Bearings

Bicycle bearings for hubs, bottom brackets, headsets, suspension pivots and derailleur pulleys. Most modern bikes use sealed cartridge bearings identified by a code such as 6902 or 61803, which tells you the bore, outer diameter and width, so match that code exactly when replacing a worn bearing. Steel bearings are durable and easy to maintain, while ceramic hybrids trade a little longevity for lower friction.