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.
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.