Pinching the fuel line is an effective way of shutting off your engine. As a test, you can tell if you are running lean or rich by how long it takes to shutt off. If you pinch the fuel line and it shuts off quickly, I believe its lean, if it takes too long, then its rich.

In my opinion, 5 seconds is quite too long, 3 seconds is ideal, specially if its done close to the carb, the further away the pinch from the carb, the longer it takes to shut off.

Its not the best way to tune. But along with other indicators like the exhaust smoke, and sound. This could help you fine tune your engine.


If you use it often, its not necessary, but it wont hurt to do a preventinve measure. I put RAO after every run just because I dont know when I will run it again. Remember that the rc fuel has oil mix in it.

5 drops of oil in the carb is enough. Then run the roto start for about 2 seconds w/o the glow plug igniter but with the glow plug (make sure there is no fuel). This will distribute the oil inside the engine. No need to remove the glow plug.