magnetos are very simple. They either work or they don't. They create their own energy (spark) and therefore don't need an alternator to provide spark like a standard ignition system. THere are two manufacturers currently making mags. Vertex and Mallory. For your application, I believe the vertex would be the best. This mag comes two ways, internal coil or external. Both will work, but the external coil will put out more spark. I run a mag because they are simple, reliable, and cheap. For more info, call me ..