BB installation ...

Just a quick one before the shop gets to see it ...

I have a Giant Bowery frame, nearly new and a new Shimano BB. The threads look alright, and size should be right - 68 x 113 - but the drive-side won't screw on easily. It fits but stops turning after a couple of rotations.

I have, gingerly, tried using a wrench to help it on its way, but don't know how much force is OK to use, and how much force indicates that something is wrong. Don't wanna screw up the frame.

Anyone got any advice?

Cheers

Might need to chase and face the threads first, had the same problem on my Sparton... Got BC to do it for me in the end...

Be very sure its going on straight before reaching for the wrench!

Clean the threads and apply assembly lube or grease.

Should turn without much force.

Might need to chase and face the threads first

To clarify:

Threads are chased.

BB shell is faced.

The drive side normally doesn't screw in all the way - you will almost always have some thread showing. As long as it won't come loose, the BB is secure, and isn't too tight to prevent the spindle from moving freely then you should be fine.

Oh. And be sure that the threads are well greased of course.

Be very sure its going on straight before reaching for the wrench!

Clean the threads and apply assembly lube or grease.

Should turn without much force.

+1. Should screw in fine by hand if threads are clean and greased.

cool. or not so cool. it doesn't go in enough by hand, even cleaned and greased.

will take it to me LBS. It's worth mentioning - it's on Lee High Road, between Lee Green and Lewisham, and the two mechanics are old-school blokes who just fix bikes all day. they're a bit grumpy at first but they're friendly enough after a bit and they sort bikes out well, and cheap.