I had a F7 in the 70's and had the good luck to have a father-in-law who was the shop foreman in a Harley/Kawasaki shop. He shimmed the barrel up 1/4" and shaved the same amount off the top ,which allowed the piston to completely clear the exhaust port. It made a noticeable difference in power.

arrghhh... how do you get things so cheap in the states. the way she sits as you got her.... a grand easy up here.

So exciting!

That was my first motorcycle. I bought it from a pawn shop in 92 for $200. I just bought another one last week with 1000 original miles--in much better shape than my first one! They are amazing bikes--21.5 HP from the factory and so light! I wouldn't worry about the induction (rotary vs, piston port vs reed). Whatever the issue is, I'm sure it's traditional--spark, fuel, compression. You know you have good compression, so I'm guessing it's a fuel/spark issue. These things are CDI six-volt--pretty reliable, but some little things that could go wrong. I just saw it's been nine months since you posted the video. Did you get it sorted?

Hi, just a little thought, you seemed to get a lot of smoke for a short run of the engine, in my experience you might be getting too much 2 stroke oil going into the engine, i would adjust the oil pump a little & check to make sure your spark plug is the correct one, i have had two strokes that would not run until it had a new plug then all was well for a few months then the plug would go again, a new plug and all fine again for a few months. 😲