Hey, I'm posting just to watch this ok? not trying to hyjack someone elses post.
I have a Huasheng engine too and mine went from bogging down to just plain won't start at all.
Already cleaned the carb, even replaced the carb. Replaced the spark plug and this was a few years back, new plug and new carb got it running, rather crappy, not as much power, but running for another season. Last spring, I BARELY was able to get it started ONCE. It hasn't run since.
I've tried adjusting the valves, (though I'm not entirely sure I did that right, still not quite certain about finding top dead center.)
And after nearly breaking my arm pulling the damn thing, and sometimes it pulls back, the handle is already chipped from it snaping out of my hand violently. So... its been collecting dust in the garage ever since.
So.... if this turns out to be a case of this particular motor is crap, I'll just get a new motor. BUT I'd kinda like to know what the issue actually is otherwise it will just happen again right?
Oh also did a compression check. It's fine.