Rad Valve Problems

[XRIowa]

OK I have a 2001 KDX 220 FMF Gnarly woods pie and power care 2 silencer.. I just installed a Rad Valve and the bike runs like crap!! I am going to follow the instructions that came with the valve and go leaner 2-4 sizes..
I have never messed with needle clip position so I thought I would raise the clip from the 4th position to the 3rd does that sound right...
(BTW I am right around 300')

 

[QLD_KDX]

Can't help you - mine runs great!
What you propose sounds about right though, it needs to be a little leaner. Not knowing what jetting you have at the moment though, I would just go down one size at a time. Raising the clip will lean it out a bit, but if you have stock jetting then simply adjusting the needle clip may not do enough. I would move that clip to the centre like you said, then try one size leaner on the pilot and main until you're in the ballpark, then fine tune with the clip from there.

Hope this helps,

Andrew

 

[Green Hornet]

Raising the clip or lowering the needle will lean the carb. Thats OK. Try a smaller main & pilot and adjust the air screw. Do one at a time starting with the pilot

 

[Sunny State KDX]

XRIowa I ended up with a 142 main, 40 or 42 pilot (40 ran perfect on the old top end, new top end and I had to go back to a 42 as the bike wanted more fuel down low), stock needle in the 2nd from the top position and the air screw on 1 3/4 turns out. I'm at sea level and rode this same combination at well over 1000 feet with no change other than a 50/50 100 octane mix w/ prem pump gas for safety. Down here at sea level Pump gas always.

BTW I have the same setup as you, Rad Valve, FMF Gnarly pipe and Power Core 2 silencer.

 

[StrokesX2]

I'm at 5500 feet and ride up to well over 10,000 feet. Higher altitude does two things that are related. Thinner air richens the mixture and lessens the chance for detonation. You can get buy with a lower octane gas, though I always use premium.

 

[XRIowa]

Thanks guys, Like I said I moved the needle to the 3rd position and I dropped the main a size or 2.. Ran real good yesterday