The FC-R9100 Hollowtech II crankset’s shaping improves upon Dura Ace’s iconic 4-arm design, adding strength and rigidity while minimizing weight. Shimano’s Rider Tuned gearing offers a number of chainring configurations with a singular BCD for ease of use and versatility. Through redesigned chainring tooth profiling, the DURA-ACE R9100 crankset is adapted for the latest disc brake frame designs without the need to increase q-factor.