Make your BMX cranks feel smooth again with a new bottom bracket.
Not sure what size bottom bracket (also known as BB) you need?
Refer to this size guide for help:
- Mid bottom bracket: The most common in BB size, used in almost all modern BMX bikes. Bearings press straight into a frame with BB diameter of 41mm.
- Spanish bottom bracket: Invented by Flybikes and found on some aftermarket frames sold around 2005 - 2013. Bearings press straight into a frame with BB diameter of 37mm
- USA bottom bracket: The bearings are housed in alloy cups, to suit a frame with a BB diameter of around 51mm (2 inches).
- Euro bottom bracket: Small bearings are housed in threaded alloy cups, which screw into a frame with thread in the BB. BB diameter is 35mm.
Your crank spindle diameter determines bearing size and the most common sizes for freestyle BMX is 19mm, 22mm and 24mm.