The Shimano Deore XT FC-M8100-1 crank features an entirely new construction, using direct mount chainrings, special gear tooth profile for improved chain retention, and a 172mm Q-factor. A high performance crankset from the classic MTB group Forged HollowTech II aluminium cranks offer unrivalled strength-to-weight ratio Lightweight construction for external super smooth bottom bracket bearings For use with 12-speed Dyna-Sys DCE single chainrings SM-CRM85 DCE chainrings are available in 28T, 30T, 32T, 34T and 36T 52 mm chain line for use with 142 / 148 mm rear axle width Stiffness and strength increased with advanced design due to wider spaced bearings and oversized axle 70 degree spider arm for optimal rigidity For use with 12-speed HG+ MTB chains only Chainring not included