Drive Train

When to Replace a Bottom Bracket on a Road Bike

By: Alex Bristol

Last Update:

If you own a bike, you will need to check it frequently to confirm that all parts are working perfectly.  Creaks are among the most common problems experienced by bike riders. In case you have been experiencing some unpleasant sounds when cycling, you need to check the status of the bottom bracket. You should follow these steps.

  • Ensure that the cranks are secured tightly by trying to wiggle them from side to side as you hold the frame. You can use a long Allen key when tightening in case you find that they are lose.
  • Get rid of the pedals and grease them.
  • Confirm if the chain ringbolts are tight and greased.
  • Ensure the saddle post is greased and then tighten it into its position.

In case the creaks are still there, even after you have done all the above, then you may need to change the bottom bracket. You will need the flowing tools when removing.

  • Allen key
  • Torque wrench
  • adjustable wrench
  • Crank extractor
  • Grease
  • Rag

Steps to follow when removing the bottom bracket

  • Shift the bottom bracket towards the largest part of the chain ring. This ensures that your hands are safe in case they slip. Get rid of the crank by removing the 8 mm Allen bolt. After removing this bolt, you can carefully line up a crank extractor using threads. Ensure that you have fastened properly to prevent stripping the crank threads. Once you have confirmed that the crank extractor is secured tightly in place, turn the drive side in clockwise direction in such a way that the crank will be pushed from the taper. Repeat this process on the left side.
  • After you have removed the cranks, you can now remove the bottom bracket. Place the bottom bracket remover on the left side of your bottom bracket.
  • Disengage the bottom bracket in a counter clockwise direction. Do this carefully to avoid damaging the threads.
  • After you have removed the bottom bracket, you should clean the area where you have removed it. In most cases, the dirt in this area is usually the major cause of creaks. Use a degreaser to get rid of any oxide build-up. Use a toothbrush to remove any dirt.
  • In case you want to install a new bottom bracket, you need to ensure that you have picked the correct size that matches with your bike. In case you are stuck, you can consult a bike expert before you install. Remember to grease the threads.
  • Now you have the bottom bracket in place, ensure that the left side aligns correctly on the frame.
  • Tighten the left side in clockwise direction. You can do this using your fingers but you should leave about 1 cm of the thread.
  • Using a suitable bottom bracket removal tool, you can tighten the drive side firmly in anti clockwise direction. You should also do this on the left side but you should tighten in clockwise direction. A torque wrench will be the best tool to use when tightening.

1.How do I know when to replace my bottom bracket? – Post by Bicycles Stack Exchange