Why Is It Called a Nipple?

by Chikashi

I recently enquired about some specs on rims for tubular tyres. Given that the tyres will be glued on, I wanted to make sure that the rims are made to take external, not internal, nipples in case the wheels need to be trued at any point after the tubs have been mounted. Outies, not innies.

Someone called Nancy replied, so I’ve been exchanging emails with a woman about nipples, amongst other things.

She said that I can have external nipples. I thought, I love it.

I believe that the French simply refer to it as écrou, which means nut. Terribly unimaginative, but ruthlessly efficient.