I've found that if you trackstand or resist stop a lot, and have an old cup and cone BB, the fixed cup can come loose, even on English or Swiss threaded bottom brackets. If it is the fixed cup coming loose, the solution generally isn't loctite; instead, find a shop with a Var30 fixed cup tool and have them crank the fixed cup on hard. A regular tool can't torque like this one, believe me. I've never had one work loose after this, be it French or English... actually, I've never had a French fixed cup come loose at all because I install all my fixed cups with this tool. I have had to retorque a couple of English fixed cups, tho. It's really probably not a purchase option for most cyclists, about 200$ Ithinks, tho they do show up on ebuy now and again.