Ktm 300 xc jetting

[2smokeadam]

Bought a brand new left over 2013 ktm 300xc last year and ran it for a month last season . Ran ok but had a fair amount of sploige around the silencer with a mix of 50:1 ams oil full synthetic . Just cusious what you guys are running for jetting ??

[giantjoe]

There is an annual thread that pops up on this. Wait a couple months and see what there is for 2015... Here's the 2013 thread. viewtopic.php?f=3&t=9410&p=70937&hilit= ... ing#p70937" onclick="window.open(this.href);return false;

[malcolmzilla]

what i settled on for my 14 TE250

PJ 38
air screw ~ 1.5 turns out
N8RJ needle on 2nd from top
162 main
KTM carb heater

nice lean clean and torquey, the rare WFO run, it didn't seem to be short on fuel
never fouled a plug

with no changes to my jetting, 70:1 amsoil sabre mix eliminated the spooge

some say 50:1 will burn just fine if your jetting is spot on

[Dave8444]

Go buy a JD jet kit it fixed mine.

[malcolmzilla]

Titanium needles and jets are expensive!

[2smokeadam]

Thanks for the replies guys !! Going to try Malcolmzilla set up an see how it works.

[Ahamay]

Thanks for the replies guys !! Going to try Malcolmzilla set up an see how it works.

DO NOT try Malcolm's set up.,,300 jetting is completely different from 250 jetting.

[AJRJ]

Thanks for the replies guys !! Going to try Malcolmzilla set up an see how it works.

DO NOT try Malcolm's set up.,,300 jetting is completely different from 250 jetting.

I agree.

Also, if you're trying to jet a 2s in the winter without a carb heater, you're going to get good at making changes.

[Dobi]

the 2013 300 should be great with a 160mj, stock pilot and the L needle 2nd hole from the top. I had trouble with my 14 with an SX head and finally went to a jd jetting kit. I have never had issues jetting a bike before and have owned a few 2 strokes in my past. The jd kit, while expensive, made a difference right off the bat even though I had tried the same jets with 3 different needles. I run my bike all over BC, Alberta and Utah and never swap jetting. just play with the airscrew if I remember.

I am currently running a 158MJ and don't have any hesitation on holding it wide open while trying to keep pace with these 350xc's...

[Patrick]

I got the 2015 300 XC-W, it came with a 35 pilot, 7.0 slide, NECG and NECH needle, 165 main. Both are too rich for Maclean. I will be trying the NECJ or N3EJ or N8CJ
If none of those work (I'm sure they will) then onto that 38mm Billet Smartcarb collecting dust on the shelf.

[Dobi]

I got the 2015 300 XC-W, it came with a 35 pilot, 7.0 slide, NECG and NECH needle, 165 main. Both are too rich for Maclean. I will be trying the NECJ or N3EJ or N8CJ
If none of those work (I'm sure they will) then onto that 38mm Billet Smartcarb collecting dust on the shelf.

Its your main that is too rich. Go down to a 162 and the H needle. it will be good. If it is still not crisp enough, keep going down to a 160 or 158 main.

The Smartcarbs are starting to get bad reviews now. The dirt rider guys blew a bike up on one and finally gave up on it. Works well on a dyno, not in real world.

[erniebearskin]

I got the 2015 300 XC-W, it came with a 35 pilot, 7.0 slide, NECG and NECH needle, 165 main. Both are too rich for Maclean. I will be trying the NECJ or N3EJ or N8CJ
If none of those work (I'm sure they will) then onto that 38mm Billet Smartcarb collecting dust on the shelf.

Its your main that is too rich. Go down to a 162 and the H needle. it will be good. If it is still not crisp enough, keep going down to a 160 or 158 main.

The Smartcarbs are starting to get bad reviews now. The dirt rider guys blew a bike up on one and finally gave up on it. Works well on a dyno, not in real world.

I was running Smartcarb on TE250, and ended up ditching mine after 3 months, when it worked it worked absolutely amazing super crisp, lots of power and major gains on over-rev, but I could never get the float right, I believe due to the angle at which the carb sits on that bike. Float level is either too low and it leans right out at WOT, of course always at the worst time, or I'd raise the fuel height just 1mm, and it floods and fouls plugs like a motherchucker. I spent weeks going back and forth with the Smartcarb guys (who really did go to the ends of the earth to trying to fix for me) including replacing the carb after all major internals were swapped. Not sure if its the same on all KTM's.

[Patrick]

Yeah I had Smartcarb for the CR500 but it was a $900 mistake. Maybe I can return it as my year is coming up quickly. APT are really onto something but someone with deeper pockets should develop it.
As for the XC-W, the top end is working great (but I will go down to 162 or even 160), but its sputtering down low kind of where the 7.0 slide and needle start to work together.
I have the H needle on clip number 1 now AS 2.5 turns out and the sputtering slightly improved. Maybe keep the H needle and get 7.5 slide?

[Patrick]

For what is worth I finally got the 2015 300 XC-W where I really like it. It was pig rich from the dealer and unresponsive. The NECJ needle was the real difference maker for me.
Stock 35PJ, now same 35 PJ
Stock 7.0, now 8.0 throttle slide cutaway
Stock N8RG, now NECJ needle (the NECJ is a Suzuki triple taper needle)
Stock 165 main jet, now 158 main jet
Now runs more like my CR500 than an XR200. NECJ gave it that hard chug at low rpm like a CR500 rather than a Honda Civic low torque drone.
I had a JD Red needle and it sucked compared to the NECJ. Mind you it was 4 Celsius yesterday.
Just like the other guys here I might even try the L needle just to see what happens.
Cheers!