I did run a kill switch. The kill switch was designed to cut the engine if loss of signal occurred. I also had the ability to remotely shut the engine off. In addition to the spring. I don't take chances with these models. The kill switch I used was not designed for it specifically, since gasoline powered 1/5 scalers were pretty rare back when the 5b had come out. I had spoken to a company that designed switches for rc tanks and such. I told them I wanted a switch that was normally closed, so that when it lost signal or power, it would close and short the ignition (kill switch). I tested it fully, with the car on a stand. Loss of signal, loss of battery, etc. Every single time it worked. I am just letting you know I am not some hack as you're inferring.