An old mechanics trick is to try to slightly tighten the BB first and then try to loosen it. Don't use frame destroying gorilla strength to tighten it of course but some leverage is OK. Also set some ice cubes in the BB for at least an hour and then pour some boiling water on the outer BB shell and immediately try to loosen. Safe, won't hurt anything.
Last edited by Crankycrank; 07-20-21 at 02:01 PM.