Creaky bottom bracket

MTBNaomi.

I have had a creaky bottom bracket on my Specialized Rockhopper 08 disc for a while now, and from what I gather it's a fairly common occurance, but it's really loud and annoying, and I'm worried it might damage the frame...? It is only really loud when I stand on the pedals or pedal hard....

My BB is a (cpoied straight from the spec!!)
Shimano BB-ES25, Octalink spline, cartridge bearing, 68 x 118mm for 50mm chainline

I know there are loads of posts on the internet about creaky bottom brackets, but from what I've read I haven't found a definitive answer to my questions.....:

1. What causes it?
2. How can I fix it?
3. Is it possible to remove a cartridge BB to regrease?
4. Will it damage the frame if left like that for, say, another 50 miles?
5. Will I need a new BB? (please say no!!)

Thank you, and sorry for my rubbish bike knowledge!!

supersonic

Are you 100% sure it is the bottom bracket? Often is pedals, or the crank arms.

Park Tools has an excellent article on finding out what it is and curing it. Process of elimination.

To answer your last three questions, if it is the BB:

3) Yes, but only the threads. Could be that.

4) No

5) Probably not.

Does it spin smooth, no play?

nicklouse

is it the BB?

have a read of the Parktools creaky transmision topic. Link in the MTB FAQs
1 poor service/ lose bits.
2 tighten things.
3 sealed unite.
4 depends on what is the problem.
5 depends on what is the problem.

MTBNaomi.

Thanks v much, that's really useful!!

I am pretty convinced it's the BB, but my meagre bike knowledge is probably not enough to confirm this.... When I hold the pedals or cranks and feel for any sideways movement, there is none... And the crask is pretty loud, I really can't imagine it being just the pedals!!

Any ideas on what tools would be helpful.... I've looked at Shimano cartridge BB removers, what else is needed to remove and regrease, etc? Also, are all cartridge BBs sealed? Because I have read that sealed cartridge bbs can't be removed unless they are going to be replaced....

Thanks!

nicklouse

again have a read of Parltools all tools needed for any job are listed at the start of the topic.

there are other tools available than Park.

crank puller and shimano standard BB tool.