I bought a 2003 Polaris Predator 500. I listened to it run from a cold start, I test drove it up the road and it seemed perfect. I loaded it up and brought it home took it up the road a few times and it was running fine, I pulled it out of the garage the next day to go for our first trail ride. On the way to the trails I reached top speed as soon as I heard rev limiter I let off the throttle and it back fired and died. Would not start back up for nothing. I got it home and unplugged the all the electrical connections and plugged them back in and it fired right up and sounded good. This morning I went out and it started then died and now all it wants to do it crank over and then the battery dies. PLEASE HELP!