What transmission is it?

I picked up a ‘79 250 bottom end. The upper lip over the sprocket with the engine number was ripped off. The PO says it’s a cr but how do I make sure. Is there a cog listing somewhere for these older engines.?

I’m still buying up parts. I took a chance on three ignitions I know it’s a pig in a poke but if one works I made my money back. If all three work I’m golden. I have a larger motoplat 360/390, a 250/430/500 motoplat, and a SEM coming. It’s a good feeling when I need a part it’s on the shelf.

Parts fiche has tooth count . That is 79 cr250

Also each gear has the main part # stamped in it and it should match the tooth count in the parts fiche.

Marty

Thanks I thought someone would know.

This bottom end is complete to the kicker, no cylinder or head. Couldn’t pass it up.

One can put it in low count how many crank turns to get one sprocket turn. Then do in high. Compare to a known one or do arithmetic from the parts sheets and see what matches.