Make sure the in-tank fuel clunkerfliter is clean and clear then tweak the carb to perform...On the top of the carb within the inner core of the brass sloted screw is your low speed needle which also controls highspeed mix aswell...with a small jewelers screwdriver turn the screw counter clockwise 1/2 turn,,,set the high speed screw or fuel limiter screw out 1 1/2 turns out.....Make sure youre running a NGK BPM7A or 6A plug gapped to .030"