ok, I pulled the manifold to look at the ports and had some interesting observations.
The ports and gasket aligned very good.
I was suprised to see 3 rings at the top of the piston. The top one was bright and the lower ones were dark.
When I ran the piston to TDC, what looks like another ring groove appeared at the bottom of the port,on the piston skirt.
I've seen motors that used a bottom ring like this. If this one is missing a required skirt ring, that would explain my extremely low performance, 10mph cruise and not enough power to take off at all without help. Cranckase pressure would be leaking into the exhaust port.
Hey Cannonball, did you pull your jug? If so, what did your piston look like?