Bottom Brackets are the parts of the bike that fit through your frame and to which your chainset attaches. Using bearings they enable your cranks to turn and in doing so move the chain, thus propelling the bicycle. They are an essential part of the gear system. Available in several different sizes depending on the width of the bottom bracket shell in the frame, it is essential that the correct size is fitted; so be sure to contact us if in doubt.
Differing Bracket Styles
There are three different types of internal BB - Square Taper, Isis and Octalink; which refers to the interface, or the way the cranks fit to the BB. Manufacturers in recent years have also developed an external BB which is easier to fit and maintain. Shimano call this the Hollowtech system, although other manufacturers such as Raceface and FSA have compatible systems that are specific to certain cranks.