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Shimano Ultegra CS-R8100 12-Speed Cassette
Shimano Ultegra CS-R8100 12-Speed Cassette
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Shimano Ultegra CS-R8100 12-Speed Cassette 1
Shimano Ultegra CS-R8100 12-Speed Cassette 2

Shimano Ultegra CS-R8100 12-Speed Cassette


Pricing and Order Section

Mfg PartNum:
$111.99 set
MSRP: $111.99
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Meet the New Paradigm in Road Shifting

The uninterrupted shifting experience of the Ultegra R8100 12-speed cassette range lets you climb, sprint, or cruise without stopping to think about your next gear change. Larger driving cogs maximize drivetrain efficiency and create compatibility with both Shimano 11 and 12-speed freehub bodies.

Hyperglide+ cassettes already revolutionized off-road engagement with seamless shifts up and down the gear range, now that technology has come to road cycling. Even during maximal climbing or sprinting efforts, riders no longer need to let up for precise shifting. In any gear, Shimano Ultegra R8150 drivetrains maximize efficiency thanks to larger cogs and retain compatibility with existing Hyperglide freehub bodies. All this while increasing to 12-gears.

Experience the new paradigm in road shifting with Ultegra R8100.


  • Refined 12 step gear combination delivers peak efficiency
  • Faster, smoother shifts under maximum pedaling force
  • Compatible with new 12-speed and road 11-speed freehub body
  • 12 speed Hyperglide+ technology
  • Available in 11-30t and 11-34t options
  • Chain compatibility: Shimano HG 12-speed
  • Weight: 291g (11-30T) 345g (11-34T)

    • B-Stock - This product has one or more B-Stock units available. These units can be purchased at a discount (see option select). B-Stock units were returned from other customers and may have missing or damaged packaging materials. These units are otherwise as new. The full manufacturer warranty applies. Click Here for more information.


    Cassette Use: Road 

    Cassette Type: Shimano 12 

    Drivetrain Speed: 12-Speed 

    Gear Steps: 11-12-13-14-15-16-17-19-21-24-27-30T 

    Gear Steps: 11-12-13-14-15-17-19-21-24-27-30-34T 

    11/30 Tooth

    Mfg PartNum: ICSR810112130 

    11/34 Tooth

    Mfg PartNum: ICSR810112134 


    Ordered by Most Relevant First
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    1 stars
    Reviewed 9/5/2022
    by BB in AZ
    Overall Rating
    1 of 1 customers found this review helpful.
    Works well

    Easy to install and setup Di2. Half the price of Dura Ace cassette

    Was this review useful to you? Yes/No
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    Mechanic's Corner

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