Yo guys, Not to sound stupid but the screw on top with the spring sets the carb throw the low end needle (idle adjustment screw is in the center of the carb linkage arm on the side of the carb. Follow thsteps for seting the barrel to 1 mm open then.........

Close the idle adjust screw, hook up a piece of fuel line to the nipple blow through the fuel line then back the idle screw off till you here a small hiss in the carb ( from you blowing) should be about 3/4 turn. but do it the hiss method.

Tom