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Shimano XT RD-M8100 Rear Derailleur
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Shimano XT RD-M8100 Rear Derailleur


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Mfg PartNum: IRDM8100SGS
SALE: $113.04
MSRP: $118.99
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Next-Level 12 Speed MTB Drivetrain Silence

The Shimano Deore XT M8100 Series of derailleurs introduces a number of upgrades to optimize performance on 12 speed wide-range drivetrains.

With HYPERGLIDE+ the XT M8100 rear derailleur offers faster and shockless shifting over previous models

An innovative decreased chain/derailleur tension at the lowest gear and added bumper on the pulley cage decreases noice and cassette wear.

Combine all of this with a sleek low-profile designs and you've got a winning upgrade to any Shimano 12 speed drivetrain.


  • 284g claimed weight
  • Total capacity: 41 tooth
  • Low sprocket min/max: 51t
  • High sprocket min/max: 10t
  • 13t pulleys for increased efficiency

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.


Mfg PartNum: IRDM8100SGS 

Actuation: Mechanical 

Discipline: MTB 

Mount Type: Standard Rear Hanger 

Speed: 12 


Ordered by Most Relevant First
5 stars
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1 stars
Reviewed 6/19/2023
by Martin
Competitive Racer
Overall Rating
Excellent, bombproof, quick shifting. Just set it and forget it, it simply works.

XC, Endurance and Enduro

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