Bicycle Mechanics - bottom bracket problems,!~

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View Full Version : bottom bracket problems,!~

sebastian21
11-16-05, 07:15 PM
HI, im installing a new bottom bracket in a frame that im building but the issue is that the bottom goes all the way in if you look it from the top it goes all they way in but if you are looking it from the bottom the bottom bracket does not goes all they way in, there is like 1 cm out... Its ok to use it like that..??

Noam Zane
11-16-05, 07:26 PM
I've done three or four disections of your post and still can't figure out what it is you're asking.
sydney
11-16-05, 07:40 PM
I've done three or four disections of your post and still can't figure out what it is you're asking. +1 It couldn't even be cross threaded and be that crooked.

sebastian21
11-16-05, 07:48 PM
the BB cup is flush against the frame when viewed from the top, but that there's a one mm gap when viewed from the bottom?
Sluggo
11-16-05, 08:12 PM
Either the cup is cross threaded or the BB shell is not square. An English-thread cup in an Italian-thread BB would fit loosely enough that you would not need to force it and it could still cross-thread

Does the cup screw in easily but with enough solidity that it feels like it is engaging all the threads? If you have the right cup, you probably need to take it to a shop that has the tools to clean the threads and/or face the BB so it is square to the threads. Or if the threads are really messed up, the shop can ream out the old threads and tap to Italian.

What kind of frame is it?
HillRider
11-16-05, 08:13 PM
Well, 1 mm is way different from 1 cm! It sounds like the frame has to have the bottom bracket shell faced to square it up. Currently the faces arent exactly square to the center line so the bottom bracket stops before it meets the edge uniformly. Any well equipped bike shop can correct this for you.
sebastian21
11-16-05, 08:17 PM
ok, what im going to do is take it to the shop? thanks anyways
sydney
11-16-05, 08:24 PM
Either the cup is cross threaded or the BB shell is not square. An English-thread cup in an Italian-thread BB would fit loosely enough that you would not need to force it and it could still cross-thread

Does the cup screw in easily but with enough solidity that it feels like it is engaging all the threads? If you have the right cup, you probably need to take it to a shop that has the tools to clean the threads and/or face the BB so it is square to the threads. Or if the threads are really messed up, the shop can ream out the old threads and tap to Italian.

What kind of frame is it?Actually, it does not 'fit' at all and can't be crossthreaded because an english BB will drop right into an italian shell.The threading is also opposite directions on the drive side anyway.
sydney
11-16-05, 08:26 PM
ok, what im going to do is take it to the shop? thanks anywaysYou could have it faced,but if you are using a cartridge BB and the spidle does not bind up when the catrtridge is properly tightened, no real problem.
Sluggo
11-16-05, 08:29 PM
Actually, it does not 'fit' at all and can't be crossthreaded because an english BB will drop right into an italian shell.The threading is also opposite directions on the drive side anyway.
It's been a while...