Shimano Ultegra CS-R8100 12-Speed Cassette

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Enjoy faster, smoother shifting under maximum pedaling force with the Shimano Ultegra CS-R8100 12-Speed cassette. It lets you climb, sprint or cruise without thinking about your next gear change.


  • Larger driving cogs maximize drivetrain efficiency and are compatible with both Shimano 11- and 12-speed FREEHUB bodies
  • HYPERGLIDE+ revolutionizes off-road shifting with its seamless shifts up and down the gear range
  • Refined 12-step gear combination provides peak efficiency and accelerating performance for every racing situation
  • Faster, smoother shifts under maximum pedaling force
  • Cassette cogs: 11–30 T: 11-12-13-14-15-16-17-19-21-24-27-30; 11–34 T: 11-12-13-14-15-17-19-21-24-27-30-34


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Technical Specs

Best Use

Road Cycling



Compatible Freehub

Shimano Hyperglide (HG)


11-30 T: 291 grams

11-34 T: 345 grams

2 reviews with an average rating of 5.0 out of 5 stars

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