To set the idle air fuel, get it to is somehow. Once somewhat warmed up, get the air fuel screws to say 1 1/2 turns out. Both equal. Then turn both screws equally in or out half to 1/4 turn at a time until you get the highest possible idle. If you have to turn the screws out past 2 1/2-3 turns you prob are too big. Doubt that's the case. If you're in past 1 turn or so you are prob too small on the pilot. Which would be my guess. Once set it should rev from idle pretty crisp.