Who said anything about sticking your fingers near the inlet to disengage the Bendix? The SImjet manual instructs you that the O-ring on the startermotor should be replaced or turned over after 10-12 starts. You can also tell when the O-ring starts to wear if you will listen to the start-up. There will be a squeak or even a small whelp casue by the O-ring failing to release from the shaft end.
I know alot of people who run the newer Simjets and they are a very sound and well running, as well as dependable engine.
TOmmy