Bicycle Mechanics - BB is toast, how to size w/o removing?

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billh
05-22-06, 01:17 PM
My BB is toast because I can wiggle my cranks back and forth and it's not the cranks because I tried tightening them last night. I can still ride it but it needs to be replaced. Is there any way to order the correct size without taking out. Reason is that it will take 2 weeks to get the part from Nashbar/ Performance and I still need to ride it to work. I'd really like to avoid, taking out, measuring, re-install bad part, new part arrive, uninstall old part again, install new part.

This is a cyclocross bike, some knock off from Korea but I believe it is road geometry, same as a Specialized road bike. Takes regular newer Ultegra crankset. Can I assume it is some standard road size BB, what 68mm english thread?

OLDYELLR
05-22-06, 01:23 PM
Is it really toast, or only in need of adjustment? Does it make bad noises other than clicking on each strole when you stand?
Landgolier
05-22-06, 01:33 PM
This should be pretty easy if you have a crank puller, just take off the cranks and measure the overall spindle length, then measure each side to the center to verify that it's a symmetrical BB. You should also measure the shell, but 99% chance it's 68mm anyway.

Also, nashbar/performance have a crappy selection and not hugely cheap prices on BB's, I would just buy local for this one. If you take it to them they will measure it for you, which means they will be at least theoretically responsible if they sell you the wrong unit.

I'm assuming this is already a cartridge BB, as if the OP knows enough to be able to tell it's smoked he also knows it's not adjustable.