Bicycle bracket bearings and washers

The bottom bracket is a component that connects the cranks (pedals) to the bicycle frame and allows them to rotate smoothly. It is located in the middle of the bicycle, in the so-called bottom bracket shell. Inside are bearings that allow the axle to run smoothly, on which the cranks are mounted.

What types of bottom bracket bearings are there?

There are several types of bearings used in bicycle bottom brackets, differing in design, installation, maintenance, and use. Here is an overview of the main types of bearings used in bottom brackets:

Loose ball bearings

Description: Individual balls located inside a central housing, often caged or free-running.
Advantages: Simple and inexpensive, allow preload adjustment.
Disadvantages: They require regular maintenance (cleaning, lubrication, adjustment), sensitive to dirt.
Use: Older or cheaper bicycles, classic threaded BSA/ITA bottom brackets.

Sealed cartridge bearings

Description: The entire bearing mechanism is enclosed in a cartridge, typically with a seal (2RS – on both sides).
Advantages: Maintenance-free, well protected against water and dirt, easy to replace.
Disadvantages: Cannot be serviced – the entire bearing must be replaced after wear.
Use: In modern bottom brackets such as Hollowtech II, DUB, PressFit, BB30, etc.

Hybrid ceramic bearings

Description: Bearings with ceramic balls (e.g. silicon nitride – Si₃N₄) and steel raceways.
Advantages: Low friction, higher hardness, lower weight, corrosion resistance.
Disadvantages: Higher price, can be more fragile, often unsuitable for poor conditions (mud, rain).
Use: Road and performance bikes, racing.

Full ceramic bearings

Description: Balls and raceways made of ceramic materials.
Advantages: Extremely low friction, very light and corrosion resistant.
Disadvantages: Extremely expensive, fragile – unsuitable for MTB or everyday use.
Use: Top-level road or time trial bikes only.

Needle / roller bearings

Description: Instead of balls, they contain rollers or needles.
Advantages: Larger contact area → higher load capacity.
Disadvantages: Less common in bicycle hubs, more complex sealing, higher friction.
Use: Some special models (e.g. Enduro MAX), rather exceptional.

Check out our video "Bike bearings - good to know"