Ok guys, there has to b someone in this world that knows how to fix this 2001 ranger 500. Blows carb off intake boot while cranking. New plug, boot, coil, cdi, pickup coil, stator, flywheel, cam chain, and ignition switch. Pulled head and went thru valves. Been thru carb 5 times. It will crank and run but has a bad miss. Been to 1 bike shop he gave up. Just got it back from Polaris dealer after 3 wks, they gave up. Would appreciate any help. Thanks.

Was the cam replaced? Did you check the cam detent lever and spring along with the small bearing that holds the exhaust valves open a bit? Right flywheel and stator for the 500 and not for the series 10 425 Ranger? Plus does your model have a glove box or just a blank space?

Thanks for reply.No cam was not replaced,looks like nu, checked with caliper.Nu flywheel and stator has same part # as old 1. No glove box. This this thing is unbelievable. Thanks for any help.

OPT,would it be possible to talk to you by phone?

Sorry,I'd have a 100 calls a day if I did. You have the Series 10 and I still can't help but think something is isn't right with the electronics. They had the the 425 and 500 both in the Series 10 and don't know where you got the parts,but if the stator happened to be swapped with a 425 that could explain the backfiring as they were different,plus there were ongoing electrical changes. Dirt Cheap Yamaha, Honda, Arctic Cat & Polaris OEM Parts & Accessories – Cycle Parts Warehouse
Plus what did you come up with on the cam shaft lobe measurement?

How can I tell the difference between the 425 and 500?

Look on the bottom of the cylinder. Will show either 425cc or 498 cc for the 500, Plus if you're not sure check the vin number here.Polaris Off Road Vehicles: Four Wheelers, RANGER RZR Side by Side ATVs and UTVs Plus vin number is under the hood on the left.