My limited experience with air-cooled two-stroke motors is that powerhead overheating is normally caused either by plugged or broken fins, or lack of shrouding to direct the air flow over the cylinder fins.
Some of those air-cooled jobbies had water-cooled exhausts, but I’m not aware of that being the case on a jet-drive type.
Didn’t see anything in this flyer about water-cooling anywhere
Hope this helps.
Best,
PM T2
PS – what are your overheat symptoms, and what spark plug are you using?
He's livin' in his own private Idaho..... I hope to go out quietly in my sleep, like my grand-dad did..... and not screaming, like the passengers in his car...