Hey guy's, I'm gonna jump right to it. I bought an 02' Polaris 700 twin sportsman for $400 from a buddy of mine over the winter. He was at my house riding when a piece of ice got stuck in the fan causing it to overheat.All the antifreez blew out of the radiator cap. This happend about 100-150 yards from my house and he drove it back to my place. He said it was "Blown-up". What it does is...it starts right up with no problem and idles great. It will go fine up to about 8 MPH and the she starts to "Knock". But at the same time, I can put it in neutral and rev it wide open with no knock! ( I only did this to see if it was the same outcome being in gear to being in neutral ) If it was Blown-up shouldn't it knock from the get go and not even move? I'm pretty stumped on this. I checked the clutch and the oil and all seems good. Thanx for any help, Mike.

 

If you're in a "no load" position like neutral it may not not knock as loud or may not even be noticeable if it's a lower rod bearing noise or even piston slap .
Try a mechanics stethoscope (very cheap) and you can pretty well pinpoint the noise. I've got a souvenir rod and piston hanging on my tool box from an old 700 that the guy just rode it until it destroyed the engine. Pulled the piston and rod off the crank where it had just overheated and separated. I wouldn't drive it until you check it out. Could be its just piston slap and you may be able to save the crank and cylinders. Plus NOT a good year for ignition systems with the old Ducati ignition that was changed to Kokusan on later models. OPT

 

Thanks OPT,...I haven't drove it since this problem started, except a few feet from my garage only to get an ear on what was going on. From what I understand, Polaris has alot of problems with these particular machines, but I figured any 4x4 (that does run) for $400 would be worth sinking a grand into concidering how well the rest of the machine is. As for the "Ignition component" I have never heard of that problem and I would definetley like to avoid it. Is it an expensive fix and would you happen ta know off hand where I could find the replacement part? Thanks for your help OPT,..Mike

 

Repair the mechanical problem first! The kit #2202602 (around $450 at Cycle Parts Warehouse) replaces the Ducati ignition that will eventually fail. Comes complete with new Kokusan ignition system. New flywheel,stator,cdi,coil,reg/rectifier, all jumper wires needed and instructions. OPT

 

I'll be bringing it to a Polaris dealer/garage sometime in July to make sure I have enough funds to cover the cost of repairs. And what sucks is the only one thats near me is about 50mi away. I'm also going to make sure they'll install the Kokusan ignition kit while it's in there. Thanks once again for your help OPT....Mike.