THE PROBLEM MIGHT NOT BE ONLY ELECTRICAL. YOU MIGHT HAVE WORN CARBURATORS. TO FIND OUT IF IT´S ELECTRICAL OR NOT, REMOVE THE SPARK PLUGS. HAVE THE SPARK PLUG PIPES ENGAGE WITH THE SPARK PLUGS AND HAVE THEM GROUND TO THE ENGINE IN SUCH A WAY, THAT YOU CAN CLEARLY SEE THE SPARK PLUGS NOSES. CHECK EACH ONE OF THE PLUGS BY PRESSING THE START BUTTON (THE ENGINE WILL START TURNING).THEY´LL HAVE TO GIVE BLUE SPARKS. IF NOT, THE PROBLEM IS ELECTRICAL. IF DOES, THEN YOU´LL HAVE TO CHECK THE CARBURATORS.