https://www.youtube.com/watch?v=rbH9yp2kwM8

https://www.youtube.com/watch?v=MxzW9aYA_6U

If the spark plug electrode is wet or black, as compared to beige-brown, excessive fuel may be bypassing the carb via a deficient vacuum petcock diaphragm.

https://www.youtube.com/watch?v=FnhSfgS0x4Y

The spark plug seemed to be fine when I took it out, a little darker than it probably should be but the carb is definitely running a bit rich.

Adjust the valves, and then evaluate.

So I know this is really late but I basically decided to rebuild the whole engine while I was dealing with this just to make sure it wasn't compression since I was planning on doing a big bore kit (47mm bore and head) anyways with A9 performance camshaft. I also replaced the final drive gears to a 49/17 ratio on top of putting in a new performance clutch and variator. I also replaced the the CDI and ignition coil with their performance models (the blue racing CDI and orange ignition coil.) I set the valves to .003 intake and .004 exhaust but the scooter still didn't work. After checking spark I was at a loss as I hadn't considered it to be a fuel problem but lo and behold the issue was the petcock going bad. Once that was figured out I replaced it with a new manual petcock that had less chance of failure (and was also easier to see fuel flow) and the scooter started running again. Now with all these mods I just need to get the carb and variator tuned properly and I should be seeing some decent speeds after. On a flat I was only getting 43 top speed but the acceleration is pretty solid. The scooter doesn't seem to quite be getting into its ideal RPM range but I won't be able to tune it properly until I'm able to get my new tach/speedometer installed which will be saved for another weekend project.

At least it's running. That's a good start.