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Bottom BracketCompatibility Question(4 posts)

Bottom BracketCompatibility Questionawkchain
Nov 21, 2003 8:14 PM
Quick question - I'm thinking of transfering all of my '99 Chorus components to a late "80's steel frame. As far as I know it should be no problem, except I'm unsure if the b.b. is compatible. Weren't the axles much shorter then? How big a potential problem am I facing. Thanks in advance for advice.
re: Bottom BracketCompatibility Questionrussw19
Nov 21, 2003 9:38 PM
Actually the newer crank should have a shorter spindle. But the frame isn't the issue to the spindle length, just the cups. You need to make sure that the shell width and threading are the same if you want to transfer the BB. But the spindle length you match up to the crank.

If you need more info, let us know.

Russ
The only compatibility issue is whether...Tom C
Nov 21, 2003 9:42 PM
you've got a frame with an English or Italian BB. If your chorus BB is English and the older steel frame is Italian threaded all you would need is a contemorary Chorus BB i.e. 102mm length axle with Italian threaded cups. BB's are matched to cranks. Measure the width of your BB shell. If 68 millimeters edge to edge, the BB shell is English. If 70mm, it's Italian. You are right about BB spindles in the past being different but they were longer not shorter. On say, old Campy Record, 112 mm for the English double being an example. But that was to match to Campy Record and Super Record cranksets which were not dished as todays cranksets are. Just look at your Chorus BB, it should say whether it's Eng or Italian on the cups. then measure your shell as i suggested and you have all you need to know. Just make sure if you're installing an Italian BB to tighten it especially tight as they tend to unthread with use
Thanks for the help guys. nm awkchainawkchain
Nov 24, 2003 10:38 AM