Dotek 170mm Alloy Chainset 42-32-22 This chainset is fitted as original equipment on a number of manufacturer cycles, it features alloy crank arms for minimal flex and hard wearing steel chainrings. Ideal as an upgrade over standard steel chainsets or as a replacement for worn or damaged parts. Compatible with shimano front indexing, with its profiled rings providing long term durability with smooth crisp gearshifts. We recommend bottom bracket with 118 for a good chain line.