I need help

| July/August 1974

Pictures are two views of an engine that I got a couple years ago. I can't find a name for it. It has four bolts to hold the igniter plate on. The odd thing of it is the carburetor goes in front of the head just above the exhaust valve. The intake goes in through the igniter hole with the spring in going straight out right side of engine. Gas Tank and Base The water hopper is cast by itself. The cylinder and base with main bearing mounts altogether. The water jacket just slides on over the cylinder with jacket on the back then head goes on to hold water jacket in place. Please help!