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Discussion Starter · #1 ·
When working on standard bikes, I recall we are told to remove the left side of the BB first, right side second. When reinstalling a sealed bearing BB, do we do right first, left second?

IIRC, we do this because the left side is used to secure the BB in the shell, so we want it to go back in AFTER we have tightened the right side to the proper torque, around 40 N-M. Am I correct, or do I have it backwards?

Thans in advance.
 

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correct..

Notice the the right side of most (not all) BBs has a lip that's larger in diameter than the threads so it bears against the right face of the BB shell. If the left side (which has no lip) was installed first, there would be nothing to indicate how far to screw the cup in and the right cup might never touch the BB face, if the left side was installed first.

http://www.parktool.com/repair/readhowto.asp?id=94
 

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felt huh? i'm guessin' this is shimano? cant say for sure, but when i built my campy, the DS (attached to the rest of the BB) went in first, then the empty NDS cap secured the whole thing. 50nm IIRC, but i did it by estimate... pretty simple with campag because the DS is lipped so it wont go further, the NDS isn't but you can tell when to stop there...

edit: ^^ damn, beat me to it :p
 

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Discussion Starter · #4 ·
Thanks guys for the help. That's exactly what I needed to know. Now IIRC, the last one I did had a lip, and now i realize what it was for. Perfect!
 
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