Cud use some help jetting an 03 300
- Thread starter gasgasxc
- Start date
thumperflipper
New member
I'm pretty good at jetting but have been beating my head against a wall for 3 years with my bike (07 EC300). Finally bought the JD Jetting kit and I wish I had done it three years ago. My bike was always rich. I installed the leanest JD needle, clip at top, better but still rich. A phone call to them after install and they sent me a third needle. My bike rips now, and my pipe is CLEAN, I mean NO spooge at all. I couldn't be happier
https://www.youtube.com/watch?v=4FquiOs6FFo
https://www.youtube.com/watch?v=4FquiOs6FFo
Jakobi
Super Moderator
I haven't read the whole thread yet (I will).
What number slide?
Have you set the float height?
Mechanical condition of the bike ok?
I have no experience on the earlier engines, but from all accounts they (in combination with the AS1 carb) require more fuel off the bottom. I would start with an F/G diameter needle (either NE series / N3 series, probably the later).
Another consideration, if the carb has a lot of hours on it. The nozzle is a non replacable part which can wear through use. This can result in more clearance between the straight section and the nozzle. You can work around it a bit with leaner settings, but I'd start richer and work down.
What number slide?
Have you set the float height?
Mechanical condition of the bike ok?
I have no experience on the earlier engines, but from all accounts they (in combination with the AS1 carb) require more fuel off the bottom. I would start with an F/G diameter needle (either NE series / N3 series, probably the later).
Another consideration, if the carb has a lot of hours on it. The nozzle is a non replacable part which can wear through use. This can result in more clearance between the straight section and the nozzle. You can work around it a bit with leaner settings, but I'd start richer and work down.
Will order the n3cj ktm needle and the n1eg needle on Monday and hopefully get this baby straightened out.Appreciate the ideas on this one, do not wanna keep taking this carb in and out.
Another thing, the bike has two m?tal inserts, one in between the carb and intake.And one sits in the carb on th? airboot side.Must be some kinda fancy fuel directioning devices.Or as I like to say, more crap you dont need.Throw aways? Gotta have it? Give to friend with gas gas?
Do they affect jetting at all.
Another thing, the bike has two m?tal inserts, one in between the carb and intake.And one sits in the carb on th? airboot side.Must be some kinda fancy fuel directioning devices.Or as I like to say, more crap you dont need.Throw aways? Gotta have it? Give to friend with gas gas?
Do they affect jetting at all.
Jakobi
Super Moderator
I'd almost put $5 on the J being significantly too lean. The J feels too lean in my 2013 250 with an AS2.
If you wanted to step it down for a leaner option I would consider the following.
Ditch the N1EG - the straight section on this needles profile is so short it has very limited effect. The issue revolves around the 1st taper supplying too much fuel. The straight is so short, in many cases people crank the idle up and lift the slide to the point that they are trying to match the idle and pilot against the taper. This results in inconsistancy as minor adjustments to the idle speed then through everything else out. Another variable to deal with.
I'd order an N3EG, and N3CH (or N3CW). This gives you a half clip leaner profile, and 2 different diameters to work with. If you went G and H you'd also be able to run with the same pilot and air screw adjustments only for testing purposes, and both needles will run on the same main. Means you only need to lift the tank/rotate the carb to access the needle, as opposed to pulling the whole carb.
If you wanted to step it down for a leaner option I would consider the following.
Ditch the N1EG - the straight section on this needles profile is so short it has very limited effect. The issue revolves around the 1st taper supplying too much fuel. The straight is so short, in many cases people crank the idle up and lift the slide to the point that they are trying to match the idle and pilot against the taper. This results in inconsistancy as minor adjustments to the idle speed then through everything else out. Another variable to deal with.
I'd order an N3EG, and N3CH (or N3CW). This gives you a half clip leaner profile, and 2 different diameters to work with. If you went G and H you'd also be able to run with the same pilot and air screw adjustments only for testing purposes, and both needles will run on the same main. Means you only need to lift the tank/rotate the carb to access the needle, as opposed to pulling the whole carb.
I have just gone to the n3cj 42 178 I runs amazing, looked at the plug not really sure if it's lean or just clean I might drop it a clip and have another look would a larger main make it safer?
I went from position #3 to #4 and I didn't like I the feel of it, deeper sound and loud induction noise from the airbox
I really liked it in pos3 but got me worries about running it too lean, I really like the kick of the n3cj, how to get it running safe? I.e richer larger main?
I really liked it in pos3 but got me worries about running it too lean, I really like the kick of the n3cj, how to get it running safe? I.e richer larger main?
Jakobi
Super Moderator
The diameter is only the thickness of the straight section. It only effects the off idle to maybe 1/4 throttle at most. Then its all taper profile and clip position, and overlaps with main towards WOT.
Lean diameter probably won't cause any immediate dangers, but the bike will feel flat and less torquey and require more downshifts to keep it in the mid range where its making power. It'll also run a bit hotter both due to being lean, and also the added clutch abuse to compensate.
Lean diameter probably won't cause any immediate dangers, but the bike will feel flat and less torquey and require more downshifts to keep it in the mid range where its making power. It'll also run a bit hotter both due to being lean, and also the added clutch abuse to compensate.
gassergrant
New member
I had this problem I used the n3eg ktm needle on a 38 slow and a 180 main it's transformed the bike to something that works well
Right on.
After listening to what you guys think ,we ordered the n3cj and the n3eg.We are staying clear of the n1 needles, although one of you had some success with the n1ef.
We can change the needles without pulling the tank.Im hoping this is the cure.Thanx again for the input.
After listening to what you guys think ,we ordered the n3cj and the n3eg.We are staying clear of the n1 needles, although one of you had some success with the n1ef.
We can change the needles without pulling the tank.Im hoping this is the cure.Thanx again for the input.
firffighter
New member
Jetting is very subjective. NW is unique as you well know, and riding TSF is even more of a unique experience that is hard to compare to other terrains, elevation changes, temps and humidity.
My brother has an '03 EC250 and he has been tweaking with his jetting for 6 years of ownership looking for that combination of linear delivery without being boggy or too crisp. A fine line, I know. I rode his bike this winter and it's so spot on now. Great for tackling Oregon nasties.
CEK Sudco needle #3
#8 slide (huge difference in off idle performance)
40 pilot
178 main
I'm running virtually the same jetting (42 pilot) on my '03 KTM 300 with same results. Linear delivery throughout, no hesitation or boggy feel at all.
My brother has an '03 EC250 and he has been tweaking with his jetting for 6 years of ownership looking for that combination of linear delivery without being boggy or too crisp. A fine line, I know. I rode his bike this winter and it's so spot on now. Great for tackling Oregon nasties.
CEK Sudco needle #3
#8 slide (huge difference in off idle performance)
40 pilot
178 main
I'm running virtually the same jetting (42 pilot) on my '03 KTM 300 with same results. Linear delivery throughout, no hesitation or boggy feel at all.
Jacob 'Berg
Member
+1 on the CEK. My 300 runs well with that needle.
