It is a 1988, with a fly wheel weight.
Bore is .040.
Water pump spouts have been repaced with poly epoxied in place.
Swing arm pivot has been drilled to 13/16" and subsequently broken the left case half. I have since lost the busted off piece.
Also I have a jug from a 1986 CR 500. Not sure what the bore is offhand, I'll have to measure it.









