my buddy has a 99 it loss of power, hesitating while riding. The longer he rode it the worse the hesitation got plus the backfiring became worse, sounding like it was through the carburater. Very bogged down. He said that was about it. what could it be?

 

Did he check his air filter?

 

I agree with ftwflh. My '99 500 scram did the same thing. I temporarily removed the k&n air filter cloth cover and it ran fine. I needed to clean the overfilter? and the air filter itself.

Steve Lubecki

 

yes we cheeked the air filter it was drity and had oil in side of it i do rember that it wouldint run right with it off it would spieter and spueter and back fair ? could it be the plug i dont no much about Polaris i no he has had nuthin but problms with it sice hes got it seems like each time he takes it out it breakes.

 

Is it a stock 500?.....or does he have some mods?

 

The 500 wont run right without a filter.Put in a new one and let us know.

 

I can probably save you alot of time.

I have a 1997 500 Xplorer (same as sportsman except no speedo pod on the handle bars) that was doing the exact same thing. It would run well at low rpm's but as soon as you got to mid to high level rpms it would start to spit, sputter, backfire, bog down, etc.

I tried everything in the book. I changed the spark plug, spark plug wire, Coil, CDI, Voltage regulater/rectifier, took apart the carb and cleaned it, replaced the air filter. I finally gave up and took it to the dealer. After two hours they, confirmed what another forum member had told me. The exhaust cam lobe had worn off and also had damaged the exhaust rocker. They wanted $950.00 to fix it. I looked in my shop manual and it looked like an easy project. I bought a cam and rocker from a salvage yard in Minnesota (Mohawk Salvage) in great shape for half the cost of new and replaced it this past week end (3.5 hours). It was pretty easy and would probably take your buddy less time becasuse you have a lot less stuff to take off and put back on.


If your buddy has owned it for a long time he has probably notice a gradual decrease in power over time. I bought mine this past summer and didn't notice it until all of the sudden. But now that its fixed, it is unbelievable!!!!! I am sure it was bad (or going bad) when I bought it.

Hope that helps.

Mike

 

I don't know if it would apply but once on my 400 which is a 2 stroke, it did the same thing i i found that one of the breather tubes was getting pinched off