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Only $10 for all 2026 SX, MX, and SMX series.
I’m going to quit over thinking it and just go with a needle with a bigger straight section if the burble is a problem. I would say if the stock jetting burble bugs you then the Y4 and 2026 getting is going to seem better but I think the lean pilot and straight portion hurt torque out of the hole. And then the richer power jet and main effect rev quickness and over-rev.
Will see I guess ?
Honestly I just want something I’m happy with in 90% of the riding I do. The OEM jetting really only shows it flaws (burble)in practice /hardpack situations where I coast off throttle(downhill. Sweepers mostly) otherwise in race situations I never notice it ( to busy concentrating on other things)
HFS
Have a buddy with the GYTR setup (68p/70pj/y4-3rd/165m)in his bike and he rode mine with oem(72p/35pj/NYDF -1/165m) noticed the slight burble but commented roll on from closed throttle significantly better quicker response -rest same ish.
He’s thinking of trying a 70p. Then maybe see if the 70pj is really necessary and go back to the 35pj.
We are confused if it’s the richer pilot( I do find a rich pilot feels better then lean) or too rich on power jet?
What elevation and temperatures did you test this jetting at?
Interesting they have superseded the older airscrew for the 22-25 models (4SR-14105-00-00). Now you can only purchase the airscrew from the gytr kit which is the same as 26 model noted by Rocket (4SR-14105-01-00).
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About 800ft around 65-70 degrees. I'm going to try a 70 pilot with stock air screw. It seems like it wants a little more fuel down low.
Rode my 2022 yz 125 with the jd jetting red needle specs for 3000 to 6000 feet.
50 pilot
Red needle 3rd clip
168 Main
Stock powerjet
0.5 turns out from fully closed airscrew
Super strong rollon and low to mid response.
Seemed like a Richer Main could help as it felt weak on top.
Will also try a 52 pilot since i was riding at 6000 feet and i don't feel there will be margin to adjust once i go riding at 4500 feet.
Has anybody tried a 52 pilot with the jd jetting red needle?
I have 2200f 52p for the most part it gets rid of the quick throttle bog.
2200ft elevation 20c (70f)
thanks i will try the 52 pilot and after i test the 52 pilot maybe go to a 170 main.
Did a little testing with the Y4 setup this past weekend. Started off with 70pilot, Y4 clip 3, 168m, 70pj, and gytr a/s. Running straight T2 @ 500ft - 60° F. Definitely rich down low off the pilot circuit for me. I was getting a really bad lean surge around 1/2 throttle so I adjusted clip to position 4. Dropped pilot down to a 68 still seems a hair rich. Going to do more testing later this week likely dropping the pilot to a 65.
The initial roll on has been my main issue jetting the bike it’s been tricky to get right. I feel like diggers setup was the best the bike has ran. All circuits transition well and pull hard.
So I have tried many jetting specs including jd jetting and others. I have finally been able to get a hold of a CCL needle from diggers jetting spec. I’m am basically at sea level in southern new jersey , ran a 180 main jet, 55 pilot at about 1.75 turns out on air screw , and CCL needle on third clip position with a 5.5 slide at 32:1 klotz on 94 on a fresh top end at 40 degrees Fahrenheit with a apex mx head and I cannot stress enough this is hands down the best jetting for this bike possible. I have tried everything, I have at least 10 main jets, 10 pilot jets and at least 15 needles, tried every combination including the Y4 needle and the 2026 jetting specs and this thing runs flawlessly. No bog, real 125 power. highly recommend hands down. I’m not sure what it will change to in warmer weather but this is the best jetting I have used so far. Just an fwi it ran this way on a moto track, the bike I have is a 2024 125, not an X model. I do not ride trail or anything so I do not know how it will perform outside of mx.
I Will try a 52 pilot with the jd jetting red needle 3rd clip and 168 Main for 1500 meters and 18 deegrees celcius. With the cooler temps the airscrew is only half a turn out
Tried the 52 pilot air screw at 1 1/2 turns out gained roll on power and got rid of the bog.
This bike is running great!
Did you keep the stock powerjet?
Revisited pro circuits settings for pump gas. I’d say it’s a fairly close baseline to start. It was around 60-70° for me outside. Pilot is spot on, found myself jumping between clip position from 3-4. Bike seemed slightly lean up top. I was going to test a 168 main until it snapped off in the carb. There did seem to be a very fine window of adjustment on the airscrew. I was using the newer airscrew which comes in the y4 kit which has a steeper taper.
Switched back to the old digger ccl setup (55p, 6.0 slide, 182 main, ccl-3, a/s 1.25-1.5 out (60-70°).That single taper needle works so well and is much easier to dial in. I do have a slight hesitation when I chop the throttle at lower speed in 2nd gear. This isn’t really an issue when riding on the track.
Is it worth going to the 5.5 slide at all?
I’m going to get the updated parts from the 26 and test them out. Never really liked the airboot on the 22-25s. Curious to see if the 26 is much different.
This is the 26 air boot. Shape seems roughly the same as the prior models. Only real difference I’ve noticed was the removal of the shroud at the 6 o’clock position. The opening at the 4 o’clock I believe is new as well. I’m still waiting to get my hands on the 26 airbox to see what is different.
Not sure if anyone has noticed, but the airboot on the 22-25s is the same as the 21 equipped Mikuni model (1C3 part no).
This is a 5.5 slide, CCL 4th clip (2nd richest), 180 main, 55 pilot, 70 powerjet.
It smokes alot in the video. I just replaced the piston ring, however it rode the same with the old set of rings.
Which direction to go? The erratic behaviour would incline me to think it’s lean.
Pit Row
Last video is with the needle moved to the second notch from the top.
Hey all,
I got my hands on a 2023 yz125. It has 10hrs on it since new (old man owned it before me) But I got a big problem here.
Details
Currently running @digger jetting specs and its wayyyy better then stock. BUT im getting that nasty mid range lean Bog that alot of folks are mentioning.
Setup:
This setup is great as long as you STAY ON THE PIPE! But for me its not possible. I spend alot of time riding in 1st and 2nd gear squeezing between tight trees or dodging rocks and logs on clapped out trails. And I love to haul ass on the straight sections. So im no MX rider but im not specifically a trail snail 🐌 either. So I spend ALOT of time riding exactly in that mid throttle problem zone.
as others mentioned when around 4500 to 5500rpm (Tusk Tach) mostly in 2nd gear moderate pace I crank the throttle and it'll bog and sputter for a second or two then come back on.
There's alot of technical spots I ride in old quarries and such with lots of rocks and slow speed stuff. Had to drop the 52 pilotbdown to 50 because it would load up so much. The 50 Pilot is Sooo crisp now off idle. Its so responsive and doesn' load up like the 52 pilot.
Anyways it didnt make the mid range throttle bog any worse so the bottom end is good and the top end is good.
Just this mid range is eating my soul..
Im going to try clip #5 today on the CCL needle but I am wondering would it just be better to change to a different needle? What is the next needle i should try? Is there something I am missing? Should I use a 5.5 Slide instead? If so where do I buy one?
Somebody please help. Lol
I need to fix this before my 4th July riding trip. I gotta make this run like my buddies ktm EFI or I will never hear the end of it!
I know you said it loaded up but did you test the 52 pilot thoroughly enough? Was your air filter over-oiled? I was able to run a 55 pilot near sea level without that issue and I'm not on the pipe everywhere.
I put a good 6 hours testing the 52 pilot.
I was at clip #3 for a couple hours and dropped it down to clip #4 seemed to run better. I think it narrowed the gap of the problem area alittle. Although still there.
As far as the 52 pilot goes its not bad but i had to make sure i would clear it out. Or it would definetly become sluggish on me after a while of creeping through the woods.
the 50 just feels better. Instant throttle response. No hesitation. Less build up etc.
To be fair I do oil the F#@k out of my air filter.. lol Still trying to get the hang of that. Just got back into the dirtbike world after many years. So trying to get a feel for it. Figured too much is better then too little. I use the Maxima FFS oil. Some sticky stuff right there!
Hate to admit but last time it was dripping out of yhe airbox onto my swing arm. 😅 I'll back off the oil...
Maybe i can experiment with the 52 pilot again. But in the mean time what do I do about the midrange? It still has the lean bog at mid throttle even with the 52
I would try one of the N3xx needle settings mentioned earlier in this thread if midrange is still a problem. I've not heard of or experienced lean conditions when using the CCL in the 4th clip position though.
So I finally got a hold of a 26 airbox. I’m curious between the CDI, airboot, and airbox if there is much difference. Found some older threads on thumpertalk when the 22’s came out. Guys modified the airboot removing the shroud and cut holes in the bottom of airbox. Haven’t heard of any jetting woes with the 26s.
I'd recommend to try Y4 needle. It's been best for me
I did not get those CCx or N3xx needles work as good. Tried several.
Im curious, Have you tried the y4 needle with the #6 slide? I actually do have the GTYR Kit. But never tried it because I ended up going with Diggers specs.
Heard the Y4 needle was a flop for most people.
Wonder how it would do if I kept the #6 slide, 50 pilot and 182 main. Even though its designed to be used with the stock #7 slide. I may give it a whirl.
i opened the bottom of the airbox and removed the nub that blocked the slow circuit mesh on the inlet of the carb on my 2022, im riding between 1500 and 2000 meters. i ran the N3CG needle and the JD jetting red.
So far i love the red needle #3 stock slide and power jet, 52 pilot and the suggested main for the altitude and temp which i think is a 168. the 50 pilot that jd jetting suggests was lean and bogged.
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