Past the power curve ?
I've got a stinger sd"80cc" motor on my board tracker. Have run about a gallon of gas through it @16 to 1.I just swithched to synthetic motorcycle racing oil @ 50 to 1. Engine makes real good power under load but when bike is atwide open throttle and cruising ti kind of fallsoff and surges . throttleback and put load on it pulls hard again. I have 44 tooth sprocket. Should I goto a smaller rearsprocket to keep it in the power band better. My friends bike with 80cc slanthead motor and I think36 tooth rear sprocket seems to pull all the time even at cruise wide/open. Plug is fresh ngk and nicegrey/tan color after hard run. Anythoughts