d617

I have 2004 suzuki ltz 400 It idles fine but as soon as you get on the throttle it chokes out. It is not a fuel/carb problem. i have narrowed it down to electrical problem due to the fact that when I get on throttle it draws more power the quad shuts off. I think it is the magneto or voltage distrubtor. Also it runs fine only when the key is turned so lights are on. If turn key to lights off mode. the quad will die. any suggestions