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i just picked up a lightly used 22 tc 250, what are some of the worthwile mods for these bikes?
Do they still come with the warped reed cages?
what aftermarket pipes work best?
what jetting are people running?
im really thinking of doing the 300 kit, any reason i shouldnt?
i have a cone valve/trax combo with the linkage off my 350 to put on it.
Find the jetting thread on here, that is job #1 on these bikes. With proper jetting and gearing, the bikes are very effective. Probably not a bad idea to get head squish set correct, they leave a lot on the table stock.
Do they come with the 2 peice heads like the 125s have.
Jetting is #1 on those bikes and is night and day different. Get it jetted right and and adjust the power valve then get a PC pipe and long silencer and you’ll be good to go. I never messed with squish on mine so I have no real comment as I never thought it necessary. The reeds are warped stock, but when the bike is running they are forced closed just like they should be. I put 90 hours on the stock warped reeds and top end before putting in a new piston and a rad valve. Didn’t notice any change in how the bike ran.
If you feel you need more power T2 mixed 50/50 with pump gas mixed at 60:1 (gives you roughly 50:1 mixed) is a noticeable power increase. I didn’t notice much if any power difference between 50/50 and straight T2.
I currently run 14/52 gearing and for the most part it’s perfect, but there are sections sometimes that 2nd is too short if it’s a fast turn, but too slow to pull 3rd without extra clutch work and 4th down a really long stretch runs out up top. This depends on your ability tho, as I’ve gotten faster I think lower gearing would be helpful.
are there any benefits to buying a lectron or the kehein carb off the 16 and older model?
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Your wallet will weigh less so there’s that.
fair enough. ill take that as they are not worth it.
Honestly can't recommend AJ and the guys jetting thread enough. I did it on my tc250 now workin through my 125sx.
Grab the slide, the jet block gasket, the jets and needle, do it all and do it properly man. Scratch that whole headache off the list from the get go.
Nothing wrong with the Mikuni after that, think how much people love YZ's with their Mikuni.
These bikes are top shelf stuff, jetting, PC or FMF silencer (the longer one, not the shorty), suspension set up, then live the dream dude 🤘
A little trial and error with the different power valve springs and setting is interesting too but that's a personal preference deal.
Since you mention a 300 kit, it seems like you want more power than a well tuned carb or pipe provides.
I know a 250SX rider that installed the new STIC Super X carb and he is digging the much stronger and wider powerband. Said he's not getting pulled by 450's any longer and slips the clutch far less. The Super X should give you the stock peak hp level 1k rpm earlier and extend it 1k-ish rpm on the over-rev. Between that expect an additional 5-6 hp. The cast Super X is more akin to a race tuned package.
I run one on my 200SX with the slowest G2 throttle tamer cam. Yesterday I mixed it up with a couple 450 buddies on a GP style track. One commented that he can't believe how hard the 2hun pulls when he followed and the other said he stopped trying to keep up. The stock power is sluggish by comparison. Roll-on power is now so good I don't need to clutch it for jumps and whoops out of turns, unless corner speed drops.
i got to ride the bike today, once i turned the power valve adjuster out the bike really come alive. the lingering revs when you let off the throttle is very annoying so the jetting definetly needs work. i had a 300 kit in mind when i bought this. i was gonna get a new 300sx but im hesitant to spend 10k on a 2 stroke. i got this bike for 6k so im willing to spend the money to get it dialed in.
Sounds like a good move right now.
KTM will figure it out and I hope and expect people will get the modern FI 250's/300's dialled, but the last gen of KTM/Husky/GG 250's are the pinnacle of a simple, clean, two stroke race bike imo.
I found this fmf system used on Facebook less than an hour away so I went and picked it up. It’s pretty much brand new but I’m Not sure how the four stroke looking silencer performs but I only paid $300 for the system so if it sucks ill buy a regular silencer.
I found the 300 kit online for $750 so I ordered it and I think I’m gonna send it to tmr and have him massage it. He told me he will give jetting specs so I’ll wait to mess with it until I put it on.
Where is the 300 kit for $750 ?
That FMF should be sweet man, it's only the shorter silencers you want to stay away from as they make them a little barky and cut the top end a little short (which is already a little bit stunted on these 250's, though I was never fast enough for it to be an issue or really notice it negatively against a YZ)
AJ's jetting specs from the thread change the power character of the bike a lot. Stock, there is no overrev and it is rich down low and through the middle and revs lazily due to the jetting and the PV setting. Once you get it dialed on AJ's specs it revs quickly and cleanly and keeps pulling on top. It totally transforms the bike and allows you to ride it correctly on a track, stretching gears to get jumps out of corners, etc. I've tried both the 5.5 and 5.75 slide and the 5.75 was definitely better for me, likely since it was 1,400 - 4,500ft and 85-105 degrees. I might try a 6.0 at some point also. The 300 specs in the thread state a 5.5, but I really suspect if these were developed further a 300 would definitely benefit from a 5.75 or 6.0, depending on conditions. I know you said TMR will provide jetting specs for a ported 300 cylinder, but I kind of suspect they will be minimal changes and will not address the slide, needle-jet, and possibly needle. You're really hamstringing yourself with these bikes if you keep the stock 4.0 slide in.
I have a 5.0 slide out of a Mikuni. Maybe I’ll stick it in and play with it some for this weekend. I had an rm125 I big bored and had issues at first getting it jetted correct. Seems like the big bores like a leaner setup.
You need all the brass to change out too, not just the slide.
Yea I have a bunch of Mikuni jets, I’ll look and see which ones I have.
Pit Row
https://www.vitalmx.com/forums/Tech-Help-Race-Shop,42/KTM-HUS-125-150-2…
needle jet too
I’m gonna look into getting that but for now couldn’t just put the slide in and try different main and pilot sizes? I’m sure just the leaner slide would clean up the richness in the bottom some.
Do it all or not at all so I’d hold off until the rest of the parts come in. All these parts work together, we switch to the S4 to richen that circuit back up to match the lean slide since the 5.5 or 5.75 pulls fuel harder than the 4.0. Running the stock S1 with the 5.5 or 5.75 will be way lean on the bottom end.
I’ll see about getting that stuff ordered then.
Good call. Better safe then sorry. Be sure to adjust the power valve also when you get the new jetting in as it also affects the jetting. I start with 1 3/4 turns in from all the way out and adjust to your liking from there with the stock spring.
I purchased a TK Head along with the jetting recommended on here. A whole new bike.
The 300 kit came today and wow is that a good deal. It’s ready to bolt on. The rings are even on the piston. I found a used lectron billetron so I bought it. If I don’t like it I should be able to sell it and not lose anything. After watching the 300 videos that ping did and them talking about how good they work on 300s I figured I’d spring for one. It appears the 2.1 silencer I bought is the shorty version so I may have that for sale if I’m not happy with how it runs. I always preferred the shorty on the yz250s I’ve had tho.
Gotta love 2-stroke mods, BANG for the buck!
Not sure I believe the hype on the STIC carb, I’ve heard many reports from users and dyno runs that have lost power with the system.
4 yrs with STIC products. I'll curb my enthusiasm here.
If it wasn't for the batch of bad pilot passage alignments, the issue is the tuner. I can say that with confidence, bc I know my track and trail results do not reflect what you reference. Does it occur, certainly and that's your valued information source. I get it. Though IME, I don't miss the mark and I'm not alone. So I will say that perhaps your sources are outliers and thus you have achieved confirmation bias, perhaps.
I've assisted a number of ppl. The more knowledgeable ppl easily get off into the weeds on their tuning compared to noobs that reach out for help. Ppl also tend to get conservative with my guidance and fall short of the potential. They say they're dialed, which is still well above any other carbs power level. I let it go, as I tire of the resistance and random choices made.
If you understand gas lift technology for a low pressure oil well, you'll understand a key STIC component in creating a more rapid fuel up take and the leaning of the mixture as the fuel level drops in the float bowl. If you don't, then of course please continue on as an uninformed skeptic.
Word to the skeptics, go buy a TBI and dump a load of cash into it like everybody else will soon enough. My turn to be the skeptic. Doh!
IMHO, at this point in time, if anything. The STIC should be rejected based on excessive power output for many riders, as that was the intention.
Lectron will be soft off the bottom. Maybe that helps traction and is less tiring as well.
If you want more beast mode grunt and over-rev that matters, a used Keihin and STIC metering block is the ticket. Eventually this will be a no-brainer, but until then, power is left on the table.
Are you suggesting a Keihin and the STIC metering block kit over the STIC Super X complete carb?
The current website for STIC seems to lacking objective information. Is that the correct source to obtain application, technical support and pricing info?
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