Depends. IF the carb has adjustable jet(s), set both to 1.5 turns open from fully closed. This will get it started. Let it warm up. Back off the throttle until it starts to falter. If it goes all the way down to idle, so much the better. Snap the throttle wide open. If the engine accelerates smoothly, the main jet is set. If it hesitates, open the main jet 1/4 turn and try again. Now, back off the idle to obtain the disired idle. if the engine falters adjust the idle jet to get the smoothest operations repeat idle adjustment as necessary
Phil Saunders, July 2011
