So I got bored and started a new motor for my Maxi.
Found a old KX80 top end... a Wiseco Yamaha piston (50.5mm) to fit the Puch wrist pin size and a chunk of 1.5" aluminum.
Threw the cases in the mill and mowed the deck off. Milled the aluminum to the correct shape and cut it in half. Lined everything up with the case halfs and welded it togther... added a lot of filler material to allow me to cut in the transfer ports with out breaking out.
Then I did a little calculating and determined the proper case height to obtain a zero piston to deck height with no base gasket and milled the case to this demension. Drilled and tapped the cyl mounting stud holes.
So far I see no reason it wont work....
Next I will rough out the ports on the mill and finish with the hand grinder.
I hope to have it in and running by spring.