Before adjusting the carb, check and clean the air filter as this may be the cause of the problem, if not there is normally two screw on the side of the carb ( if there is only one, then this means it has a fixed main jet, non adjustable ) the screw marked with an L will adjust from idle to half throttle, the H screw ( if fitted ) will adjust the mixture from have throttle to max revs, turn this screw in to lean the mixture, this will increse the max rpm, be aware if you increase the max rpm beyond factory spec it will possibly seize the engine, if you have no means of checking the revs, i would leave it to the dealer
Husqvarna man, January 2010
