compatibility: Shimano 2x12-speed
Chainring Mount: 110 mm pitch circle, 4-arm asymmetrical

Technical Information:

Series: Ultegra R8100
Crank Arm Material: Aluminium
Chainring Material: Aluminium / Carbon, Aluminium
Axle Material: steel
Gradation: 34-50, 36-52
Crank Arm Length: 160.0 mm, 165.0 mm, 170.0 mm, 172.5 mm, 175.0 mm
Chainline: 44.5 mm
Q-Factor: 148 mm
Axle Diameter: 24 mm
Compatible BSA Shell Width: 68 mm
Recommended Bottom Bracket: SM-BBR60 or SM-BB72-41B Press Fit Hollowtech II (not included)
Recommended Chain: CN-M8100


Shift/Brake Lever: ST-R8150, ST-R8170, ST-R8060, ST-R9250, ST-R9270, ST-R9160, ST-R9180
Front Derailleur: FD-R8150, FD-R9250
Bottom Bracket: BB-R9100, SM-BB9000, SM-BBR60, SM-BB6700, SM-BB5700, BB-RS500, SM-BB4600, SM-BB92-41B, SM-BB72-41B, SM-BB71-41B, BB-RS500-PB
Chain: CN-M8100, CN-M9100, CN-M7100, CN-M6100


- perfect balance between stiffness, stability, weight and rotational efficiency
- optimised power transfer
- fast, high-precision shifting at the front
- hollow crank arms (Hollowtech)
- hollow-formed large chainring made of aluminium-carbon composite (Hollowglide)
- anodised crank arms and chainrings
- aluminium chainring bolts


Hollowtech II
Shimano Hollowtech II is a crank bottom bracket system designed to achieve an ideal ratio of stiffness, weight and rotational efficiency. It is based on an integration of the bottom bracket and the right crank arm and works with a 24 mm axle or bearing diameter, which has proven to be optimal in terms of stability. In many cases, the bearing cups are on the outside so that the load is better distributed. High-quality precision seals ensure a long service life.

Manufacturer Numbers:

160.0 mm 34-50: I-FCR8100MX04
160.0 mm 36-52: I-FCR8100MX26
165.0 mm 34-50: I-FCR8100AX04
165.0 mm 36-52: I-FCR8100AX26
170.0 mm 34-50: I-FCR8100CX04
170.0 mm 36-52: I-FCR8100CX26
172.5 mm 34-50: I-FCR8100DX04
172.5 mm 36-52: I-FCR8100DX26
175.0 mm 34-50: I-FCR8100EX04
175.0 mm 36-52: I-FCR8100EX26


- 1 x Shimano Ultegra FC-R8100 crankset (34-50 or 36-52 tooth)
- 1 x Shimano crank bolt


  • anthracite/170.0 mm 34-50: 700 g
  • anthracite/170.0 mm 36-52: 711 g


  • anthracite/160.0 mm 34-50, sold-out
  • anthracite/160.0 mm 36-52, sold-out
  • anthracite/165.0 mm 34-50, in stock
  • anthracite/165.0 mm 36-52, sold-out
  • anthracite/170.0 mm 34-50, sold-out
  • anthracite/170.0 mm 36-52, in stock
  • anthracite/172.5 mm 34-50, ships on Dezember (2022)
  • anthracite/172.5 mm 36-52, ships in calendar week 33 (August)
  • anthracite/175.0 mm 34-50, in stock
  • anthracite/175.0 mm 36-52, in stock

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