Author Topic: Removing BB From Eccentric Shell  (Read 449 times)

matteo77

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Removing BB From Eccentric Shell
« on: October 29, 2021, 06:04:55 AM »
Any tips on removing the bottom bracket from the eccentric bottom bracket shell? (Nomad MKII w/ Rohloff). Its stuck in there good. When I'm cranking on it with a breaker bar in the bike the set screws have gouged a little track on the shell and the bottom bracket itself hasn't budged. With the shell out of the bike it just spins in the vice.

I've tried plenty of penetrating oil, both sides, and made sure I'm turning in the correct direction. Ready to throw in the towel and buy a new eccentric shell unless anyone has some ideas?

Cheers!

WorldTourer

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Re: Removing BB From Eccentric Shell
« Reply #1 on: October 29, 2021, 06:52:00 AM »
You could take the shell to a LBS and ask them to put it in a vice, they may have some ideas. This is what I had to do.

Also, are you completely sure that you are unscrewing each side of the BB in the right direction?

geocycle

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Re: Removing BB From Eccentric Shell
« Reply #2 on: October 29, 2021, 09:28:28 AM »
Matteo, I had exactly the same experience.  I tried in the frame without success and gouged marks like you.  I also took it out and clamped it in a vice, again without budging it.  So I am afraid I moved on and bought a new EBB and BB.  I greased that up and have not had a problem with getting it in and out since.  Good luck!
 

mickeg

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Re: Removing BB From Eccentric Shell
« Reply #3 on: October 29, 2021, 12:31:27 PM »
If you have a hair dryer, warm the eccentric shell up with a hair dryer and then try it in the vice.  With heat it might be easier to unthread it and a hair dryer is not hot enough to damage anything.  If it was me, I would probably put it in the vice first, apply heat for several minutes.

When you put it in the vice, do not put the thin part of the eccentric at a vice jaw, that could deform and push the eccentric metal tighter on the threads, making it harder to unthread.

It might help if you add some penetrating oil either before or after you apply heat.  Do NOT use a spray can of something flammable if it is near an operating hair dryer, only use one at a time.

Try to loosen the left side first, not the right side.

That said, now that you have put grooves in the eccentric from the set screws, the eccentric might not work that well in the future if the set screws no longer work to hold it in place.  You might need a new one anyway.