What needle groove is everyone using with their full pipe (not slip on) and filter mods, foam or K&N? Just curious. [img]i/expressions/face-icon-small-smile.gif[/img] According to Alba (the full pipe i have) its 5th groove from top for me. Seems ok. Thought I might try 4th and see if it makes a difference. Got a tannish color on the spark plug so mixture seems ok. TIA

 

6 views and nobody wants to say what groove they are running?

 

We're running fourth spot here at 5000ft and it helps. I hear it helps even more at sea level. The 5th spot seems kind of over-kill.

 

Overkill is what i'm thinking also. Thanks for the comment.

 

What fuction does the needle position serve? I have read different people in here, with the same mods use a different number with the same elevation. I know first hand that it makes a big difference on a ds650. Thanks.

 

The needle serves 1/4 to 3/4 throttle...I run on the forth clip Dynojet kit.

 

Your needle is for 1/4-3/4 throttle. Mains are for top end and pilots for just off idle. Of course all these jets over-lap into the next area of rpm then sign off and have no impact at all.

 

So raising or lowering the needle makes the fuel ratio rich or lean? Thanks

 

Raising the needles richens it up (hence lowering the clip)....