1 Piece to 3 Piece Bottom Bracket Conversion Kit

American to European adapter kit for converting standard 1 piece crank bicycles to be used with 3 piece wide cranks such as those included with our 4G 4 stroke kits. Kit features new bearing race reducer and European bottom bracket set with a semi-sealed mechanism. Includes all bearings and necessary hardware.

What's the difference between American & European bottom brackets? American bottom brackets (BB) are sometimes called "regular". They are larger in diameter than European BBs and are not threaded. They require the bearing cups to be pressed into the frame. American BBs are used for 1 piece cranks. European BBs are smaller in diameter and are threaded to allow you to screw in the bearing cups. European BBS are used for 3 piece cranks. If your bike has an American BB and you want to use 3 piece cranks then purchase this American to European adapter to convert the bottom bracket to the smaller size needed for your new 3 piece cranks.