I wonder how a Club Car Golf Car engine would work?
It has a clockwise rotation so that would put the drive pulley on the same side as the Simplex. That may make it possible to use the Simplex transmission. The head would be toward the front wheel for a nicer looking setup. I think the engine would look good with the fan removed, as it wouldn’t be needed for cooling.
There are a couple of displacements available between 200 & 300 cc.
I forget what size my carts engine is but it will do 35 with 500 pounds on it.
I think I just talked myself into it if my engine turns out to be un-savable.
Gramps