ahh that explains alot, your burning them downand or having dcs problems on the needles, thats where you need to focus your attention then. Your in the big timing curve of the viper cdi box , this is why you can run it wide open and be fine. the main is plenty rich but the needle is too lean.
so put the needle out at 3.5?...we havent burnt them down yet...except that one time and we never got dcs problems then
and am i better off changing the mains or leaving them?
and am i better off changing the mains or leaving them?
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leave the mains, your light is coming on in the needle circuit, thats where you need to richen it up.
dirtjumper895
New member
When your mentioning having the needles in the 3.5 position, what does this mean? I have never heard of a half position on a needle? On my 04 Viper's needles, i have the clip in the lowest position, hence raising the needle as high as it will go... I call this the 5th position.... Am i looking at this wrong? Please Explain.
the shims in the carb allow you to go 1/2 a clip to fine tune the carb precisely, instead of using both a shim on top and bottom of clip you can use both up top or under clip for a half position. i am talking about the small white plastic shims on the needle.
dirtjumper895
New member
Ahh i see now... When i removed my needles to switch position, i didn't see any small plastic shims. Thanks for the reply though... I am used to jetting keihn fcr mx carbs...
This thread was helpful to read. I'm looking at doing the same thing on my 03 short track viper. The piston wash looks right on, but that was riding at 30 degrees (elevation 11-1200) and I'm afraid if the temp drops to zero I'll be too lean. I'm surprised though, because I've heard about stock viper jetting being plenty rich. It seems stupid to have to go to a bigger main jet for a stock motor in normal operating conditions, so I'm thinking I should raise the needles 1/2 and see. Carbs were cleaned the end of September, and it runs great as it is now.