Bicycle Threading

[Joe_W]

Bottom Brackets: not completely right. I own a bike that has two right threaded threads on the bottom bracket. It is a French bottom bracket (old Peugeot road bike). Not only is the direction different, but also the threading is metric rather than 'weird' inch stuff (like BSA). Also, the inner diameter is about half a mm wider than BSA, so a BSA cup will first look as if it fits and then come loose.
So when restoring an old road bike, sometimes you can get surprises when trying to remove the bottom bracket. I think there were also other types ob BBs that had two right threads...