Carb Stuff - 1999 KTM 300EXC
Don't ask me what the differences are between these two
needle sets....I don't know.  But supposedly they are
equivalent needles.  Why some bikes get the NOZ's and others
get the N85's is one of those great mysteries of life with KTM's.

N85A = NOZE    ---> Richest
N85B = NOZF
N85C = NOZG
N85D = NOZH
N85E = NOZI     ---> Leanest


I run the N85D in my 300EXC, which is about right.  It came
set up with a N85C, which was too rich.  My bike was
delivered with a set of jets and the leaner N85D needle, which
was kind of cool.

And while we're on the subject of carb tuning, there has been
much discussion about changing to a leaner slide.  The Keihn
carb comes with a #6 slide, which may be on the rich side.  
Many KTM owners have switched to a #7 slide, but I have
resisted.  While I was using the stock exhaust, I was tempted,
but after I replaced the stock exhaust with an FMF pipe/spark
arrestor combo, I didn't see the need.  The FMF Turbine Core
is shorter than the stock spark arrestor, and it seems like it is
more free-flowing and doesn't get such a buildup of spooge.  
Here's what I'm running with the FMF exhaust:

#6 slide, 172 main, 42 pilot, N85D with clip in #2 position
from the top, air screw a couple of turns out.

Here's what some guys were running with the #7 slide and
stock exhaust (for the most part):

#7 slide, 175 main, 45 pilot, N85C with clip in #2 position
from the top, air screw 1 3/4 turns out.

Either one probably works fine, but the #7 slide costs about
$60.  I'll stick with what I've got.