Shimano Deore XT CS-M8100 Cassette, 12-Speed 10-51T Micro Spline

MPN ICSM8100051 / UPC 192790443843 / Model CS-M8100 / New

A 510 percent gear range from one cassette. The 10-51T CS-M8100 is the reason modern mountain bikes stopped needing a front derailleur: a 10-tooth sprocket for speed, a 51-tooth bailout for the steepest climb on your worst day, and HYPERGLIDE+ ramps that let you shift under full power in both directions without the drivetrain complaining.

✓ Authentic Shimano·Ships from California·Free 30-day returns·Dispatched in 1 business day

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Will it fit your bike?

Shimano 12-speed, Micro Spline freehub required

This cassette needs a Shimano Micro Spline freehub body, the standard on most 12-speed mountain wheels. It will not fit a traditional HG splined freehub or an XD driver. Pair it with a Shimano 12-speed chain and a long-cage (SGS) 12-speed derailleur rated for 51T (XTR, XT, SLX or Deore M-series).

Not sure about your freehub? Message us with your wheel or hub model and we will confirm before you order.

What makes it special

10-51T, a 510 percent range. Wider than a full 2x drivetrain used to give you, from one shifter.
HYPERGLIDE+. Shift under full power, up or down the cassette, and the chain walks across on machined ramps instead of slamming.
Beam spider construction. The big sprockets sit on an aluminum carrier that keeps weight down without giving up stiffness.
E-bike rated. Built to take motor torque, so it holds up on an e-MTB as well as an analogue bike.
Deore XT durability. The workhorse groupset: XTR technology, everyday price, seasons of wear life.

The details

Brand	Shimano
Series	Deore XT M8100 (12-speed)
Model	CS-M8100
MPN	ICSM8100051
UPC	192790443843
Type	Cassette
Speeds	12-speed
Range	10-51T
Sprockets	10-12-14-16-18-21-24-28-33-39-45-51
Freehub	Shimano Micro Spline only
Shifting	HYPERGLIDE+
Material	Steel sprockets, aluminum beam spider
Weight	470 g (16.6 oz)
Color	Silver / Black
Country of manufacture	Japan
Condition	Brand new, original Shimano retail packaging

Delivery & returns

Ships from California with tracking, typically arriving in 3-5 business days, dispatched within 1 business day. Free 30-day returns, we cover return shipping.

Mizuki · Authentic Shimano · Ships from USA