some things to check...
malfunctioning ignition switch, shorting wiring harness, malfunctioning emergency stop switch, defective tether or tether disconnected (loose wire), throttle monitor switch out of adjustment or malfunctioning, bad plug wires or spark plug caps, CDI defective, charge coil in the stator defective...
some are easy, some are expensive... I work from cheap and easy to hard and expensive
On my 94 580, my problem with no spark was throttle free play and the throttle position sensors. You can try jumping the throttle position cable to see if the sensors are out of adjustment... AC put a throttle cable jumper in their tool kit with a lot of the sleds because that is pretty common.
hope that helps!
Dan
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Rebuilding the fleet!
2008 RMK 600 155", 2006 RMK 600 144", 98 Indy 440, 95 Prowler 550 2-up, 1990 Indy 650
RIP, destroyed by fire 1-22-2008

04 RMK 800, 05 RMK 600, 02 RMK 800, 97 RMK 700