1997 polaris sportsman 500 engine noise at idle,posible primary clutch noise

SOURCE: 2001 Polaris sportsman 500 magnum 4x4, speedo dont work

I'm not sure but it might be the sensor on the right front wheel disk

SOURCE: replace drive belt on polaris sportsman 500 1996

Usually a simple process. Remove the large oblong shaped cover on the left side of the engine.inside is the primary (small pulley) and secondary(large pulley) drive with the drive belt running in between them.Force the large pulley apart(best done by hand) allowing the belt to drop down to its center and then using the resulting slack to pull the belt over the primary pulley and thus removing it.Rotating the pulley(s) by hand may aid in this process.(think about how a bicycle chain is put back into place after it has fallen off.Same basic principle) Putting the new belt in place Reopen the large drive again(spreading it apart) and place the belt onto it first then over the primary.(again turning it by hand much like the bicycle idea).When all is said and done check the seal on the cover and make sure it is in place(if damaged replace it.This is very important to help keep contaminants and water out of this area.)and replace the cover tightening the bolts from the middle outward towards the ends.This will also help seal it up properly.

SOURCE: Service manual for a 2006 500 Polaris Sportsman HO

I have a 2006 Sportstman 500HO ATV, EFI. Sometimes it will run 100% correct, other times it will start, idle fine but then when giving it throttle will will start to surge almost like it's hitting a rev limited. Sometimes it will backfire and stall. I already replaced fuel filter, flushed the fuel lines and gave it fresh gas and installed a new spark plug, but no good. I also checked the throttle switch and it's not making contact to stall it. I download the service manaul and tested each sensor and they tested fine which is probablt why I get no check engine light.
This ATV is mainly used to plow snow in my driveway, no salt. It's used around my property but very lightly. It's still as clean as it was when I bought it and it doesn't have but about 40 hours on it.
Polaris 500 HO EFI 4x4 ATV: Vin# 4XAMH50A56B707664 purchased 6-8-2006

[email protected]