difference between N3CH and NECH?
- Thread starter ggmaniac
- Start date
The starting H diameter is the same so they will both require the same sized pilot. Not sure if the straight section lengths are the same or not but from there they're significantly different. The N3xx needles are 2 taper, the NExx needles are 3 taper I believe.
Below is a description by Jakobi when I asked a similar question a while back:
The lengths are pretty similar with the NEDx vs the N3Ex. x being the diameter on the straight section. All the diameters are the same across the OEM needles. The main differences in them are the taper profiles, and thats the reason why I don't think you'll ever find the grunt you are looking for with the NEDx (even with a larger diameter).
N1Ex (3 tapers) Wayy rich -> Moderate -> rich - Everyone lifts the clip position to try and overcome the rich first taper, this leaves the bike lean in the middle, the last taper provides good fuel and likes to be paired with a smaller main.
N3Ex (2 taper) Rich -> Lean - With the right diameter you can get good torquey response off the bottom with a wickid hit/transition in the mid range when it leans off abruptly. Some issues experienced that to get the bottom lean enough to be crisp you can fall too lean in the mid range. Being that there is no 3rd taper you need to use a largish main to supply extra fuel towards WOT.
NEDx (3 tapers) Lean -> Moderate -> Rich - The nature of the beast, starts lean and progressively gets richer. It means you can have good clean throttle response with no surprises in the rev range. The clean bottom end lacks torque in some applications, but also responds really well to clutch. Richish mid range smooths the hit, and the needle supplies good fuel towards WOT. Smallish main compared to N3 (same as N1Ex).
JD Needles (3 tapers) Rich -> Moderate -> Lean - Good torquey delivery off the bottom, enough fuel to be smoothish but strong in the mid range, lean towards WOT asks for a big main jet. Obviously some significant differences between red and blue. Red is more comparable to a cross between N3xx and NEDxx.
Below is a description by Jakobi when I asked a similar question a while back:
The lengths are pretty similar with the NEDx vs the N3Ex. x being the diameter on the straight section. All the diameters are the same across the OEM needles. The main differences in them are the taper profiles, and thats the reason why I don't think you'll ever find the grunt you are looking for with the NEDx (even with a larger diameter).
N1Ex (3 tapers) Wayy rich -> Moderate -> rich - Everyone lifts the clip position to try and overcome the rich first taper, this leaves the bike lean in the middle, the last taper provides good fuel and likes to be paired with a smaller main.
N3Ex (2 taper) Rich -> Lean - With the right diameter you can get good torquey response off the bottom with a wickid hit/transition in the mid range when it leans off abruptly. Some issues experienced that to get the bottom lean enough to be crisp you can fall too lean in the mid range. Being that there is no 3rd taper you need to use a largish main to supply extra fuel towards WOT.
NEDx (3 tapers) Lean -> Moderate -> Rich - The nature of the beast, starts lean and progressively gets richer. It means you can have good clean throttle response with no surprises in the rev range. The clean bottom end lacks torque in some applications, but also responds really well to clutch. Richish mid range smooths the hit, and the needle supplies good fuel towards WOT. Smallish main compared to N3 (same as N1Ex).
JD Needles (3 tapers) Rich -> Moderate -> Lean - Good torquey delivery off the bottom, enough fuel to be smoothish but strong in the mid range, lean towards WOT asks for a big main jet. Obviously some significant differences between red and blue. Red is more comparable to a cross between N3xx and NEDxx.
Jakobi
Super Moderator
Nice copy/paste Nath 
I'm glad someone else took the time to answer this. I wasn't looking forward to all the typing again.
I have a few blurbs saved in text docs. I know I've said it before, but I really should do a sticky with all the dribbs and drabs of info that I've put into threads and PMs.
Markus,
Generally clip for clip, you'll want to run the N3Ex needle one clip position richer than you would the stock N1Ex, or the Suzuki NEDx so in that case you could say the N3xx needle is a bit leaner than the NExx needle. An N8Rx uses the same taper profile as the N3Cx and is a full clip richer.
There is actually a whole range of needles that share the same taper profile as the N3xx.
In 1/2 clip variations from leanest to richest they are...
N89x=leanest
N3Cx
N3Ex
N8Rx
N2Zx
N4Dx
N3Vx
N4Ax
N6Mx=richest
Nxxx needle diameters
D=2.685mm
E=2.695mm (JD Blue)
F=2.705mm
G= 2.715
H= 2.725
W/I=2.735 (JD Red)
J= 2.745
K=2.755
Generally for the 2010+ models which have shipped with the 38mm PWK AS2 (flat cap stamped 38 on top, and shallow bowl) a 300cc engine will respond well to a J diameter needle, a 250 likes a W/I (depending on needle), and a 200 will take a H. However in saying that its being picky and by shuffling pilots you can still get a H to work in a 300. Richer will be a bit torquier. All these were tested in Australian conditions with our fuels (98RON) and temps between 15-35C.
If you find you have an AS1 (round threaded cap) most report the JD Blue as the best needle for the job. If you have a 36mm AS2...
I'm glad someone else took the time to answer this. I wasn't looking forward to all the typing again. I have a few blurbs saved in text docs. I know I've said it before, but I really should do a sticky with all the dribbs and drabs of info that I've put into threads and PMs.
Markus,
Generally clip for clip, you'll want to run the N3Ex needle one clip position richer than you would the stock N1Ex, or the Suzuki NEDx so in that case you could say the N3xx needle is a bit leaner than the NExx needle. An N8Rx uses the same taper profile as the N3Cx and is a full clip richer.
There is actually a whole range of needles that share the same taper profile as the N3xx.
In 1/2 clip variations from leanest to richest they are...
N89x=leanest
N3Cx
N3Ex
N8Rx
N2Zx
N4Dx
N3Vx
N4Ax
N6Mx=richest
Nxxx needle diameters
D=2.685mm
E=2.695mm (JD Blue)
F=2.705mm
G= 2.715
H= 2.725
W/I=2.735 (JD Red)
J= 2.745
K=2.755
Generally for the 2010+ models which have shipped with the 38mm PWK AS2 (flat cap stamped 38 on top, and shallow bowl) a 300cc engine will respond well to a J diameter needle, a 250 likes a W/I (depending on needle), and a 200 will take a H. However in saying that its being picky and by shuffling pilots you can still get a H to work in a 300. Richer will be a bit torquier. All these were tested in Australian conditions with our fuels (98RON) and temps between 15-35C.
If you find you have an AS1 (round threaded cap) most report the JD Blue as the best needle for the job. If you have a 36mm AS2...
My 36mm kitted 300 hated the leaner diameters so I/W (JD Red) and onwards. Even with the appropriate pilot it lacked torque and the clutch had to be abused far too much to get it to make any decent power off idle.
The JD Blue was a good needle, was nice and torquey off the bottom and delivered a nice linear power. Only problem with the blue needle is i could never get great economy. Was ok but never great. I never tried a H diameter needle in the carb but I reckon that would have been the perfect one.
If you have an oval bore 36mm like I now do they like a diameter in between what the 36mm and 38mm carbs like and similarly seem to take jets in between as well. My bike now loves the I/W diameter needle.
The JD Blue was a good needle, was nice and torquey off the bottom and delivered a nice linear power. Only problem with the blue needle is i could never get great economy. Was ok but never great. I never tried a H diameter needle in the carb but I reckon that would have been the perfect one.
If you have an oval bore 36mm like I now do they like a diameter in between what the 36mm and 38mm carbs like and similarly seem to take jets in between as well. My bike now loves the I/W diameter needle.
GMP
Active member
Funny this comes up. So I decide to race the '07 bike this weekend, as its a nasty rock ride and this bike is dialed for that, and my '12 a bit over sprung at the moment. Being I robbed the JD Blue needle for the '12, figured I might as well try some of the rich diameter NEDx /NECx I had ordered and waited awhile for, but never tried. Put the NEDF #3 in with a 45 pilot and 178 main. Wow, this needle is not lean and flat off the bottom like the H dia. The torque is back. Pulls strong and smooth off idle with a smoother hit. Maybe a hair rich in the lower mid so I'll try the NECF#3 tomorrow. Glad I ordered these now.
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Jakobi
Super Moderator
Thats a positive review Glenn. Glad to hear its working for you. The NExx needles and the N3xx both have a decent length on the straight section before they head into the taper profile. The stock N1Ex or NOZx are so short. If you ever get them side by side you'll see what I mean.
GMP
Active member
Yes I know, last time I ran the N1Ex needles was on a stock '00 250 when I first got it. I have a lot of them as a few came with each new GG. These F dia (and maybe G) have promise in the older carbs based on my limited test. Sat before the race I'll go out locally with NEDF,NECF,NEDG,NECG and pick a winner. These are not typically stocked, as they are the rich dia edge of the range and not the standards, but are available. Real nice thing about the old carb is its easy to swap needles on the trail with a slight rotation, I don't even have to remove the fuel line. Also seems a lot less fussy in general.
Hi,
thanks for your fast and helpful posts.
Actually I am running a NECH (on an 38ASII carb) as the NEDJ seemed to be a little lean to me. After climbing slow some steep hills it needed some time to rev down to idle speed.
Thought about trying the N3CH but after reading this posts I won?t try (don?t like a hard transition in the mid)
cheers from germany
Markus
thanks for your fast and helpful posts.
Actually I am running a NECH (on an 38ASII carb) as the NEDJ seemed to be a little lean to me. After climbing slow some steep hills it needed some time to rev down to idle speed.
Thought about trying the N3CH but after reading this posts I won?t try (don?t like a hard transition in the mid)
cheers from germany
Markus
