ORIGINAL: JAG123
I turned it out more when I was working on it because I got a lot of unburnt gas out of the exhaust, and thought it was running too rich.
When you turn the needle valve OUT, you're making it MORE rich.
That slime is not unusual with a 2-stroke, but if you can't get it passed half throttle, the mixture is wrong. That, plus the slime, plus the spinner coming off tells me that the mixture is too rich. Next time, start the engine, bring it as high as it will go but still run, then turn the needle IN a little. Let it blow out any built-up fuel and increase the throttle some more.
Once you get the throttle fully open, adjust the RPM to peak and then back it off (Turn thr needle OUT) until you just start to hear the RPM decrease.