15 ktm250sx help jetting!?!

Benh250
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8/10/2014 7:03pm Edited Date/Time 10/1/2014 8:41pm
I just changed my jetting to the Suzuki needle NECJ 3# 40 pilot 175 main, 50/50 race gas premix 40.1 927. So my problem is that it is pinging on deceleration?
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Markee
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8/11/2014 5:45am
Try 100% race fuel. I use CAM2 110 40:1, Never had a problem
Digger29
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8/11/2014 6:42am
Try a 42 pilot and then go the 4th down setting on the clip. Some guys are having better luck this way.
MxKing809
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8/11/2014 10:25am
Yup, I have to run the 4th clip here in Michigan
Kenman
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8/12/2014 5:12pm
Digger29 wrote:
Try a 42 pilot and then go the 4th down setting on the clip. Some guys are having better luck this way.
Can you shoot me an email digger! I have a 2013 250 brand new. Need some setup advice! Suttonkf@gmail.com

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motoray
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8/12/2014 10:49pm
i just switched to 4th clip today and made a huge difference.
digger
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8/14/2014 10:30am Edited Date/Time 8/14/2014 10:33am
I setup a bunch of these bikes for local riders in our club, and that "J" needle usually winds up being to lean. I settup 300's using the "J" needle. When jetting 250's I use an NECW #3 needle which is the next richer needle with a 38 pilot and 172 main. The Suzuki needles have a very rich 3rd taper so they don't require a large main jet.
Tuck812
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8/17/2014 1:52pm
Hi guys what's the best jetting for a stock carb pro circuit pipe and shorty silencer?
Digger29
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8/19/2014 5:59am
I ran the stock pilot and the NECJ needle on the 3rd setting and a 175 main jet on my 13 250SX with the stock 36 carb and it ran amazing from the bottom right to the top. I was and still run straight race Sunoco Supreme race gas at 32:1 and I know this could definitely make a difference in the jetting but these settings have worked for just about everyone I spoken to with a 250SX or TC250. Some guys are running a 172 main and a few are a 178. I did run a 178 for a time but it was just a touch rich so I settled on the 175 and have been running this same combo since a month after I got my 13 in the summer of 12.
KHenry901
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8/28/2014 7:02pm
Digger29 wrote:
I ran the stock pilot and the NECJ needle on the 3rd setting and a 175 main jet on my 13 250SX with the stock 36...
I ran the stock pilot and the NECJ needle on the 3rd setting and a 175 main jet on my 13 250SX with the stock 36 carb and it ran amazing from the bottom right to the top. I was and still run straight race Sunoco Supreme race gas at 32:1 and I know this could definitely make a difference in the jetting but these settings have worked for just about everyone I spoken to with a 250SX or TC250. Some guys are running a 172 main and a few are a 178. I did run a 178 for a time but it was just a touch rich so I settled on the 175 and have been running this same combo since a month after I got my 13 in the summer of 12.
Quick question, I was told the same set up. 40 pj, 178 main. But the needle is different. I have a N8RE. Has anyone tried this Needle?
digger
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8/28/2014 9:15pm
KHenry901 wrote:
Quick question, I was told the same set up. 40 pj, 178 main. But the needle is different. I have a N8RE. Has anyone tried this...
Quick question, I was told the same set up. 40 pj, 178 main. But the needle is different. I have a N8RE. Has anyone tried this Needle?
That is a very rich duel taper needle for a 250. It is Similar in taper profile to the oem needle that is used in current yz250's, but much richer in diameter and L-1. IMO, that needle is to rich for your 250, also that 40 pilot jet, when used with that N8RE needle is to lean. The main looks about right though.
KHenry901
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8/29/2014 3:57am
KHenry901 wrote:
Quick question, I was told the same set up. 40 pj, 178 main. But the needle is different. I have a N8RE. Has anyone tried this...
Quick question, I was told the same set up. 40 pj, 178 main. But the needle is different. I have a N8RE. Has anyone tried this Needle?
digger wrote:
That is a very rich duel taper needle for a 250. It is Similar in taper profile to the oem needle that is used in current...
That is a very rich duel taper needle for a 250. It is Similar in taper profile to the oem needle that is used in current yz250's, but much richer in diameter and L-1. IMO, that needle is to rich for your 250, also that 40 pilot jet, when used with that N8RE needle is to lean. The main looks about right though.
Awesome, thank you. I got that info from some Ktm guys that are more into off road. Would you still recommend the NECJ for a fast A rider? I noticed you let a couple faster guys ride yours a while back.

Again, thank you for the help
digger
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8/29/2014 10:01am
KHenry901 wrote:
Quick question, I was told the same set up. 40 pj, 178 main. But the needle is different. I have a N8RE. Has anyone tried this...
Quick question, I was told the same set up. 40 pj, 178 main. But the needle is different. I have a N8RE. Has anyone tried this Needle?
digger wrote:
That is a very rich duel taper needle for a 250. It is Similar in taper profile to the oem needle that is used in current...
That is a very rich duel taper needle for a 250. It is Similar in taper profile to the oem needle that is used in current yz250's, but much richer in diameter and L-1. IMO, that needle is to rich for your 250, also that 40 pilot jet, when used with that N8RE needle is to lean. The main looks about right though.
KHenry901 wrote:
Awesome, thank you. I got that info from some Ktm guys that are more into off road. Would you still recommend the NECJ for a fast...
Awesome, thank you. I got that info from some Ktm guys that are more into off road. Would you still recommend the NECJ for a fast A rider? I noticed you let a couple faster guys ride yours a while back.

Again, thank you for the help
The Suzuki NECJ combo is a good proven combo for mx or offroad, novice to expert.

Lately I have started to refine the 250 jetting a little more,and have been using a triple taper Kawasaki/Suzuki needle with a little leaner 1st taper than the Suzuki NExx series needles, and really like it. The setup is N3WK needle #4 ,http://www.partzilla.com/parts/detail/suzuki/SP-13383-37EQ0.html a 40 pilot and 175 main
Digger29
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8/29/2014 11:56am
digger wrote:
That is a very rich duel taper needle for a 250. It is Similar in taper profile to the oem needle that is used in current...
That is a very rich duel taper needle for a 250. It is Similar in taper profile to the oem needle that is used in current yz250's, but much richer in diameter and L-1. IMO, that needle is to rich for your 250, also that 40 pilot jet, when used with that N8RE needle is to lean. The main looks about right though.
KHenry901 wrote:
Awesome, thank you. I got that info from some Ktm guys that are more into off road. Would you still recommend the NECJ for a fast...
Awesome, thank you. I got that info from some Ktm guys that are more into off road. Would you still recommend the NECJ for a fast A rider? I noticed you let a couple faster guys ride yours a while back.

Again, thank you for the help
digger wrote:
The Suzuki NECJ combo is a good proven combo for mx or offroad, novice to expert. Lately I have started to refine the 250 jetting a...
The Suzuki NECJ combo is a good proven combo for mx or offroad, novice to expert.

Lately I have started to refine the 250 jetting a little more,and have been using a triple taper Kawasaki/Suzuki needle with a little leaner 1st taper than the Suzuki NExx series needles, and really like it. The setup is N3WK needle #4 ,http://www.partzilla.com/parts/detail/suzuki/SP-13383-37EQ0.html a 40 pilot and 175 main
Hey Digger, btw love the screen name :-) Say I tried the N3WK needle, what am I going feel differently?
Markee
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8/29/2014 1:03pm
I've been refining mine as well, but its a constant refining while folks seem to be looking for the magic setup which per manual needs to be adjusted every 18 degree temp swing and every 1000-1500 elevation change.

I have been taking the useless stock jets (155, 158 mains) and custom bores on the lathe :D

digger
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8/29/2014 4:01pm
Digger29 wrote:
Hey Digger, btw love the screen name :-) Say I tried the N3WK needle, what am I going feel differently?
I noticed your name a few years ago and thought I recognize that name. I'm a former drag racer who use to race a digger, which is another name for a dragster.

The N3WK is another triple taper Kawasaki/Suzuki needle that is similar in profile to Suzuki's NExx series. IMO, bike seems to run even cleaner off the bottom than the NECJ and then revs quicker, but smoothly throught the middle and into the same topend as the NECJ. It's a nice clean setup for guys that are using the stock slide. As an added bonus for 90% of those that are using the NExx needles already, I find that it is a direct replacement for that needle meaning, I leave the pilot and main the same as the NExx needle and just replace the needle and go.

You can buy the N3WK needle through either Kawasaki (99' kx250) or Suzuki(00' rm250) , but the needle is cheaper when bought through Suzuki for some reason.
http://www.partzilla.com/parts/detail/kawasaki/KP-16187-1079.html
http://www.partzilla.com/parts/detail/suzuki/SP-13383-37EQ0.html
Digger29
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8/30/2014 5:12am
Very interesting. Thanks for the info and for the $12 I'll definitely give one a try.
digger
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8/30/2014 4:17pm Edited Date/Time 8/30/2014 4:20pm
Digger29 wrote:
Very interesting. Thanks for the info and for the $12 I'll definitely give one a try.
I just realized you have a 300sx. The above jetting that I listed is specifically for use in 250's. For guys that want to try that Suzuki N3xx needle in their 300's,I would recommend that you use the 1/2 clip leaner N3YK in the #3 clip to startout. The 300's like to be jetted slightly leaner through the middle than the 250's.

250's= N3WK #4, 40 pilot, 175 main, and startout at 1.5 out on the air screw.

300's=N3YK #3, 40 pilot, 175 main, and air screw @ 1.5.

These are safe starting #'s for the sx. I have run the 250/300's xc and xc-w's with a 38/40 pilots and 168 mains safely.
KHenry901
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9/8/2014 6:15pm
Digger29 wrote:
Very interesting. Thanks for the info and for the $12 I'll definitely give one a try.
digger wrote:
I just realized you have a 300sx. The above jetting that I listed is specifically for use in 250's. For guys that want to try that...
I just realized you have a 300sx. The above jetting that I listed is specifically for use in 250's. For guys that want to try that Suzuki N3xx needle in their 300's,I would recommend that you use the 1/2 clip leaner N3YK in the #3 clip to startout. The 300's like to be jetted slightly leaner through the middle than the 250's.

250's= N3WK #4, 40 pilot, 175 main, and startout at 1.5 out on the air screw.

300's=N3YK #3, 40 pilot, 175 main, and air screw @ 1.5.

These are safe starting #'s for the sx. I have run the 250/300's xc and xc-w's with a 38/40 pilots and 168 mains safely.
I finally got this Needle for my 250. Revs so much quicker now and it's super smooth from bottom to top. I'll be out on the track this weekend.

Also the 15's pipes still crac. Mine lasted 5 hours.
Tuck812
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9/10/2014 11:58am
Digger29 wrote:
Very interesting. Thanks for the info and for the $12 I'll definitely give one a try.
digger wrote:
I just realized you have a 300sx. The above jetting that I listed is specifically for use in 250's. For guys that want to try that...
I just realized you have a 300sx. The above jetting that I listed is specifically for use in 250's. For guys that want to try that Suzuki N3xx needle in their 300's,I would recommend that you use the 1/2 clip leaner N3YK in the #3 clip to startout. The 300's like to be jetted slightly leaner through the middle than the 250's.

250's= N3WK #4, 40 pilot, 175 main, and startout at 1.5 out on the air screw.

300's=N3YK #3, 40 pilot, 175 main, and air screw @ 1.5.

These are safe starting #'s for the sx. I have run the 250/300's xc and xc-w's with a 38/40 pilots and 168 mains safely.
The n3wk needle is a hard one to find I got lucky and found one at a dealership in Covington,Louisiana everywhere else was out.
swtwtwtw
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9/12/2014 4:59am
How does the plug look with a 175 main. Mine is cocoa brown already with stock jetting. AM I missing something regarding the use of a larger main jet? thanks
Digger29
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9/12/2014 6:25am
My plug looks awesome with a 175. Yes, you are definitely missing something. Rev you bike wide open on the stand, it just warbles and won't rev wide open clean. It will cut out. Then put a 175 and rev it wide open. It will rev cleanly without warbling and cutting out with the 175 because it's getting fuel now. When I first got my 13 and was struggling getting the jetting correct I was told from a good friend who works for factory KTM in CA to put a 180 in it.
swtwtwtw
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9/12/2014 7:24am
Thanks d29. I will try it tomorrow at Comp Edge here in socal. I will give my observations too. And again thanks for sharing all your tech on these bikes. :-)
Digger29
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9/12/2014 10:42am
I just did the very same thing with a club members 14 250SX a cpl of Sundays ago at the track and he couldn't believe it either. The stock 158 main will not allow the bike to rev out. I walked over to my trailer and grabbed a 175 main jet and popped into his bike and the thing revved to the moon cleanly without any stumbling. I can't for the life of me figure out why KTM sends a 250SX out with a 158 main in it. All of my RM 250s all ran 172 mains and the 3yrs I raced CR250s they all had 175-178 mains and to me this is the correct area for a 250 2 stroke main jet-wise with a Keihin carb. Maybe the woods guys can run a 158-160 main jet but for MX you're going to need the bigger main jets to allow the bike to rev and make power up top.
swtwtwtw
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9/12/2014 4:45pm
Well, the change is made. while I was at it, i put the 40 pilot in and dropped the needle one notch. The bike a 2014 TC250 btw. I can hear a deeper exhaust sound when I fired her up, and yup it revs clean. But it did before, just a bit tingy sounding by comparison. I agree D29, i ran the jetting you mentioned on my 2003-2006 RM250 and CR250's.
For those interested, the suspension on this bike is flat out awesome, no I am not crazy, nor are the guys ( who have spent big bucks on their bikes suspension) after they ride this one. What I discovered was that it takes a good hour of initial riding with the clickers set very soft to break in and then adjust the clickers to balance. I have 6 hours now and the settings couldn't be better for where I ride. 25mm static sag, 1 3/4 turns out on high speed comp, 12 clicks out low speed comp and 10 out on the rebound. front, 12 comp, 10 rebound. I am using stock springs, and I weigh a fluctuating 175-185 throughout the year. I also run the bars in #3 forward position.
I am just chomping on the bit to get out in morning. Thanks for all who contribute.
swtwtwtw
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9/13/2014 6:55pm
well, running a 175 for my riding area, sucked. It was way too rich, and the loss of snap really made riding the track tough. Plug check revealed a dark, dark brown porcelain. The good thing is I know the stock jetting very well and can return to that . I put a 165 in for the next ride and see if the engine retains its character and gets some more rev, not that i wanted more though, I am curious. It sure is a pain to change jetting, as I have to partially remove the subframe to get access to the carb. Otherwise I would have done it at the track. Oh well, fun day riding nonetheless. :-)
swtwtwtw
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9/14/2014 1:32pm
ahhh, good today, same track, 97 degrees outside. A difference I felt was that the engine would get on the pipe in 3rd earlier. I am sure somebody who could really ride well would notice more. I had fun and I imagine that it will be even crisper at Glen Helen, as it is 1200 ft lower elevation. Now I really won't be able to hang on to it, haha.
snape99
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10/1/2014 8:41pm
Hi guys. What spark plug would be recommended for a 15 ktm 250sx. Ive been using NGK BR8ECM. I have been fouling quite a few of these on startup. Once running they are fine.
Cheers
Sug520
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11/22/2017 5:47am
digger wrote:
I setup a bunch of these bikes for local riders in our club, and that "J" needle usually winds up being to lean. I settup 300's...
I setup a bunch of these bikes for local riders in our club, and that "J" needle usually winds up being to lean. I settup 300's using the "J" needle. When jetting 250's I use an NECW #3 needle which is the next richer needle with a 38 pilot and 172 main. The Suzuki needles have a very rich 3rd taper so they don't require a large main jet.
What would you recommend for a 2012 KTM 250XC and a 2014 TC250. Both currently have stock jetting from the factory. I’m at sea level in Texas. Temps From 40-90 weather.

Jayklash
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8/23/2019 8:41am
Digger29 wrote:
Very interesting. Thanks for the info and for the $12 I'll definitely give one a try.
digger wrote:
I just realized you have a 300sx. The above jetting that I listed is specifically for use in 250's. For guys that want to try that...
I just realized you have a 300sx. The above jetting that I listed is specifically for use in 250's. For guys that want to try that Suzuki N3xx needle in their 300's,I would recommend that you use the 1/2 clip leaner N3YK in the #3 clip to startout. The 300's like to be jetted slightly leaner through the middle than the 250's.

250's= N3WK #4, 40 pilot, 175 main, and startout at 1.5 out on the air screw.

300's=N3YK #3, 40 pilot, 175 main, and air screw @ 1.5.

These are safe starting #'s for the sx. I have run the 250/300's xc and xc-w's with a 38/40 pilots and 168 mains safely.
Hi I followed your jetting advice for my 2014 KTM SX 250 and it ran amazing. Have you got any jetting specs for my 2018 KTM SX 150? Would really appreciate it
AJ565
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8/23/2019 9:46am
Jayklash wrote:
Hi I followed your jetting advice for my 2014 KTM SX 250 and it ran amazing. Have you got any jetting specs for my 2018 KTM...
Hi I followed your jetting advice for my 2014 KTM SX 250 and it ran amazing. Have you got any jetting specs for my 2018 KTM SX 150? Would really appreciate it

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