Bottom Brackets Of All Types
The bottom bracket is part of the ‘engine room’ of your bike. It is the component that allows your crank arms and chainring to turn smoothly and will eventually need to be replaced, as all components on the bike will do. When it comes to replacing the bottom bracket there are several options to choose from, including different thread sizes, sizes and types. The best bottom bracket to choose is one that fits your frame well, if you are unsure it is often a good idea to speak to a bike mechanic about the best option.
Closed BB Systems
Most bottom brackets are closed systems as this helps to give the bracket more longevity as the bearings and inner working aren't exposed to as many elemental factors, such as rain. It is still possible to but open systems where you can re grease and replace the bearings individually, but these are much less common.