stripped bottom bracket
#1
Senior Member
Thread Starter
stripped bottom bracket
We have a cannondale furio in the shop with a stripped BB. I remember Mavic made a BB with a chamfered edge where you'd have to machine the shell to fit it, but it was a last ditch solution when threads stripped. Anything like that around today? Any other solutions to fixing stripped BB threads?
#2
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YST makes similar no-thread bottom brackets. It's not clear if chamfering the shell is needed. They are cheap and have a medicre reputation for durability. Here is one reference:
https://www.biketoolsetc.com/index.cg...=YS-BB99368110
Another approach is to ream the damaged English threads and retap the shell for Italian threads. You will need a 2 mm spacer to use an Italian bb but it will save theframe.
https://www.biketoolsetc.com/index.cg...=YS-BB99368110
Another approach is to ream the damaged English threads and retap the shell for Italian threads. You will need a 2 mm spacer to use an Italian bb but it will save theframe.
#3
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YST makes similar no-thread bottom brackets. It's not clear if chamfering the shell is needed. They are cheap and have a medicre reputation for durability. Here is one reference:
https://www.biketoolsetc.com/index.cg...=YS-BB99368110
Another approach is to ream the damaged English threads and retap the shell for Italian threads. You will need a 2 mm spacer to use an Italian bb but it will save theframe.
https://www.biketoolsetc.com/index.cg...=YS-BB99368110
Another approach is to ream the damaged English threads and retap the shell for Italian threads. You will need a 2 mm spacer to use an Italian bb but it will save theframe.
#4
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YST makes similar no-thread bottom brackets. It's not clear if chamfering the shell is needed. They are cheap and have a medicre reputation for durability. Here is one reference:
https://www.biketoolsetc.com/index.cg...=YS-BB99368110
Another approach is to ream the damaged English threads and retap the shell for Italian threads. You will need a 2 mm spacer to use an Italian bb but it will save theframe.
https://www.biketoolsetc.com/index.cg...=YS-BB99368110
Another approach is to ream the damaged English threads and retap the shell for Italian threads. You will need a 2 mm spacer to use an Italian bb but it will save theframe.
#6
Senior Member
Thread Starter
So where Italian is at 36mm v. ISO at 1.37, that .04 difference is enough for full depth of thread?
Cool. Cannondale did not want to talk to a non C'dale dealer about a warranty issue, so we pointed the customer toward the correct local shop. I'll offer up the Ital BB solution if he finds no love with C'dale warranty coverage.
Cool. Cannondale did not want to talk to a non C'dale dealer about a warranty issue, so we pointed the customer toward the correct local shop. I'll offer up the Ital BB solution if he finds no love with C'dale warranty coverage.
#7
Senior Member
You could drill and tap 8 holes in the circumference of the BB shell (4 on each side). Then, a sealed bottom bracket unit can be inserted and held in by 8 allen head screws.
I did a conversion like this on a Lambert (the old English bike with press fit sealed BB bearings?). Couldn't find replacement bearings and spindle, so had to adapt the frame to use something obtainable. It then allowed me to install a regular crankset, and I was able to get the bike together and rideable.
As this was done on a classic bike I wouldn't recommend it for every stripped BB job. I really wanted to get the Lambert running, and to prove to myself this kind of adaptation worked. It was a labor of love, took more time than it was probably worth. But it functioned just fine. And only an observant history buff would recognize the modification.
I did a conversion like this on a Lambert (the old English bike with press fit sealed BB bearings?). Couldn't find replacement bearings and spindle, so had to adapt the frame to use something obtainable. It then allowed me to install a regular crankset, and I was able to get the bike together and rideable.
As this was done on a classic bike I wouldn't recommend it for every stripped BB job. I really wanted to get the Lambert running, and to prove to myself this kind of adaptation worked. It was a labor of love, took more time than it was probably worth. But it functioned just fine. And only an observant history buff would recognize the modification.
#8
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