Great looking Spit!!!!!!!!!!!!!!!!!!!
I have kept my mouth shut about over heating engines. I have never had one over heat except one but it was caused by a crash. I have pulled the engine apart and measured the crank and rod to see if I had bent them. According to the service they are fine but when I fire it up it cooks itself so fast it dies in about 15 or 20 seconds? I have reversed the piston and rod giving it a try but it reacted the same way. This was caused by a crash and not an over heating lean problem, I have never done that to an engine.
This is an SK .91 engine, I like them a bunch but at $100.00 I'm not going to over think it or keep working on it. The OS is worth the time and money. I would measure the rod and crank then do a visual of all parts. I think I would ask Bill Baxter what the correct size of the piston is too and measure it and then measure the sleeve too. Often when you over heat an engine the piston seizes and will leave aluminum on the sleeve.
You really can't tell the whole story looking into the port, you have to strip the engine down and look and measure things!
There are a lot of things that can happen to an engine if you over rev them and none of them are good.