I use the kill switch for a starting routine for my hard to start in the cold CB500. Open the kill switch, choke full on, open throttle wide, hit starter for about 5 seconds, close kill switch, crack throttle just a bit, hit starter button and off she goes. I am not quite sure what the logic is, but it does make it easier to start the old girl. The procedure was suggested to me by my brother who is a motorcycle mechanic and old bike aficionado.