The advent of super-wide range 11spd cassettes on mountain bikes has made a single-chainring setup a real option for many riders. The SL-K Compact Single uses our 386 three-armed spider which delivers huge stiffness. The crankarms are unidirectional carbon fiber with an alloy spine inside to boost strength with a minimal weight penalty. Six chainring sizes are available, all CNC machined from high-strength 7075 aluminium. The rings are optimised for use with 11spd transmissions and are designed for maximum chain retention. Choose from BB30 or MegaExo versions, both with a forged 7075 spindle.