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with the lectron and fmf system the bike seems to pull 3rd gear easier in the corners. it smoothed the hit out a little bit and made it more luggable. im sure the stock carb could be made to work well and i plan on getting it setup correctly but for now and what i paid for the lectron im gonna leave it on. it was originally on a 125 so i had some tinkering to do, i got it running pretty well but its still a little rich. i got the metering rod set close to where it needs to be but im not sure how much the powerjet affects it. it feels rich right on the bottom but if i lean the metering rod out any more it gets a slight bog when im riding it, if i turn the powerjet out more will that help with the bog?
The PJ is for the mid-top. To fix that richness on the bottom-mid you need the correct metering rod for a 250.
They sent me the correct metering rod and I installed it. I talked to them today and I have the power jet out way to far. It ran ok but it was just rich on the bottom. They gave me a baseline to start with so I’m gonna set everything how they told me. I was just kinda adjusting it like a normal carb and apparently that’s wrong.
Here's rule #1 with a Lectron. Have a good digital caliper and use it to measure the metering rod set length. And only make small adjustments from the recommended length. They have a very small window that they work perfect in. Outside of that window they fall off to shit real quick.
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Yea I set the metering rod with my caliper to the length in the package said but I moved it some. I was riding it on flat ground when I first rode it with the lectron and it felt like it was too rich so I leaned the metering rod out an 1/4 turn and it ran good. It didn’t feel lean until I was riding a ripped up track and actually putting the bike under a load. It felt like I had a lean main jet and had some pinging. He told me today the pj should be around 3/4 of a turn out and I was at like 4 turns out. I shoulda read up more before I started messing with it. I have a better understanding of what I need to do now. I was just kinda going in blind.
Defo go with the Super X2 carb. The carb has the complete design and in its milder delivered tune, it is stronger than my largest STIC block internal needle jet tube.
Use the contact email. And if the time comes, PM me for any assistance in maximizing the tune.
That is my 2021 TC300, which i build 2 Years ago with a KTM 300cc Kit , Full FMF Pipe , Keihin PWK 38 ,Vforce 3 and some WP-Cone Valve, Trax Suspension
Can recommend this Upgrades as they are simple Bolt on power, Husky runs great so far with about 85 hours on it.
What are you using for jetting in the keihin?
TIA
Got to ride it with the 300 kit yesterday, it definitely pulls a lot harder now. It will pull 3rd gear like a 450 and is very luggable. I think dropping a tooth or 2 on the rear sprocket will be the ticket with it. I’m still having issues getting the lectron dialed in. I had it set where they told me to and it was way lean. The metering rod length on the package was 2.096” and I’m at 2.053” and still have a slight lean bog. Has anybody else had that issue?
I have a 125X buddy that richened his up after it destroyed his complete top end. But he likes it on his now kitted 144. D'oh! I do think he lacks experience and just kept riding it, even tho. it wasn't running as well as the prior mod'd Mikuni.
I talked to a tech from Slavens racing and he told me to start at 2.020” and work from there. I put it at that today and it was rich off the bottom and loading up so I leaned it out a 1/4 turn and am gonna go ride it tomorrow evening. I was starting to think something else was wrong but he told me I just needed to keep richening it up.
Drop kicked the lectron and sold it. Couldn’t get it to run how I wanted. Do I need the s4 needle jet with the 300 kit? Gonna order everything in the next day or 2.
Yes you do.
This is what we’ve been starting with in the 300’s.
Pilot jet 25 and main jet 460 to start.
Slide 5.5 (Kawasaki part 16025-0002)
Needle 42-75 on the 2nd clip (Yamaha part #284-14116-H5-00)
5/32” chainsaw file to notch the front of the slide.
A/S 1.5 to start, you’ll need to adjust as needed.
If he has to order a slide, I would recommend the 5.75. The 300’s really like it.
https://www.partzilla.com/product/kawasaki/16025-0003?ref=9473b5ea363f5…
Anyone have any tips or mods to improve the notchy upshifts? I’m using Redline ultralight shockproof gear oil, per TMR’s recommendation, but getting reluctance to upshift from 4 to 5th, sometimes 3 to 4 under loads, even when using the clutch.
Try a different oil. I use this and have always had smooth shifting still at 127 hours on he stock clutch. Motul 100963 Forcefield Transoil Expert Lubricant, 1L Volume https://a.co/d/gdP0dM5
Everything else the same? Everyone I know got rid of their 300’s so we never got to really dial it in.
Pit Row
I ordered everything and already have a bunch of mains and pilot jets in case I need to make a change. Everything should be here tomorow.
Yes, everything else stays the same. I’ve even used a 6.0 slide in the 300’s , but it gets a little lean in the cooler temperatures.
I ordered a Lectron after i dont want to waste more time with the Mikuni TMX.
But it was even worst with the Lectron mess around with that metering Rod , ordered another Rod but never get it Right .
After that i bought a good old Keihin PWK from a 2016 SX 250 and the 300 Runs without any Lean Condition, put a 180/175 Main jet for warmer condition and a 185 Main for colder .
That is just my Expirience but i can recomend that Keihin change , my 1990 KTM 250 runs ways better with the PWK than the 300 Husquarna ever did with a Mikuni or Lectron
I mostly just wanted to try the lectron since I saw on the ktm 300sx review ping did that Jaime Ellis said they work good on the 300. The mikuni has been on every jap 125 I’ve had and I never had any issues so I’m sure it can be made to work good. The yz125 I had always ran flawless.
I think both the Mikuni and Lectron are Good Carbs when you find a right Setting.
My Expierience the Lectron was ways better in Fuel Consumption compared to Mikuni and Keihin but down on Topend Power
But at the end i was tired, messing around with Metering Rods on Lectron , leaking Jet Block Gaskets and Slide Mods on the Mikuni
The Keihin is once set and forget
The bike runs almost perfect now. It was a little chilly today so i had to drop the clip one spot and turn the air screw almost all the way in. It probably needs a richer pilot but I forgot them at home so I couldn’t try it.
Is this the 5.75 slide? If you really want to fine tune things the 43-75 needle (KTM part #55431134400) is a 1/2 clip different then the 42-75. Let me know what you’re final settings are after you ride it a few more times and I’ll update the jetting thread for the 300’s.
Yea it’s the 5.75 slide. It feels pretty good now. Maybe just a touch lean when you are riding through pits with the throttle barely open. On the track it runs perfect.
It sounds like you need a slightly richer pilot (27.5). Did you notch the front side of the slide ?
Yea I used the a chainsaw file to notch it.
I forgot to grab the jets when I left so I couldn’t try the richer pilot.
i had the chance to ride a 24 300sx back to back last weekend and i must say i expected it to be better than the carb version but its not. it has a smoother powerband but is not any faster. i was surprised how much cleaner my bike ran with the jetting recomended above. the fi bike felt richer/dirtier on the bottom end compared to the carb. i am running a 27.5 pilot over the 25 but the temps have been in the high 50s low 60s and the 25 was right on the edge of being lean. i do have to adjust the air screw as the day warms up but it runs so crisp and clean. the carb bike does have alot more hit so its personal preference as far as how you like your bike to run. i need to get a longer silencer as i do have a shorty and i have been thinking about trying an xc head to get rid of some of the hit as it can be a handful.
Try the 43-75 on clip-2 as AJ said above. That extra richness will soften the zap in the power a little.
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