Check there aren't any twigs or other debris preventing the governor from operating. The governor arm and linkages can be identified as those parts which extend out from the engine block.
There should be 2 adjustment screws on the bracket at the end of the throttle cable at the carburettor. These act as stops to limit the movement of the bracket, one is for setting the idle speed of the engine when the throttle control is set to low and the other is for setting the max speed when the throttle control is set to high. Set the throttle to high and examine the carburettor, the screw to adjust is the one which is preventing the bracket from moving. Turn it and monitor the effect but remember the initial position so that you can get things back to the way they were if necessary.
Euge, May 2011
