ive just done a full engine rebuild and after a few rides thought it was running a bit lean it was overheating blowing out coolant and pinking. so i pulled out the carb as1 and found a 170 main jet, 40 pilot, n1ef needle on top clip, air screw 3 turns. so ive put it back to the standard 42 pilot, 175 main, n1ef #2 and air screw 2 3/4 turns. and i find that it is to rich from around 1/8 throttle all the way to wot. i understand 2 3/4 turns is to far out should be between 1 and 2 for best results so going to drop back down to 40 pilot. but for the top end was thinking of running a different needle either a n3ch or nedj do you think they will be suitable with the current jets? will be used in-between 50-2000ft
ec 300 2012 jetting (needles)
- Thread starter sheepy
- Start date
float height has been set to 10mm couldn't bring myself to go to 16mm can see how any fuel would get in if set that low. the float is about 10 degrees from parallel with the carb body. am i right in thinking that the NEDJ will give a more smoother power delivery as the N3CH will give you more off a kick in the mid range. how do these needles respond to the mapping switch?
(F5)
Gold Level Site Supporter
Surely you have an AS2 carb with screws holding the cap on? Think they came in from 10 on or there about. 3 mates 2010, 13, 15 all changed to the RM needle suggested and transformed their bikes. I've ridden 2 of them and they are as close as I'd ever bother trying for. And give good mileage as a side benefit.
Jakobi
Super Moderator
The N3CH you'll want to run a size or two larger on the main. Usually 175-180ish, and a 38-40 pilot. Around clip 3.
The Suzuki NEDJ you'll probably end up with a 42 pilot and a 172-175 main. Needle in Clip 2 or 3.
Both needles come in half clip variations if required as well.
For your bike I'd keep your jets as is and simply drop the NEDJ in position 2. Then back the idle screw out as it's likely to race a bit with much less fuel being delivered at idle.
The Suzuki NEDJ you'll probably end up with a 42 pilot and a 172-175 main. Needle in Clip 2 or 3.
Both needles come in half clip variations if required as well.
For your bike I'd keep your jets as is and simply drop the NEDJ in position 2. Then back the idle screw out as it's likely to race a bit with much less fuel being delivered at idle.
So today I replaced the leaking float needle with one from a 2014 model it was 18mm long and old one 15mm thought this was odd as same carb maybe mine had One from an as1? But after a bit of bending I got the float hight to 10mm and while I had the carb apart dropped down to a 40 pilot jet readjusted the air screw now 2 turns out. This has seemed to clean up the whole range no more burble at 3/4 throttle. Still a little rich but a lot better and there is more of a kick to it in the lower revs found that it actually sometimes breaks the traction when going up a technical section. Guess the Suzuki needle will make it more liniear and KTM needle more of a kick?
750ft 15c in sunshine mode
750ft 15c in sunshine mode
Jakobi
Super Moderator
The stock N1EF has a very short straight section, which is also overly rich. It then tapers off quickly. You usually end up with nice off idle and a lean hole in the middle, or a fluffy bottom that snaps to life as it clears out.
Both the Suzuki and Yamaha/Ktm needle has a longer straight section which really helps to dial in the idle and off idle. The Suzuki is probably a bit leaner feeling off idle, and has much less taper through its profile. Steady supply of fuel. The Yamaha/Ktm is a dual taper and you really do feel the transition between the two. It almost leaves a small lean area in the middle/upper rpm where the engine transfers onto the pipe. You end up with a smooth grunty bottom end, and a wild top end on the pipe, with a strong transition between the two.
Both the Suzuki and Yamaha/Ktm needle has a longer straight section which really helps to dial in the idle and off idle. The Suzuki is probably a bit leaner feeling off idle, and has much less taper through its profile. Steady supply of fuel. The Yamaha/Ktm is a dual taper and you really do feel the transition between the two. It almost leaves a small lean area in the middle/upper rpm where the engine transfers onto the pipe. You end up with a smooth grunty bottom end, and a wild top end on the pipe, with a strong transition between the two.
If there was such a position of Sommelier of 2 stroke carb needles Jakobi I think you would own it!
Jakobi
Super Moderator
My knowledge is limited as. I only really know the ones I've played with.. Pretty small scope in the big picture I'm sure!!
Well I got the n3ch needle today so it?s in the bike and what a difference haven?t rode it yet because of there being to many people around but just of the bench it sounds a lot different a lot smoother idle had to wind the idle screw back about 2 turns. Overall it sounds a lot cleaner. Im going out on it tonight so will update this post but it seems like a totally different bike. Current setup
N3ch #3
178 main
40 pilot
1 1/2 air screw
735ft
15.2c
N3ch #3
178 main
40 pilot
1 1/2 air screw
735ft
15.2c
The bike is totally different with this needle pleanty of grunt in the bottom end and nice to ride and then get on the pipe and wow front end up on ever straight going past loads of bike on the pipe in the hare and hound even had someone ask me what I had done to it to make a gasser sing like that I think the should come out the factory like this. Removed the plug and a lovely brown colour I am really impressed with this bike now
