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ShimanoXTR FC-M9020-B1 Boost 1xCrankArms

Sale 35% OffCurrent price:$274.98 Original price:$420.99

Item # SHI00EY

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  • Grey, 170mm ($274.98)
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Item # SHI00EY

XTR FC-M9020-B1 Boost 1xCrankArms

Shimano might have been fashionably late to the 1x party but they made sure that upon arrival, the components had all gone through extensive engineering and real world riding so they were completely dialed and ready to up the trail game of the modern mountain rider. Shimano's FC-M9020-B1 XTR trail Crank Arms take everything we loved about the original M9020 Trail crank and added 3mm to the chainline so it would play nice with boost spaced (aka 148 OLD hubs) bikes. The propriety 96mm spaced, 4-bolt spider is designed for Shimano chainrings which feature a special tooth profile for maximum chain retention no matter how tough the trails get.

Shimano strongly believes in using the right material for the right job and forgoes carbon fiber in crank arm construction and instead uses a 3D HollowTech II construction out of cold-forged aluminum for superior strength, durability, and light weight. The stainless steel teeth of the chainring designed for the single-ring Trail crank feature an alternating, semi-hook shape to aid in chain retention and the smoothness of the chain's engagement. Much like the arms, the rings too are hollow and add rigidity and shed weight. The trail crank's spider is the same found on all the M9000-series XTR cranksets, and so it can accommodate any M9000 single- or double-ring combination in the series.

The Shimano FC-M9020-B1 Trail 1x Crank Arms come in a beautifully high-polished grey that will complement any top-end build. Lengths of 170 and 175mm are offered. The Q-factor is 174mm. The arms do not include chainrings or bottom brackets. Any and all chainring combinations that are compatible with these crank arms are designed for use with Shimano's 11-speed Dyna-Sys mountain drivetrains. Keep you boost bike all XTR with the FC-M9020-B1 crank arms.

  • XTR precision now for Boost bikes
  • Chainline bumps out 3mm to pair with Boost rear spacing
  • Clean design favors form, function, and fashion
  • Shimano's superior engineering allows for durable materials without heft
  • Compatible with Shimano's 4-Arm mountain chainrings

Tech Specs
Arm Materialaluminum
Arm Length170, 175mm
Chainring Sizes30 - 36T
Bolt Circle Diameter96mm
Q Factor174mm
Compatible ComponentsShimano Dyna-Sys11
Recommended Usecross-country, trail
Manufacturer Warranty3 years

Actual Weight

Grey, 170mm

Claimed Weight

Claimed weights are provided by the vendor.

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

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What do you think about this product?


>Rating: 5

Match that XTR

I've used it once or twice and have initial impressions

A nice alternative to SRAM/Race Face carbon cranks. And if you’re running an XTR drivetrain, it’s nice to match the cranks. Make sure to get the boost arms for most boost bikes. The non-boost will work, but you need to add shims/spacers to clear the chainstays, and the non-drive clamp arm isn’t all the way pressed onto the spindle.


Does this Crankset have a longer Axel than the standard FC-9020? According to the Shimano documentation this version comes with a couple of spacers that push the arms out by +3 mm on either side. What I am curious about is if the Axel is increased by 6mm as well or if the 6mm of space is just take up by a 'gap' in the non drive side 'splines'. Thanks!

Yes it is definitely longer than the standard 9020-1. Installed on a Yeti SB6 (boost frame).