[canadian_fisher]

Hey Champ 55,

Did you do any service work to the engine lately?
Sometimes even the simplest of repair could have cause another problem.

My guess would be a bad ignition switch. (not sending kill signal to switch box).

Please let us know what you find . ....... CF

[canadian_fisher]

OK.......... here's how I would diagnose it........

At ignition switch, remove ONLY the Yellow / Black wire that goes back to the CDI (and probably fed to OR from Kill switch).
When the motor starts, touch the Yellow/Black to the BLACK ground wire as see if she stalls out..........
BINGO........ bad switch.

If that doesn't work, you'll need to do that same directly at the motor.......... now that will require a Service Manual.....

Good Luck. CF