I have about 65 miles on my new 500 H.O. with no trouble except a low idle problem which I fixed right after I bought it 6 weeks ago by turning the idle up just A little bit.I thought every thing was running smooth until A couple of days ago.I was riding at about 35 miles an hour on a flat road I topped A hill and let the machine coast down the other side when it slowed down to around 10 miles an hour it started back firing out the exhaust pipe.It was cold outside around 40 deg. so I thought maybe the cold air was causing the problem,so I rode it again today at around 65 deg. outside and it started backfiring again at about the same speeds again.I always let the machine warm up good before riding, and it seems like the problem shows up after about 15 min. of ridding.Has anyone had or heard of this problem before.

 

Mine would back fire and die when coming to a stop,I couldnt get it to idle right with the idle adjustment. The problem was the throttle cable was out of adjustment. Just below the thumb throttle the cable runs down the handle bars, there in the cable is a place to adjust the throttle cable.Just pull the rubber cover back and adjust with fingers.That may not be your problem but it was mine for about three weeks before I found it.

 

Sometimes it goes dead if you come to a stop or back up using the reverse override switch, also I have noticed a erratic idle sometimes and then sometimes it just goes dead own its own.I think I have A carb or E.T.C. problem

 

Packrat has a very good point. My magnum did the same thing for a while, I thought it needed a little idle adjustment. But first I called my dealer and he said it is the throttle cable. After a while, when you use the quad for a while, the cable stretches and gets some play in it. The quad thinks the throttle is stuck open so it shuts the quad off. So doing as packrat said, you should be able to tighten the cable, and solve the problem, but sometimes, if you don't catch it in enough time, it causes the plug to foul, and some other miner problems. So you might want to check that, now, if the adjustment doesn't work, pop the top of the throttle box off, and make sure the cable is seated properly too, too much play can cause the cable to almost come off.
Hope this helped

 

Hey, PACKRAT & POLARISMAN thanks so much for the advice after I read your replys I got the POLARIS manual out and read about the throttle cable adjustment the manual stated that there should only be about 1/16" to 1/8" free play in the thumb lever for proper operation so I went and checked the free play on mine and found over a 1/4" of play in it, this is almost double from what the manual says is correct.I will adjust the cable and let you know if this works!

 

Adjust it while engine is running.If you go the wrong way engine will die the other way it will rev up.

 

Hey, I'm glad I could help out.
I was playing around with my adjustment and accedentally tightened the cable all the way, the throttle was wide open, let's just say I had a little suprise when I cranked it up. Anyway, that should solve your problem.
Let us know if you have any other questions.