Bottom Brackets and Bearings

❓1. What are the main types of bottom brackets?

There are two main families:

• Threaded (BSA, ITA) : the case screws into the frame. It is the most reliable, easy to maintain and quiet.
• Press-fit (BB86, BB92, PF30, BB30, etc.) : the cups are pressed into the frame. Lighter but sometimes a source of cracking if poorly assembled.

❓ 2. How do I know which case is compatible with my frame and crankset?

Three measures are essential:

The frame standard (BSA, BB86, PF30…).

The width of the case (68 / 70 / 73 mm, etc.).

The diameter of the bottom bracket axle (24mm Shimano, 30mm, DUB 28.99mm…).👉 The housing must match at once to the frame and to the pedal axle.

❓ 3. What criteria should you prioritize when choosing a quality case?

• Bearings : choose sealed and durable bearings (high-end steel or ceramic depending on budget).
• Waterproofing : essential if you ride in the rain or on gravel/MTB.
• Rigidity : influences power transmission.
• Ease of maintenance : some models allow you to change only the bearings.

If you want to know more, discover our advice guide:

How to choose your bottom bracket MTB