Method for controlling the speed limit of a combustion engine

A combustion chamber mounted with spark plug is controlled by an ignition device. A speed control unit is provided to control speed of combustion engine. A speed trap circuit is provided to limit speed of internal combustion engine to a speed limit below stall speed. The speed trap circuit is turned on and the speed trap circuit is switched off until operation of engine after generating a deactivation signal, when starting internal combustion engine. The deactivation signal is then generated when a mode change signal of the implement is detected.