I have been having trouble regulating the speed of my Jan Ridders 2 stroke engine, so I came up with a simple Ignition cut mechanism.
It is a centrifugal weight that moves the magnet that triggers the hall sensor away from the sensor as the rpm increases. It works well.
It took some experimentation with different return springs to get it to work properly, but as you can see in the video it works well.
I now have a hit and miss 2 stroke![youtube1]https://www.youtube.com/watch?v=2vK77rkgdBg&t=34s[/youtube1]