While we're on the subject of magic formulations, what is the best penetrating oil for loosening frozen BB cups? I've got a mid 70's Peugeot PY-10 frame with a Stronglight Competition fixed cup that refuses to budge, even when I hammer on the end of the lever bar of a VAR industrial-strength BB cup remover. Yes, I did confirm it is French thread and therefore right-hand thread. This one is fairly easy as it is marked 35 x 1, rather than the cryptic rings on some Stronglight cups. Of course 35 x 1 could also be Swiss, but I never heard of a Swiss-threaded Peugeot.
Regards,
Jerry Moos