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Shimano XT CS-M8100 12spd Cassette 12 spd 10-45T
12 spd 10-45T
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Shimano XT CS-M8100 12spd Cassette


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Mfg PartNum:
MSRP: $164.99
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SHIMANO DEORE XT - 12-Speed - HYPERGLIDE+ - MTB Cassette Sprocket

With its BEAM SPIDER construction, the new SHIMANO DEORE XT M8100 12-speed cassette shaves weight while increasing SHIMANO's MTB gearing range another gear. Using SHIMANO's new MICRO SPLINE freehub body and HYPERGLIDE+ tooth profile, these 10-45 and 10-51T cassettes deliver advanced shifting performance.


  • New shift ramp designs provide the fastest, smoothest shifts by HYPERGLIDE+
  • Lighter and stiffer construction
  • Reduces cassette inertia resulting in faster acceleration and increased chain security
  • 10T lowest sprocket realized by new FREEHUB body construction
  • Definitive shifting performance
  • Wide range and close step 12-speed drivetrain

  • 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.

    The product weight specified is an approximate weight based on the manufacturer's specifications (if available) or our measurement of one or two examples. For most products, the weight will typically vary by 5% to 10%.


    Cassette Use: MTB 

    Drivetrain Speed: 12-Speed 

    Cassette Type: Shimano 12 

    Mfg PartNum: CS-M8100-12 

    Series: SHIMANO DEORE XT M8100 Series 

    Weight: 461 g (10-45T), 470 g (10-51T) 

    Combination: 10-12-14-16-18-21-24-28-32-36-40-45T, 10-12-14-16-18-21-24-28-33-39-45-51T 

    Combination name: 10-45T, 10-51T 

    Compatible chain: HG 12-speed 

    Speeds: 12 

    Type: HYPERGLIDE (plus) 

    12 spd 10-45T

    Mfg PartNum: ICSM8100045 

    12 spd 10-51T

    Mfg PartNum: ICSM8100051 


    Ordered by Most Relevant First
    5 stars
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    1 stars
    Reviewed 12/21/2020
    by Alain L.
    Cycling Enthusiast
    Portland, OR
    Value Rating
    Overall Rating
    0 of 3 customers found this review helpful.
    High quality, lighter in weight

    I rarely find myself in a cog about 45t, so why add the weight. Besides, I like the teeth count jumps to be a little closer together. It's Shimano XT, do the quality is good. Knocked it down a star on "value" mostly because it's a lot of money for a cassette. I'm use to paying a lot less for all-road cassettes (ie, 12-27).

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