The 12-speed Shimano XT M8100 crank profile is derived from the latest Shimano XTR chainset and uses a direct-mount chainring
Shimano’s latest drivetrain – of which these Shimano XT M8100 crank arms are literally central – represents the brand finally embracing the 1x revolution. The arms differ ever so slightly in shape from SLX, but if you squint, you’ll miss it. This revised shaping saves a few claimed grams (11g to be exact), and the surface finish also uses a more expensive process to better resist repeated scuffing and scrapes, which means it costs £30 more.
In common with SLX, XT’s 1x sprocket is held in place by an alloy lockring, and also uses an alloy ‘spider’ with a steel outer ‘toothed’ portion. The steel surface has a more expensive coating than SLX that should resist chain wear longer and, available in more sizes, it costs £25 more. Shimano’s latest tooth profile looks more like everyone else’s narrow/wide designs, but it now works fine with decent chain stability and no longer clogs or grinds excessively in UK winter mud.
One benefit of Shimano’s installation is no need for self-extraction bolts or crank pullers to remove, and the whole system connects together very precisely with zero play once you wind in a simple preload bolt on the axle and tighten two 5mm pinch bolts. Some riders argue these bolts look less clean than rival designs, but you simply can’t argue with the fit-and-forget functionality.
XT cranks are very stiff and direct from the first pedal stroke, and our experience is you simply don’t ever bend them, strip a thread or rip the pedal eyelet out, so durability is superb. The latest finish is better than previous generations, but it still scours off more quickly than we’d prefer. Being picky, XT isn’t that light for a premium level crank and you’ll need to spend a ton more cash to jump up to XTR if you want to shave grams and stay loyal to Shimano.