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ShimanoXT FC-M8000-B1 Boost 1x Crank Arms

Sale $124.99 - $149.99

Item # SHI00AX

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  • Black, 170mm ($124.99)
  • Black, 175mm ($149.99)
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Item # SHI00AX

XT FC-M8000-B1 Boost 1x Crank Arms

Shimano has given its original mountain drivetrain a well-deserved upgrade, and we appreciate the way the brand continuously spreads the wealth throughout its offerings. Its savvy engineers also showed that they're ready to embrace Boost 148 rear axle spacing, aptly observing the benefits of the new standard and choosing to now offer the XT FC-M8000-B1 Boost 1x Crank Arms with a 3mm offset chainline for XT acolytes invested in the Boost revolution.

With reliable, lightweight aluminum construction, the XT M8000 Boost Crank Arms boast many of the same features seen in their pricier, lighter XTR counterpart. These include weight-shaving Hollowtech II cold-forged construction and a new one-by, 11-speed platform, giving those of us who haven't achieved sponsorship a way of upgrading without emptying our wallets. The XT Crank Arms also borrow Shimano's innovative Dynamic Chain Engagement (DCE) tooth profile from XTR, which features tall, stainless steel teeth that curve slightly at the ends for better chain retention.

  • 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)

Tech Specs
Arm Materialaluminum, stainless steel
Arm Length170mm, 175mm, 180mm
Bolt Circle Diameter96mm
BB TypeBB-MT800 / BB-MT800-PA
Recommended Usecross-country, downhill, enduro, trail
Manufacturer Warranty2 years

Actual Weight

Black, 170mm
Black, 175mm
Excludes chainring. Includes crank arm fixing bolt, and chainring bolts.

Actual weights are measured in-house by the Competitive Cyclist team.

Have questions? Chat with a Gearhead

What do you think about this product?



Will this fit on a 30t oval chainring

>Rating: 5


I've put it through the wringer

This is a reasonably priced reliable crank. XT is a workhorse groupset and will not let you down.


My bike is boosted. I'm replacing a Race Face Aeffect that has threads stripped out of the crank arm. Will this XT set fit in a RaceFace TypeX bottom bracket?

Hello Chris, Both the Aeffect crank and this Shimano crank feature a 24mm spindle so this will be a direct replacement without a need to replace your bottom bracket. Please feel free to reach out to us if you have any additional questions or need anything else.

>Rating: 4

Nice upgrade

I've used it several times

Just bought a boost bike with low end cranks? Get these beauties and you are on your way to total domination.

>Rating: 5

Great Crank

I've put it through the wringer

Nice crank set at a great value.


Is the spider on this crankset specific for 1x or does it also accept 1 or 2 rings like the non-boost version of the XT M8000 1x11sp crankset?

>Rating: 5

Lightweight. Durable.

I've put it through the wringer

Because that's what defines XT, right? This is a great choice for people who are prone to bashing cranks on rocks, but still want something that is good quality and will hold up to said beating.


What is the difference between the "boost" and standard version of this crank?


>Rating: 5

Black bike, black cranks!

These work perfectly for my custom SB6 build, and look really good with the matte black frame!

>Rating: 5

Boost cranks

Needed these for a newer boost frame. While they're not the cool metalic shiny finish of the XTR's, they still look pretty baller on a black bike.

>Rating: 5


Have you been boosted? I you have a boost frame then you need a boost compatible crank. This is shimano's offering. The difference is 3mm.


What's the bcd or do you have to use proprietary shimano chain rings?

Bolt Circle Diameter 96mm. There are many other brands offering chain rings with a 96 BCD.