Fbird,
I just happened to own one of those, but I sold it a week ago. Mine ran great but then after a while it started to bog and just didn't have any power. I bought a new spark plug and that didn't help one bit. Then I started to think and pulled off the Pre-filter and the air filter. I bought new one's and when I took it for a ride it nearly threw me off. See if that might be the problem. That is a bad machine and they run great too, I've had mine past the 60 mph. mark and still had a little throtle left and they are a very good work machine for a 2 Stroke.