2024 Yamaha YZ125 JD Jetting Kit JDY020. The solution to the YZ125 Jetting Issues? Will See!

[@IBreeeZzTV]

Great video mate x

[@twistymcslide2]

i think the problem with the OEM needle , is that its stepped . the steps even when matched to the correct jets, cause irregular flow , and the stepped needles are way more dependant on the jetting to work right , vs the JD kit which uses a smooth tapered needle ( suzuki makes the needles as far as i know , it's just that JD did their homework to figure out compatibility ) . i have an Apex head , Bills pipe , T2 fuel , and JD kit ,and it made a world of a dif. i really like the SX Dome , more for top end , vs the MX dome . the MX doesn't make as much use of the over rev compared, both evened out the low/mid range though, got rid of those muddy parts of the throttle , and i think that's more so the needle over anything else.

[@coalcountryrider]

When you installed the head did you have to change the jetting? I have a 23 yz125x with the same stock jetting issues. Looking to get an apex head with a jd jetting kit to pair and am wondering to affect the jetting

[@GOATbro_Australia]

I changed the jetting to JD Jetting recommendations. That is based on a stock engine. The jetting is perfect for my setup with the VHM head, so my guess is it should work well for you to with Apex. Hope that helps.

[@brianwilkins2311]

I ha e a 23 yz125x and having issues I'm looking to the jd jetting kit as well! It worked for yalls issues correct?

[@coalcountryrider]

@@brianwilkins2311 make sure you order the right kit unlike me since carb changed from 22-23 year. Going to probably get a lectron instead.

[@personal8795]

i got the same bike blowing spark plugs like crazy. im at 590 feet elevation. what mix do you use ? i was mixing factory recommended 32/1 now im 40/1 still blowing. im gonna rejet it soon. i do alot of muddy trails not rippin it like im at the track. not riding that power band alot.

[@GOATbro_Australia]

Manual actually recommends running 30:1. I run Maxima 927 at 32:1. The JD jetting kit and the recommended setting in that kit are critical to a good running YZ125. Mine runs perfect. I am now running a Smartcarb, and even better. It also makes a big difference in overall power and smooths out the power a little. But it's very expensive. JD Jetting kit at the very least is needed for this bike to run really good.

[@personal8795]

@@GOATbro_Australia sick thanks man. Can you drop the smart carb link ? I think I’m gonna go that avenue just looking at my options on it and where to get one.

[@GOATbro_Australia]

@@personal8795 smartcarb.com/

[@ivansostaric738]

After testing the bike, did u find it to help? I got one for my 23 and it bogs down at 1/8 throttle. Do u mind listing what jets u have currently and air screw? Thanks

[@GOATbro_Australia]

Sure. I typically ride at around 2400 to 3000 ft elevation and from 60 to 75 degrees F. This kit fixes the jetting on the YZ125. Mine jetting is: Main 170 Pilot 50 Needle JD Red in 4th clip position Air screw at 1.5 out Hope that helps!

[@ericmahoney5916]

Hey, I see your main is 170... my instructions say my main is 185 for both cold and warm weather. Did you land on the 170 by personal experience or following the instructions.

[@GOATbro_Australia]

I went with exactly what JD Jetting recommended.@@ericmahoney5916

[@ericmahoney5916]

Apon further review of the the play...I think my problem is that I have the 125x model so my jd kit came with different instructions on what jets to use. Are you still happy with the kit?

[@GOATbro_Australia]

@ericmahoney5916 I am. I have no jetting issues. However I am going to try a Smartcarb. Very interested to see how it works on a 125.

[@braydenhoffman]

When i slowly rev up my 2000 yz125 in neutral it starts to skip and sputter at 1/4 throttle does that mean my jet needle is too lean even though the clip is at the leanest position so the highest it can go what should i do

[@GOATbro_Australia]

That can be a number of things. If you put a fresh plug in and run it, I would check the color and see if its rich or lean, then adjust accordingly. If this just started happening, then you might have a deeper issue. The needle jet does impact jetting from 1/4 throttle up to about 3/4 throttle. You might need a different needle (leaner or richer) depending on what your seeing on the plug. But again, it could be other factors at play here. Hope that helps.

[@braydenhoffman]

@@GOATbro_Australia ok thanks brother when i use a 9 plug it goes fully black and files after a few hours of hard riding and when i use a 8 its tan but it still skips 1/4 throttle

[@isofly28]

Isn’t a 50 pilot jet awfully too lean?

[@GOATbro_Australia]

Appearantly not. Runs perfect. This is JD jetting recommended and works with their needle.

[@isofly28]

@@GOATbro_Australiahow long have you been running the setting for? I have pilot 50 main 170 and red needle on 4 clip. It ran good. It didn’t even turn off on me when it was just idling like before. It even engage a few times on first gear without even giving it gas lol But I’m just concerned if a super lean pilot will effect the engine since i think it’ll be running hot?

[@GOATbro_Australia]

@isofly28 for a few months now. Keep in mind that the pilot jet only affects your mixture up to about 1/4 throttle. Your mostly running on your needle and main jets, with the main being much richer and the needle is set to a fairly rich clip position, so overall your leaner on the very bottom, but richer every where else. Your plug should be fairly dry and tan in color. Should be good.

[@bradsimmons2071]

Looks like you made the video before even testing the JD kit. Not very helpful video. Any follow up. How did it run? Looks like you may have abandoned it and gone with a Smart Carb so not good?

[@GOATbro_Australia]

Sorry yes, I did test the kit, and no complaints. Ran smooth and clean. A definite improvement over stock. It's worth the money. As for the Smartcarb, that was mostly to satisfy my own curiosity and it surprised me. It added significant power across the board, especially on the low end, and runs even cleaner and smoother than the JD kit. In my opinion, it was worth the expense. The JD kit is certainly worth doing if you can't afford a SC. Hope that helps, and sorry again for that lack of detail.