I'm getting weird noises coming from the bottom bracket (BB from now on), and I wanted to extract it to check if the problem is there or not.

The guide video I used is no longer public (free) as when I saw it the first time.

I've been successful extracting on another bike, but on this one, I have two issues:

  1. On the right side (drive side), made of metal, the extraction key doesn't fit! the key seems to be about 2mm wider than the circumference of the side, as seen on the picture below. I assume something distorted this side, this bike fell once, but I doubt this was damaged by that.

  2. The left side is made of plastic, and my hope was (because of the issue on the right side), to unscrew this side first, but it is very tight and I am fearful of it breaking if I apply more strength. By the way, the key fits perfectly on this side.

I've done this before on another BB and it came out just fine.

A picture to illustrate this: Bottom Bracket extraction problem

Finally the question(s):

Is there a different technique to extract this BB?

Is there hope in salvaging this BB? it may not be the part making the noise.

Any guess on why the right side is tighter?

  • I suspect you have the wrong tool. There are several different "standards" for cup tools. (Odd to have different sizes on the two sides, but the cartridge may have been replaced once without changing out the "fixed" cup.) Dec 7, 2011 at 12:55
  • More info on BB cartridge replacement from the Park Tool site: parktool.com/blog/repair-help/… Dec 7, 2011 at 13:00
  • @DanielRHicks nice link, thanks. What puzzles me is the different size on the right side, otherwise I think I would have been successful.
    – jackJoe
    Dec 7, 2011 at 15:31
  • 2
    (In my experience, "bottom bracket noise" is often due to the pedals.) Dec 7, 2011 at 17:27
  • 1
    @jackJoe -- Probably the left-side cup was stuck when the BB was replaced last, which is why they're different. And your noise could actually be due to having the wrong cup on the left side. Dec 7, 2011 at 23:03

1 Answer 1


I think you'll find that they are actually a different size. I'm struggling to find any information about it online but I can show you a picture of a tool that should deal with it. It's hard to say what the difference in size is but there is an obvious difference in thickness of the ends. You probably just need to find the other size tool and take out the metal end first.

Two sided bottom bracket tool One end of the tool The other end of the tool

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.