I decided im about run in (have about 300km on the clock) I went on a 60 km ride today and found that i lost top end after about 10 km. It is there temporarily but it doesnt hold it in fact some times misses a beat. I figure that i may be running a little rich and the plug may be oiling up at full throttle. Plug looks o.k slightly dark. I currently have a .75mm jet in on a 70cc with baffle shortened on exhaust and a few extra holes in air filter. Should i look at leaning up maybe throwing in a 70mm jet?