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Discussion Starter #1
Anyone notice anything unusual with their valves?
Mine look as though they were on the verge of melting. The exhaust side(bottom) looks as if the nicasil is worn off and a lip is starting to form. Also the spacer under the bellow shows signs of wear like it was loose but it wasn't. It ran fine but if left unchecked I think that lip would start to hang up. Btw 800xc 02
Anyone?? Thanks
 

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The problem you are seeing is from detonation. Polaris is seeing this on the 7&800 when the tps setting is above 3.7 What is ocurring is midrange detonation, the exhaust valves are not opening until 6000 rpm with the stock spring and the valves themselves are getting red hot and causing pre-igniton of the fuel in the cylinders. You can change your EV springs to open sooner or back off your tps setting to stop the problem. Look at the outside corners of your valves, do they show excessive heat or blued at all? I am sure a bulletin will come from Polaris on this issue in the near future  
 
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