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Shimano XT FC-M8000-B1 Boost 1x Crank Arms

27% Off
sale from $109.95 $149.99

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    • Black, 170mm
      sale $119.99
    • Black, 175mm
      sale $109.95

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    More everything.

    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
    Recommended Use
    cross-country, downhill, enduro, trail
    Manufacturer Warranty
    2 years

    Tech Specs

    What do you think about this product?


    >Rating: 5


    Familiarity: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.

    >Rating: 4

    Nice upgrade

    Familiarity: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

    Familiarity:I've put it through the wringer

    Nice crank set at a great value.

    >Rating: 5

    Lightweight. Durable.

    Familiarity: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.

    >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.


    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.


    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?


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



    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.