Here are some more pictures of the Engine in the other thread.

and more

and some more...

I like that custom counter balancer cover.

CO

I didn't know they used a Yamaha rod..maybe that's why you need that thicker spacer plate.

Yeah probably a long rod Engine, I have seen 350 engines built like that before, weld on a Kawasaki reed cage flange, runs a Kawasaki reed cage, weld on a new exhaust flange, change the exhaust port to a large non bridged design.

Cylinder skirt looks scary thin.

Notice the relief cuts in the crankcases to allow clearance for the piston skirts on each side. Check that clearance when installing a new piston.

See if you can find numbers on the rod and document

Document the numbers on the piston. If you split the cases try to get a pin diameter on the big end of the rod and or inspect to see if its been machined out larger. See if the crank cases been clearanced for the rod.

I think I have a set of old stock cases and a crank I can measure from if you need to verify crank pin diameter or need to compare for case modifications.

I sent this Engine to Methodical to go through for me. I can update once I get more info.