Jetting specs on a 2013KTM 250SX

The best place to start is with the jetting specs in the manual. That matrix provides elevation and temperature guidance adn will work very well. I have 2013 300 and that is where i got all my info

Don't quote me please, but I had read the hot setup is the suzuki needle I think?

they come stock rich on the needle (1st taper) and lean on the main. the stock needle actually works great if youre an aggressive track rider. my preference has changed a little as ive gotten faster and, dare i say, the rich 1st taper of the stock needles feels better than the NEC/NED needles @ the track... the stock needles also have a very short straight section so you are on the 1st taper almost immediately which is why the stock needle will load up if youre not aggressive. heres a couple posts of mine a few months back on the needle info. lots of guys are using the NED and NEC needles.

http://www.vitalmx.com/forums/Moto-Related,20/2013-KTM-250-SX,1241842?p…

on a side note NOZ needles are the same as the stock N1E needles but are a half clip leaner. the NED needles are the same as the NOZ needles with a leaner first taper. the NEC needles are the same as the NED needles but half a clip leaner. meaning if you are trying to keep all needles equal you would need to run them like so. ive noticed my 250sx is sensitive to 0.5 clip changes so its good to keep all this info in mind. ktmtalks got a ton of good info on needles for these bikes.


rich taper-----rich taper-------leaner taper----leaner taper
N1E clip 3 = NOZ clip 3.5 = NED clip 3.5 = NEC clip 4

you need to keep that in mind when making needle changes. i agree that the 158 and 160 mains dont seem to work very well. compound that with the fact that the '13 250sx jetting is based around 1640' elevation @ 68f with a mix ratio of 60:1. if you run a more normal ratio of 32:1 you need to richen jetting ~1.5%, and if you run closer to sea level or colder temps you need to richen even more. looking at the KTM manual also shows that for sand riding they want a 175 main jet. i dont know about you guys, but i dont think ive ever seen a *7* size main jet increase recommendation. if it takes that much fuel to run properly in the sand, i think running the stock 158 main is just asking for trouble anywhere else besides trail riding. JMO.

i posted a breakdown of the N1E/NOZ/NEC/NED needle series couple posts back. the NEC series and the stock N1E series are the same needle EXCEPT the NEC uses a leaner first taper *AND* the NEC is 1 full clip position leaner than the N1E series needle. so if you just want the leaner first taper feel and like the rest of the bikes response you'd run the NEC in clip 4, this would be EQUAL to the stock N1E in the 3rd clip. the same applies to the NED series needle, EXCEPT it is only 0.5 clip position leaner than the stock needle.

people like the NEC/NED needles because of the leaner first taper compared to the stock N1E series, this is why the sx runs really rich at ~1/4ish throttle. the stock needle works pretty good if youre a very fast and aggressive rider in the corners where youre not on the first taper very often, unfortunately im not the fastest guy at the track lol.

the last letter in each series needle is the straight length's diameter. for example from rich to lean it would go NECH - NECW - NECJ - NECK and so on. this series uses the letter "W" in place of " I "

for what its worth, id start with an NECW in clip 4. same straight length diameter as stock/ same 2nd/3rd tapers, just a leaner first taper, this will give you a good idea if you want to keep heading in this direction. if you do, i highly recommend you get the half clip versions too. i never saw a needle for them until i got this SX, its more picky than my honda. visit the KTMtalk forums too, my info comes from JerseyDevil over there, he's got the needle info down.

DIGGER: thanks man, just trying to get an idea on your situation vs mine here due to what i experience with my SX. like you, that thing pinged bad on a 162 under WOT, less on the 165. will skip straight to 170 (we just dropped literally 25 degress so i may even skip straight to the 175 instead) and retry, i think youve got it sorted man.

Try the stock pilot, Suzuki RM250 needle NECJ on the 3rd setting & a 172-175 main jet & your bike will thank you :-) I raced in Maine today & it was around 43-48 degrees out & my bike actually pinged & it hasn't pinged since the 1st day I rode it. I put the clip on the 4th setting & she was ripping & rewarded me with both holeshots :-) I love blowing all of buddy's trick 450s away on a weekly basis ,LOVE it :-)

Yeah the guys down here are running Suzuki needle and a bigger main, 180 and 185s...

I don't have the suzuki needle at the moment but switched stock needles and went way up on the main (172).

This a spec right from Factory Ktm we use it in all are bikes and it works great !!

Needle 1469G needle position 3rd clip ( SX 125 needle part # 54731034300)
40 pilot jet
170 main jet

What have you found that works best in the 2013 300 XC?

This will work great in the XC 300 also !!!

Needle 1469G needle position 3rd clip ( SX 125 needle part # 54731034300)
40 pilot jet
170 main jet

hey guys, first post! i know im a bit late too the party here :/ sorry! Im also running a 2013 250sx and im in Australia, my riding elevation is about 50m - 400m (160- 1500ft) and temp from 25-15C (77- 60F) just wondering if this these settings would be applicable to me as im having trouble with my jetting... running 40:1 motorex with a fmf fatty/titanium system
thanks everyone

Hi,
There's a guy here in NZ who has countless hours of 250sx dyno testing. He tuned Kayne Lamont's, Hamish Harwood's and Hamish Dobbyn's bikes - they all raced the aus mx series.
Anyway he swears by the JD jet kit (if $ are no prob he has a bigger carb mod) and he also has a powervalve spring mod for a better power curve. (suspension tech - if you want to find him on the web).
He's tested the suzuki needle etc but reckons for the NZ and Aus conditions the JD kit is better.

thanks i had a look at one! think i might get one. how accurate are they? yeah $$ is an issue, I'm 16 so i don't have a lot of money to be throwing around, getting suspension done and stuff at the moment so that's not going to be cheap