Shimano SM-BBR60 Ultegra/105 Bottom Bracket, Italian Threaded Cups
With reliable Shimano bearings and seals, the Shimano SM-BBR60 Ultegra/105 Bottom Bracket has a long service life.
HollowTech II integrated bottom bracket uses a wider bearing placement and larger axle diameter for increased stiffness and efficiency.
The bottom bracket is only compatible with frames that have an Italian standard bottom bracket shell (M36x24TPI). With an Italian threaded shell both sides of the shell are regularly right threaded, use a 36mm diameter and a 24tpi pitch thread. This differs to the British standard where one side of the shell is reverse threaded and the cups are smaller in diameter (1.37"). The width of an Italian bottom bracket shell is also wider measuring at 70mm compared to 68mm for a British road threaded bottom bracket.