trivia: what stroker is she stradling?

I want to know is, whats that stain at the bottom?

looks like an AS1 or summat from the late sixties early seventies

Looks like a YL1 100 twin.

I want to know is, whats that stain at the bottom?

Yamalube 2, what else could it be, haha

Good Info, because i didn't actually have the answer. . .http://throttleyard.com/2011/07/13/two-stroke-of-luck-four-1966-yamaha-yl1s/