# When To Replace a Bottom Bracket



## daniell (Apr 12, 2002)

It has been some time since I replaced my sealed cartridge bottom bracket. I do not want to do so needlessly however. When I spin the crank without the chain, it seems fine. Would it be better to remove the crank arms and spin the bottom bracket to make a determination?

Thanks


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## wim (Feb 28, 2005)

No point in removing the cranks. In fact, you need them to check for play. Make sure the cranks are tight on the axle, then grab the pedals (or crank ends) and try to rock the BB axle. If you feel play with a non-adjustable BB, time to replace it. Also, listen to the BB as it spins. Any grinding noises, start saving up for a new one.


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## looigi (Nov 24, 2010)

When you spin the crank without the chain on the rings, try turning it very very slowly. It should still be smooth. If it's notchy, it means the bearings are on the way out. That doesn't necessarily mean they need to be replaced right away though. Just keep checking them every so often and make a judgement as to what you think is bad enough to require replacement. As long as you don't opt for ceramic, BB bearings are pretty cheap (~$35) so if you have the tools, it's more a question of the work involved than the cost, IMO.


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## daniell (Apr 12, 2002)

Thanks a lot guys. Tried what was suggested. No play, No grinding noise.


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## Touch0Gray (May 29, 2003)

I replaced a ultegra because it was hard to turn, not notchy, not grinding, just not hard to turn...if anyone thinks it's still good it's all yours....pm me and I'll send it to you.

(I own no Shimano bikes anyhow)


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## joker (Jul 22, 2007)

I replaced the sealed bearing cartridge in my shimano xt bottom bracket , quite simple just chap out the old bearing race and press the new one in place , much cheaper than buying a new bottom bracket


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## burkeqc (Sep 25, 2006)

Sometimes a sealed BB will creak, which does not mean replacing it if other tests are met. Solution is to remove & regrease threads.


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## looigi (Nov 24, 2010)

burkeqc said:


> Sometimes a sealed BB will creak, which does not mean replacing it if other tests are met. Solution is to remove & regrease threads.


Creak can sometimes be caused by the shaft being dry where it passes through the inner races. Grease it.


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## Touch0Gray (May 29, 2003)

joker said:


> I replaced the sealed bearing cartridge in my shimano xt bottom bracket , quite simple just chap out the old bearing race and press the new one in place , much cheaper than buying a new bottom bracket


however, it doesn't convert a shimano octalink to a Campy ultra torque!


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## daniell (Apr 12, 2002)

joker said:


> I replaced the sealed bearing cartridge in my shimano xt bottom bracket , quite simple just chap out the old bearing race and press the new one in place , much cheaper than buying a new bottom bracket


Would that work with Ultegra bottom brackets?


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## carbonconvert (Apr 12, 2009)

Since its a cartridge bb, very obvious side play would be the only thing I would worry about. A little noise no big deal.Once it becomes annoying and rough when rotating, spend the 50 buck or whatever they cost. Otherwise, use it till it just don't work! Some parts are just throw-away items such as the b/b.


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## daniell (Apr 12, 2002)

Touch0Gray said:


> I replaced a ultegra because it was hard to turn, not notchy, not grinding, just not hard to turn...if anyone thinks it's still good it's all yours....pm me and I'll send it to you.
> 
> (I own no Shimano bikes anyhow)


Is it double or triple?


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## Touch0Gray (May 29, 2003)

double

edit: btw I tried (half heartedly I'll admit) to get it apart and almost ended up in the ER for stitches!

fwiw, I didn't hurt the bb


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## daniell (Apr 12, 2002)

Touch0Gray said:


> double
> 
> edit: btw I tried (half heartedly I'll admit) to get it apart and almost ended up in the ER for stitches!
> 
> fwiw, I didn't hurt the bb


Mine is a triple.

Thanks anyway

I did not know that they can be taken apart.


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## Touch0Gray (May 29, 2003)

everything CAN be taken apart.....whether it can be salvaged is another point entirely. I never did get it apart, I was sidetracked trying to staunch the bleeding


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## daniell (Apr 12, 2002)

Touch0Gray said:


> everything CAN be taken apart.....whether it can be salvaged is another point entirely. I never did get it apart, I was sidetracked trying to staunch the bleeding


Let me rephrase it. Many things are not designed to be taken apart.


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