Bicycle Mechanics - crack in bottom bracket plastic cup   john h
07-22-10, 11:03 AM I overtightened the plastic cup side of my
b/b and cracked it a little. Is the b/b still rideable?
07-22-10, 03:17 PM As long as there is no wiggle in the bottom
bracket, it's still ridable. Not ideal, and you should check it
every now and again to make sure it isn't getting worst, but it
won't lead to spontaneous human combustion.  07-22-10, 03:22 PM
I'm with fuzz2050. If the BB is still rigid and without free
play ride the bike and don't worry. Eventually it'll get worse
and need replacing, but that might be a long ways out, if ever.
Check it often early on, and if it's stable you can stretch out
the interval between checks.  07-22-10, 03:43 PM +1 on it's ok.
As long as the broken pieces don't fall out, you should be good
indefinitely.  However, if you do remove the bottom bracket, you
may have problems removing the broken cup from the frame
depending on how it broke. Been there, done that. You can
probably get a replacemen