A powered device may include an engine, a mobility assembly operably coupled to the engine to provide mobility of the powered device responsive at least in part to operation of the engine, a working assembly operably coupled to the engine to perform a working function responsive at least in part to operation of the engine, and a key-operated combination ignition and speed control assembly including switch circuitry configured to control both starting the engine and selection of different selectable positions corresponding to respective different operating speeds for the engine.