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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
Shimano Ultegra CS-R8100 12-Speed Cassette

Ultegra CS-R8100 12-Speed Cassette

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Backorder: This item is currently not in stock but is available to purchase today as a backorder. The expected availability date shown above is our best estimate as to when it will be shipped to you, but this date is subject to change based on our receipt of this item from its vendor. Shipping in the continental US is free for all backorder items (for international orders, our customer service team will contact you when the item is available to ship). Your credit card will not be charged until your item ships (Paypal requires payment up front, but you can cancel for full refund). Anytime prior to shipment, your backorder can be cancelled by contacting our customer service team.

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 Type: Shimano 12 


    Mfg PartNum: ICSR810012130 

    11/34 Tooth

    Mfg PartNum: ICSR810012134 

    Ordered by Most Relevant First
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    Works well
    by BB in AZ

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

    Reviewed 9/5/2022
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