Shimano Ultegra FC-R8000 52-36T 172.5mm

Optimized lightweight crank arm design produces excellent power transfer efficiency
HOLLOWTECH II
Redesigned FC for greater frame compatibility
Rider tuned gear performance through various gear combinations
Wider gear pitch increases clearance between chain and leading teeth to provide compatibility with frames with O.L.D. 135mm and 410mm chain stay length
Possible to choose the best choice for ride
46-36T, 50-34T, 52-36T, 53-39T
Minimized weight without sacrificing stiffness
165, 170, 172.5, 175mm