- Square taper BB keeps coming loose
fitted a new square taper bb to my hack bike only to find the drive side keeps coming undone
refitted it quite tightly but again, its come loose within a few hundred yards. Got a feeling I did the NDS cup first then fitted DS & bracket…should I do it the other way round?
any reason why it would happen? Wrong axle length mebbe? all I can think is that the NDS pedal is somehow turning something that then loosens the DS…no idea how tho!Posted 4 years agosimon1975Subscriber
The driveside threads are presumably the actual body of the cartridge? That needs to be done up fully until it contacts the frame (no need to go mad with high torque, though). Then fit the NDS cup fairly firmly, and not too firmly at all if it’s plastic. In steel frames I lather the threads in copperslip first, not tried loctite there…
And when it comes to removal, undo the NDS cup first.Posted 4 years agotoppers3933Member
It’s because you tightened up the nds first. You should tighten the drive side first then the nds. It’s the drive side that tightens against the frame the. The nds tightens against the end of the bb shell. So what’s happening is the bb is moving in the frame because its not actually tight. Undo the nds, tighten the drive side and retighten the non drive side. If you no already damaged it (too much) it should be fine.Posted 4 years ago
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