I have a 22 yz125 and have been experiencing problems with the jetting and the bike running since I got it. I wanna take the time to finally get the bike running mint now that I have the time and the warm weather is here.
To start, I have always run Yamalube2R 32:1 which I think is acceptable for my riding style (10min road ride to the trails and fast paced in woods)
My plug fouling issue started when I first got the bike. I heard of the JD jetting kit so I tried it, it made the response better and helped with the plugs but there was still a lean bog no matter which needle I changed to. Also the plugs still fouled after around 1-2 hours of riding.
I tried changing the mix ratio (might try again with dominator or moterx instead of yamalube) but I feel like increasing the oil mix to 40:1 from 32:1 is unsafeish for riding on the road to the trails fast.
I heard the rave about the pro circuit jetting and the y4/y3 needle but they are sold out everywhere. Same with the slide.
as of right now what are you guys running on your bike (22-24 yz125)?
im at around sea level and temps are in the 80s rn for southern Ontario.
Any tips or suggestions would be great, thanks!
current jetting:
170m
50p
red needle 3
stock slide
stock power jet
30 hours on the bike (haven’t rebuilt(factory piston))
Fresh Notoil filter
32:1 yamalube 91
Years ago I had an unsolvable jetting problem and so I made a jetting calculator to help me get it jetted right. After 1.5 years of suffering bad jetting (stock bike from Suzuki factory) I finally got the jetting spot on thru the whole throttle range, something few bikes have. I recommend people get my spreadsheet or hire me to help them figure out what to do. www.dragonfly75.com/moto/carbjetting.html
Main problem with this bike (IMO) is too rich on the pilot circuit and lean on mid throttle. When you go down on the pilot you create a bad lean bog.
I can say what worked for me. 24 YZ125. I bought a #6 slide (#7 stock), CCL needle (3rd), 55 pilot and 182 main. Runs well.
What I tried: many different variations with the OEM needles and jets. JD kit with blue and red needles. Was too lean on pilot circuit to mid throttle with their recommended setting. Their red needle 4th clip, 60 pilot and 170 main worked pretty well, I ran it for a bit.
I waited quite awhile for the GTYR kit with the Y4 needle. I read a lot of good stuff about it. Unfortunately for me it was a let down. Pro Circuits recommended settings were way too lean to ride. I messed around with different pilot jets and clip positions but never got it to run like I wanted. If you want to buy the GTYR needle and jets DM me and I'll mail them to you, they didn't work the way I wanted.
How did u come upon the CCL needle and that jetting? I was reading about the slide and how this carb is basically built for the 250 so the #6 slide will help with that and is what it should of been from factory
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I think it’s not worth my time with the gytr and pro circuit jetting. I’m going to try to find the ccl needle and #6 slide online (pray it’s available)
Do all these P/N check out?
JDKH11 - Keihin PWK Carburetor #6 Slide
JDKH16 - KEIHIN PWK/PWM Cable Holder
4MX-14943-94-00 - MAIN JET 182
4MX-14948-09-00 - PILOT JET 55
16009-1387 - NEEDLE R1370E
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