The Shimano Ultegra 6800 bottom bracket has been reduced in size, and shaves 14g off of the 6700 version.
HollowTech II integrated bottom bracket uses a wider bearing placement and larger axle diameter for increased stiffness and efficiency
HollowTech II integrated bottom bracket seal design has minimal bearing interface ensuring smooth rolling and increased durability
Use TLFC37 or TLFC25 in conjunction with TLFC36 adaptor tool for installation and removal
Compatible with all Shimano Hollowtech II road cranks
New sealing system reduced drag by 50%