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General Repairs

How to Replace a Bike Bottom Bracket

Quick Answer

Remove the cranks, use a bottom bracket tool to remove the old unit, and install the new one with grease.

How to troubleshoot How to Replace a Bike Bottom Bracket

A worn bottom bracket causes creaking and rough pedalling. This guide covers removing and installing a new bottom bracket.

Step-by-Step Fix

  1. Remove the cranks using a crank puller tool.
  2. Use a bottom bracket tool to remove the old bottom bracket.
  3. Clean the threads in the frame.
  4. Apply grease to the threads of the new bottom bracket.
  5. Thread the new bottom bracket in by hand, then tighten with the tool.
  6. Install the cranks and torque to the correct specification.

Common Error Codes

CodeMeaningResolution
Creaking noiseBottom bracket loose or wornTighten or replace the bottom bracket.
Pedals feel roughBearings wornReplace the bottom bracket.

Frequently Asked Questions

How long does a bottom bracket last?

5000-10000 miles, depending on riding conditions.

Can I service a sealed bottom bracket?

No, sealed bottom brackets must be replaced.