Over the summer i bought a 1996 Polaris Ultra Sp 680. It has tripple pipes so i assume it was clutched and jetted. I had it out on the trials acouple times this year for short rides maybe an hour. We havent had much snow. It ran great no problems. Now we got a decent storm. So i had it out yesterday. It ran great and strong for an hour but when i slowed down it lost power backfired and died. Couldent get it to start back up even with new plugs. Plugs in it were tan/brown. Got towed back to truck. Started rite up. Anybody have an idea whats wrong? I dont want to get stranded agian. Any help will be greatly appreciated.