Bicycle Mechanics - Italian Bottom bracket locked on fixed gear

I have a giordana frame so I put in a shimano italian threaded bottom bracket. It's my first fixed gear, and I'm liking it, but today when I was riding, as I was slowing down I suddenly felt the rear wheel lock up. I took it off the road and the cranks won't spin. i inspected the bottom bracket (not the insides) and it looks like one of the cups of the bb is protruding more than it should (if it should at all).

so, what's up with this?! will i need to replace my bb? it was new. is this normal that it just lock up? i hadn't noticed any problems with it; no noises, cycling was smooth, no indications. can anyone tell me what's going on? thanks!

eoin

got this fixed tonight at sopo bikes in atlanta and while i was there i asked about why/how it happened. apparently bottom bracket loosens itself in italian bikes. no lockring either. i was told i may have to take off the cranks and check the bb is tight about once every month. does this sound right?! i'm looking into buying the tools now. thanks.

yup, that's exactly what happened, and yeah, you should check it pretty often

Italian bottom brackets have both cups right hand threaded and the drive side cup has a natural tendency to unscrew unless torqued down VERY tight. The recommended installation torque is over 300 inch-pounds and you are unlikely to get it that tight unless you have a torque wrench to guide you.

Some mechanics use blue (Grade 242) Locktite on the threads which can be useful but shouldn't be necessary if the installation torque is sufficient.

One time I was going down hill and all of a sudden my rear wheel locked up. Turns out that the cup with a the lock ring was screwing itself thight into the BB. My advice is to screw the the lock ring tight and you will be fine. Also thighten the cup on the drivetrain side because that one unscrews itself.

does the locktite have any negative effects? do you know how long it would last?? thanks.

does the locktite have any negative effects? do you know how long it would last?? thanks.

with blue you'll need to put a very large amount of force on the cup to remove it. with red you'll need to fire up the torch. a less extreme alternative would be a combination of teflon tape on the threads and a lot* of torque.

Locktite lasts forever or until you remove the cup, whichever happens first. You will need a lot of force to remove the cup if you use Blue Locktite but, that's why it's there.

As noted, don't use any of the high strength grades of Locktite (Locktite makes many grades for various applications) or you will need heat to remove the fitting and they aren't needed for bike applications anyway.

GO with a cartridge BB when you have the chance, unless you really really like cup and cones.