Bottom bracket spacing - crankset hitting frame.

Gasket

Hello everyone.

I’ve just been working on my first bike build and have hit a snag.

The frame is a Ridgeback Solo World Single Speed. I have also bought a Stronglight 46T crankset which came with a barely-used 107x68mm Shimano bottom bracket - salvaged from a Specialized Langster.

I thought i’d try the bottom bracket in the frame and have found that when tightened up, the Stronglight crankset clashes with the chain stay on the frame.

I need to space the crankset some 2mm further away from the frame. Is this a case of fitting a different B.B. or is there a spacer or some sort.... or would I need to find a less ‘dished’ crankset?

Thank you very much.

cooldad

You need a longer BB.

Nick Payne

I assume you mean it's the chainring that hits the chainstay, not the crankarm. If so, you could fit a spacer under the drive side cup to move the chainring further out, but the better option is to fit a longer BB.

milemuncher1

113mm BB should do it.

imposter2.0

Stronglight track/SS cranks usually pair with either 103 or 107 JIS BBs (which is what you have) - so in principle you should not be having any issues with clearance. Can you post a pic of the problem?

Gasket

Hi folks - thank you for the help. Happy to order another B.B. if that’s what is needed?

It was tempting to file down the back of the crank - but it would need too much meat taken out of it.

So I’m guessing a 110mm bottom bearing would increase clearance by 3mm from the 107mm unit currently fitted? Just need to get it right for the mock-up before it’s dismantled for the respray.

Here are the pics requested:

imposter2.0

Bear in mind an extra 3mm will only give you 1.5mm each side...