I bought this yammahopper and spent quite a-bit of time working on it I finally realized that It needed new piston, rings and a good honing. I assumed that this would fix all however I put er all back together and when I have it up on the stand it will pick up and that back wheel will haul a$$ however when I sit on it the thing sounds like a am not even giving it gas. I really want to ride this thing but I can't figure any of it out. It has new gas and 2 stroke oil. I drained and cleaned the tank. the engine is almost all brand new. I put a new plug in it and it seems to spark fine.( what plug # do you use(NGK)) It might be too hot. The plug doesnt get black and the think doesnt seem to be running rich. If you have any ideas let me know. Thanks.