also, there is another screw you could adjust that may be causing the governor to hang, where the throttle cable hooks to the control panel (on the engine) there should be a phillips head screw poking out from that cover, you can use that to raise or lower the RPM as it presets the tension on the governor spring. The manual calls it the Accel Lever screw.
Engine fires one spark per revolution as it is a fixed coil and magnet on the flywheel. just like a lawnmower.