there are two screws on the side (left looking into the bore) the larger screw is your idle speed set screw. turn this screw clockwise 1/2 turn at a time. when the idle reaches the rpm you want, turn the smaller screw 1/4 turn in either direction, and note any rpm changes. if your rpm's rise turn the speed screw to compensate. the smaller screw is the idle mixture screw. the goal is to get the best idle mixture screw setting, and use the speed screw to adjust final rpm's. i would sugest you replace the fuel filter BEFORE adjusting the carb. once you get the best mixture setting turn the mixture screw 1/8 turn counter clockwise, and again set final rpm's with the speed screw.
