I seem to have got myself all confused trying to understand compatibility between bb30 bb's, normal bb's and cranks. My road bike has a bog standard shimano external bearing bb. I want to upgrade the chainset to ultegra. I've seen one advertised, but its saying it comes with a bb30 bb. So the question is, will the chainset only work with the bb30 bb, or will it work with my older style bb?
Thanks in advance for untangling my brain.
Kevin
If you have an standard threaded BB (or one of those with external bearings) then you need an standard crank NOT BB 30. with BB30 the axle is massive (hence the stiffness beniefits) but it wont fit in a standard threaded shell - you need an oversized shell.
However if you have a BB30 frame - you can retrofit a standard crank with the right spacers or an insert in the shell (but why would you want to?)
I didn't think Shimano did BB30.
Shimano don't do BB30 chainsets, so an Ultegra chainset will fit your standard frame.
A proper BB30 chainset will have a 30mm axle and will not fit a standard frame.
So... although The Badger's advice is true, it sounds like whoever is selling the Ultegra chainset is confuddled!
:DThanks guys. That was the conclusion I thought I had come to, and having just had a look on shimano's website, it seems to confirm that they don't do bb30. Just the answer I wanted to hear 8)