I've got a 2000 Polaris 400 4x2 that I'm just starting up after setting for a couple of years. It ran great before it set and it still starts and runs good but at idle there is a new noise coming from the piston area. Sounds almost like the piston might be rubbing or something, not really a metal on metal sound though. I pulled the spark plug and noticed some rust on it so I'm wondering if some water or antifreeze got in there and rusted. It has always been stored indoors. Any other ideas? And if that's what has happened is there an easy way to take care of that. Thanks

 

check your counter balance

 

How do I check the counter balance?