Upgrade to enjoy this feature!
Vital MX fantasy is free to play, but Premium users receive great benefits. Premium benefits include:
- View and download rider stats
- Pick trends
- Create a private league
- And more!
Only $10 for all 2026 SX, MX, and SMX series.
That is a really lean starting diameter to be using on a 125 cc bike. The pilot and main look like I would expect, but if it works, it works. Were those setting with a #7 slide as well ? There is just something different about the 22+ KTM based small bore bikes that is not the same as the previous years. I'm bummed that I didn't have more time to figure out what was different between them, but I almost have to suspect it was ignition/ecu related.
If you're referring to the Mikuni setting on the first page, you're good. They should work really well for you. It's the 22'+ (125/150) bikes that some people are having a problem with.
17+ 125/150 jetting
Pump gas/race gas mix, C12 straight
MJ 490
PJ 32.5
Needle Jet S4
AS 1.5
slide 5.0
Needle 42-74 on the 2nd clip (Yamaha 284-14116-H4-00)
Needle jet S4 (KTM part #55431021400)
PV 1.75 turns out from all the way in.
Fuel mix 40:1
This is all with a 6.5 slide. I have not tried the 7 slide yet. Maybe at some point I'll go back and try the CCM/CCK/CCL with a 7 slide. But at this point the bike rips so my motivation is down to mess with it.. haha. And the bike is only going to richen up as we start getting into spring and summer so I'll probably not be needing richer needles then.
Yeah, I wish we could figure out this 22+prob. Like I said, dropped my carb from my 21 Husky on there and it definitely did not run the same as my bike.
Yes, I’m in San Antonio so it gets pretty hot here.
The Shop
DeCal Works Huge Plastic Inventory of UFO and Polisport kits.
Luxon 4-Post Bar Mounts
$189.95 - $239.95
Good to hear! We plan to hit some Texas tracks this summer.
I’m using those needles for my 22 125 with a keihin 38 as 6.5 slide and they work fantastic for me! Digger helped me out with them. Bike has power everywhere.
Hi just joined the page would like to know if these settings work in Uk? Thanks
Hello, Please What settings for Ktm SX 250 2019 250 2019. Carb Mikuni tmx 38.
Country Czech Republice.
Temperature 20-30°C
The height above sea level is 600 meters.
This thread is a wealth of information and I really appreciate the time it took to pull together. My 2023 GasGas MC250 will be delivered this week and I just wanted to check if anyone has run the specs on the first page in one of these. I believe it's identical to the 2022 KTM motor but wanted to see if anyone has recommendations before I order the parts.
I'm riding at 600 feet above sea level in temperatures ranging from 50 Fahrenheit and up in the summer.
Thank you in advance
Dude! These settings are spot on. I ended up getting the 5.5 slide. It’s such a crisp responsive bike now.
My 5.5 slide and jetting from page 1 are on the way - looking forward to it and will report back!
We had our 125 rebuilt by Haeseker Racing and along with this jetting my kid ripped 7 holeshots in 10 motos this weekend. 2 of them were against a gate full of 250s in the 250jr class. Power is not an issue!!!!
Question…
does Elevation and track type make any difference to the jarring suggested on page 1?
Would you do anything differently for a Sand track jetting wise
highest Track we got this year would be
900ft above and the rest about 150ft..or less
That elevation delta won’t make a difference. Temperature changes will have more impact.
for sand go bigger on the main. I run a 520 in sand and am considering a 540. My boy rides sand at 3/4 throttle and above mostly and it can take all the fuel I can throw at it.
We’re in Australia so temps in winter probably range from 50-80’F at a guess
I find this jetting stable from about 35-90f. Below 35 I have increase the pilot and run a 520 main regardless of dirt. It doesn’t get above 90 where I live and when it does we all melt anyway.
a good moto buddy of mine just moved to Sydney. I’ll be shipping his KTM 250 factory edition to him in a couple months.
My brother and I have new 2023 GasGas MC250s, I put the second jetting option from the front page on mine (5.5 slide, Yamaha needle, 32.5 pilot and tried 35 as well, 490MJ, AS 1.5 turns out and tried other settings as well but minimal change) and his is stock. Both bikes have 1 hour since new. We are at 600ft and it was 43 degrees when we were testing. Both running Motorex at 50:1 and same fuel, 91 octane no ethanol.
He has a lot more bottom end pull and his idles normally while mine shuts off (recognize idle is not a focus but would be nice while I'm adjusting goggles or putting my gloves on). Any thoughts for things to try to improve bottom end? Thank you
Did you adjust the power valve? It needs adjusted with the jetting change since they effect each other.
Pit Row
Hello,
Need some help guys. I have a 2022 mc125. I was running pro circuit recommend jetting. Bike ran good.
i recently got the 150sx big bore kit for the bike. Had the cylinder and the head ported by PC.
Here are the jetting recommendations they gave me.
490 main jet
35 pilot
stock needle 2nd click (6bfy43-71)
air screw 2 out.
Bike runs like crap. It falls off so bad on too it’s dangerous to ride. Bike feels super fat wide open throttle. It’s like the bike doesn’t have a power band.
Would the jetting recommendations on page one help?
Could it be the i need to adjust the power valve?
Thanks for the help.
Absolutely wild the change that made - I had been paying attention to the first option for jetting and when I decided to go for the second I missed that. It rips now!! Thank you very much for all the time you put into this
So i put the exact jetting specs from page1 in my 2022 mc150. Bike runs like shit! Bogs/sputters from half throttle all the way to full throttle. Bike won’t even move really at full throttle. Yes, i did the jet block gasket also.
But look at this message i received from Jd jetting.
So i asked them “Are you guys saying that it’s actually a 6.0 slide, even though it says 5.0 on it?”
Waiting to hear back from them ,for a response.
i am really thinking about putting the bike back to stock. It’s unrideable with this 150 kit bummer
Not throwing shade on these setups at all they work great for some people. They didnt work for me. If you seach for my posts you will find the jetting I installed that was recommended from a ktm tech with a lot of experience. His jetting works awesome for me. I have the jetting and slide from this post sitting in a box. I may give it another go but really dont have a reason to now. I also went to a red PV spring with almost zero preload on the adjustment screw.
What size number is stamped on the slide you got?
It’s says 5.0 on the slide
Hmmm. So it's not exactly clear from them, are they saying they got #6 slides in place of #5 slides, or they got slides that are stamped #5 but really have a larger #6 cutout?
I wonder how long they've been having this mixup. For comparison, I just measured a #5 I got from them about 3-4 months ago. It measures 7.6mm from level to the top of the cutout arch.
That’s the exact same question i email JD jetting. Still waiting on a response. I will share once i hear back from them. Here are some measurements from the “5.0” i just received.
OK.. that looks the same as the one from a few months ago. For more comparison, I pulled the #5 out of another bike that rips. Bought this one almost 3 years ago. Also looks the same as these recent ones. So it will be interesting to see what the prob is JD is talking about.
Update from jd jetting.
So I just read through all 32 pages over the course of a few days and was all excited to try the setup on the first page only to find out it doesn't with with the 22+ bikes?
I just picked up a new to me 22 tc 125 with 17 hours. I had everything in my cart ready to order, but should I hold off? I mostly ride my 450 but iv'e had an 04yz125 for about 10 years that I often play on and this stock husky is lightyears faster as is so its hard for me to tell if it's running as it should. (iv'e never been one to nitpick jetting due to my lack of knowledge)
I haven’t opened up the carb to see what jets are in it, but it starts up very easily without the choke, will load up a little bit while warming it up on the stand but it will clear out pretty easily, and seems to fall a little flat up top on over rev. I THINK the only time the bike bogs is just to me being lazy and not down shifting, however the bike recovers well with a little clutch work.
Long story short, do I try the page one jetting specs or just forget about it?
Honestly that’s gonna be your call. I just updated the 125 jetting a few minutes ago with a better setting that FCR01 has been testing that’s a good starting point. The ‘22 engines have that known bog, but it seems that not all of them have it or some people just don’t notice it because they don’t ride in that rev range that it happens in.
Post a reply to: 125/150/250/300 KTM/HUS/GG jetting thread