Jetting KTM 300 XCW

Got a question about Offroad Ontario, here's the place to get it answered.

Re: Jetting KTM 300 XCW

Postby mkeeping » Wed Feb 21, 2018 2:31 pm

timw wrote:After a full season of riding, I'm wondering what everyone is using for jetting settings on their 2017 KTM 300's. If your your happy with your settings please share them. Including if you have completed the slid mod, replaced the reeds, etc. Would love to get my bike running 100% perfect instead of 90%. Thanks

Here are the specs that I ran all last season and was quite happy with:

2017 TX300

43-73 2nd clip
R8 Needle jet (Stock)
450 Main
40 Pilot
AS 1 3/4
Slide mod
Airbox mod
Yellow spring factory position

We're running pretty similar settings.
Posts: 21
Joined: Tue Jun 10, 2014 2:39 pm

Re: Jetting KTM 300 XCW

Postby Hamburgler » Sun Mar 18, 2018 9:18 pm

'17 300 xcw,tried every mod out there and finally switched to a 38mm Keihin,havent looked back.
Posts: 4
Joined: Wed Apr 30, 2014 9:06 pm

Re: Jetting KTM 300 XCW

Postby Max9001 » Thu Mar 22, 2018 1:59 pm

found n8rg (stock needle) on clip 2,
172 main
35 PJ
is the best setup ever. no joke.
ktm 300 love run a little rich to give the more power delivery as possible.
is not correct to jetting the bike depending of the plug color because a coffe brown is result less power delivery than dark brown color.

another similar setup is n8rh clip 3 needle with same main and pj. it will give you the best performance.

be patient with the air screw adjustement. it is very important to found the best adjustement to have crisp response transition between the PJ and the needle!

ktm 300 xcw 2015
Posts: 6
Joined: Sat Jun 03, 2017 11:04 am
Location: QC

Re: Jetting KTM 300 XCW

Postby Clayfan » Wed Apr 11, 2018 11:25 am

2018 KTM XC 300

I was actually quite surprised when I picked this bike up and got an hour on it before the snow in December how close it was stock to running correctly.
Carb is Mikuni
I ended up in WVa Temps 4C to 25C Elevation to 2500ft a week ago with
27.5 PJ (Stock is 25)
42-75 Needle 2 clip ( stock is 43-75 which is only 1/2 clip richer through the range of the needle)
430 Main (Stock is 430)

I had a little richness transitioning from the PJ to the Needle so the only tweeks I made was richen the PJ and lean the needle (Tried a 35 PJ but that was entirely too much in this motor)
No air box mods
No Slide Mods.
We will see if this jetting holds up when the thick, hot air of summer gets here but I think the change KTM did to the Jet Needle from 17 to 18 made this bike much easier to get along with than the 2017 SX 250 we struggled with last season.
Posts: 47
Joined: Tue Oct 26, 2010 7:48 pm

Re: Jetting KTM 300 XCW

Postby Craneop » Mon May 28, 2018 7:59 am

Lectron carb solves alll problems
Posts: 3
Joined: Fri Oct 06, 2017 8:26 am

Re: Jetting KTM 300 XCW

Postby Js300setup » Fri Jun 01, 2018 4:46 am

Collection of some KTM300 Tuning Weblinks: ... two-stroke

Power Valve (4500- 8400rpm)
Yellow- factory mid (lower gear feel hit)
Green (heavy spring= Soft hit)
Red (soft spring= Aggressive hit)

Power Valve Screw: Turning out lowers power 4.5-6K. Turning inwards or a stiffer colored spring loses power 6-8K rpm.

Map Switching Details (23Jan14)
Tuning for: woods, desert, trail, play or racing applications. *Guide: Unplug= Soft map (takes bark out engine): rock-hard or slippery surfaces. Plug In= Performance map (factory). ... two-stroke

Torque Chart: 13KTM300xcw vs SXhead

2-stroke (200, 250, 300) verses
4-stroke (250, 350, 450): HP & LB:
Posts: 5
Joined: Mon Mar 20, 2017 3:25 pm

Re: Jetting KTM 300 XCW

Postby drumbell » Tue Jul 24, 2018 8:33 am

Sold the 2016, now have a 2018 300 XCW. Read all the nightmares about the Mikuni Carbs. Straight away purchased a JD jet kit for the 2018.
Following JD settings bike was almost spot on from day one.
With blue needle bike was sometimes a little hard to start and was running rich, sploosh running out pipe.
Have gone to the Red needle bike runs great everywhere, no splooge, no stutter or bogs. pulls like crazy to WOT, starts first try every time.
I ride around 400ft above sea level temps 0-30 degrees C. I dont like messing with jetting all the time, the only thing I occasionally adjust is the air screw. 1/4 turn in or out, and only when im at the extreme ends of the temperature.
Current settings
Main 440
Pilot 30
Red needle Clip position 3.5
AS 1 3/4 out
Only mods I have done is cut away that little wing on the air box cover that restricts air flow. I did that right away so dont know if it made a difference.
Dave Vet 55
KTM 300
Posts: 118
Joined: Mon Aug 27, 2012 11:42 am

Re: Jetting KTM 300 XCW

Postby JTQ » Sun May 05, 2019 9:27 pm

FWIW I just setup a 2009 300 XCW with Dave's recommendations which were spot on:

Necj needle on 2nd clip
170 main
38 pilot
AS 2 turns out. (1 turn out at current cooler temps)

Thanks for posting that Dave!
Posts: 241
Joined: Wed Aug 03, 2011 2:51 pm

Re: Jetting KTM 300 XCW

Postby sminnillo » Fri Aug 30, 2019 5:31 pm

2016 300XC-W... anyone installed a Boyesen RadValve ? Recommend going down 1-3 sizes on main. Stock is 172, i think. Curious what others have done after RadValve install?
Posts: 1
Joined: Fri Aug 30, 2019 5:25 pm


Return to General Discussion

Who is online

Users browsing this forum: No registered users and 5 guests