300 fourtrax runs good higher rpm, but dies when warms up

Thanks for the reply Goob, that's what I thought, but I'll have to set up a bottle of clean fuel with a filter and try it that way, will do that later today. I think I did, did it the way i always do and it seems to work, i use torch tip cleaners, which are basically the same as Honda's "jet cleaners", didn't change seals, but none leak, and the only o ring was on the pilot screw, seemed pliable and fit nice, let the carb soak in napa's carb dip for a good while, then sprayed it, and cleaned it pretty well. And counted the turns of the pilot screw and put it back to where it was, and tried turning the pilot screw a few ways to see if I could get it to run differently, no change. I did nothing to the choke, all I checked was when I engage the choke, that the black plastic with a needle retracts and lines up straight, which it does, what else is it supposed to do?is there a way to check if the choke is not working properly? The plug was wet, smelled like unspent fuel, which I found odd.