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ShimanoXT FC-M8000-B1 Boost 1x Crank Arms

ShimanoXT FC-M8000-B1 Boost 1x Crank Arms


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5 out of 5 stars
7 Reviews

XT FC-M8000-B1 Boost 1x Crank Arms

Shimano’s famous for its commitment to trickle-down tech and, sure enough, there’s plenty top-shelf inspiration to be found in the XT FC-M8000-B1 Boost 1X Crank Arms. Obviously, they’re designed to play nicely with Boost 148 rear axles, with a 3mm offset chainline that keeps your links running smoothly between cassette and chainring. The more expensive XTR’s Hollowtech II construction has also trickled down to XT, letting you save weight and cash, and the new 1x11 platform lets you enjoy so much gear that you’ll practically be moving backwards on those steep climbs.


  • Crank arms for efficient power transfer on varied terrain
  • Cold-forged aluminum construction provides lightweight strength
  • Hollowtech II construction reduces weight and maintains rigidity
  • 11-speed compatibility improves gear-range possibilities
  • Asymmetrical design enhances strength strategically
  • Compatible with 3d Composite Chainrings (sold separately)
  • Item #SHI00AX

Tech Specs

Arm Material
aluminum, stainless steel
Arm Length
170mm, 175mm, 180mm
Bolt Circle Diameter
BB Type
BB-MT800 / BB-MT800-PA
Q Factor
Claimed Weight
[36T] 1lb 8.8oz (698g)
Manufacturer Warranty
2 years
mountain biking

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