[hotrod]

Well I got the exhaust valves out of the 2000 XCR800 to clean them up for the season. I will need to replace the gaskets this time. Since Im going to the dealer anyway I recalled I wanted to know if the performance can be changed or altered by using different springs in the valves. Any one seen or heard any thing on this yet.

 

[EFI600]

I've seen aftermarket valves, but I haven't seen aftermarket springs. Maybe try to contact a aftermarket Polaris company.

 

[razorsharp]

I had a buddy that changed his springs because he was running at 6k ft. I think there is different factory springs for elevation, but I've never seen any for performance gains.

 

[Alaskangold]

When we went down to the Yukon last year for Ice and Drag Races I talked with a guy who was running a 00 or 01 600 XC. He was saying that he messed with his valves and made so they either never opened or were open the whole time during 660' drags. He was saying the difference between stock and after was tremendous, don't know if this helps in anyway..But I guess it can be done?

 

[MegaMan]

Switching springs would work. Couldn't a person just adjust the number of turns on the plastic housing that the valve is mounted in? I realize that is used for fine tuning and syncronization of the valves, but what if you adjusted them both in or out more to raise of lower the exhaust port slightly? Also, if you wanted a tighter spring, perhaps a person could add some shims behind the spring to make the valve open earlier. I don't know for sure, i'm just throwing out my ideas.

 

[hotrod]

Thanks for the replies guys,I will have to look into that further. I always assumed that you tightend the blue plugs that hold the springs all the way. Any one else got some info?

 

[hotrod]

Ok, I went to the dealer and asked about the springs. you dont adjust them at all and you can get springs for improved bottom end or improved top end but not both.

 

[ZRT600]

I've heard of it, but I don't know what springs work best.

 

[madcow]

yes changing springs can change the rpm at wich the valves open.