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Only $10 for all 2026 SX, MX, and SMX series.
Super excited to get some ride reports out of this 300! Should be a great bike for the Vets who grew up on two strokes but enjoy the power of a modern 450, seems like a great compromise between the two. Sad to see no 150SX, wonder if they’ll bring it back at some point, maybe go back to a “true” bored and stroked 150 like how they made the 300SX a true 300.
New bodywork is growing on me, the spy photos of the factory bikes gave me a bad taste in my mouth. What a great time to be alive for these advancements in motocross!
We all complain about the sport of MX dying and that we need 125's as a cheap beginner bike and stepping stone for kids moving up from mini's. Making them unnecessarily complicated prices people out of the sport. I guess if only the KTM is EFI and the Husky, GG, and/or YZ are still carb'd then there's options all around.
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As for the sport dying, well yes, but then again, everything alive is dying, including the planets resources. It's a great time for mx, so live in the moment and have fun as you can.
Hopefully the 150 will return, and people shouldn't get too deep about bore and stroke debate that was pushed by the mags wanting to sell their friends proprietary pistons, it's all about the porting imo.
And for somebody coming into the sport: no kid today will have any knowledge of carbs and most of their dads too, which leads to crappy running bikes and a lot less quality track time.
My 2017 SX125 and it’s Mikuni carb drove me nuts with how sensitive it was. I had a lot of days with more wrenching than riding and always gas on my hand. In the end I swapped it for a Keihin and now I‘m good. But that cost me also a few hundred bucks…
I think EFI-2T have only to downsides: higher retail price and more weight! Everything else will be a step forward.
I think people drastically over exaggerate the issues with jetting a carb. It's one of those running internet truths that just keeps getting passed on and amplified, to some extent. Also, one could say that KTM's track record with the Mikuni settings might be an indicator of the stock EFI settings on these new bikes! Same folks doing the the work? Hahaa
I wonder if KTM is going to spec only certain injector-approved 2-stroke oils for these bikes like they did for the TPI bikes? Anyone got experience running Castor 927 or Klotz through an injector? What happens when you want to raise compression, run high octane leaded fuel, share a can mixed at 32:1 with your son on an 85? Good luck with your locked ECU.
At the end of the day, I see the 250/300 EFI as pretty cool for the same old guys that buy an FE and put on cone valves and a Vortex and then sit in the pits admiring it over beers after 3 hard laps. And that's fine. The 125 is a little more baffling. 10 pounds on a 125 is not cool at all. That thing better be an absolute rocket, like head and shoulders better than the carb bike.
Bro, have owned a Mikuni SX? The first 2-3 years the 125 was unrideable stock and almost impossible to jet. You had to change the slide and the whole jetting including the needle jet to get it running right.
Since the oil’s diluted in the gas, there won’t be the need for special oil.
The SX125 is back to the weight of the YZ125..
What a disaster the mikuni was, great carb with bad settings that couldn't be jetted out. By that, I mean adjusted with just pilot, main and clip and not swapping slides, nozzles and all that.
Yes, I have owned many Mikuni's on many bikes. No issues once jetted correctly. I'm sorry you had those problems. I guess you never found the KTM Mikuni jetting thread with simple solutions here on Vital. Also you'd see my posts all over it showing my TC125 rips with the Mikuni and does not require re-jetting over broad temp and elevation changes. Changing a slide is cheaper and easier than buying a new re-mapped ECU from some high priced tuner shop! hahaa
It's all good man. I hope these new bikes rip. I certainly won't be a first year buyer. Maybe year 2 or 3 if they just kill the carb'd bikes. And Ten pounds on a 125 is not cool, no matter how you say it!
Oh no, I used the thread and did all the stuff. It ran good! I just found a cheap used Keihin and put it on the bike. I like it more than the Mikuni because it picks up better and has a better response from quarter throttle. And it’s still less sensitive to temperature and altitude changes.
No question: 10 lbs is a lot (or too much) and it’s a little sad that the bike goes from crazy light to light.
If not, for the life of me I can't see why the 2 stroke SX system would be locked.
Both types are Off Highway vehicles, not subject to any EPA rules, as far as I know.
Pit Row
Been running klotz through TBI snowmobiles for over a decade, their snowmobile and jet ski blend are injection specific. I run klotz Even on high boost 200hp+ modified sleds, I often use the Mx blends when I’m out of their sled specific blend. I’ve also dumped blends all and 927 in before also, never any issues. In the sled world you have to run aftermarket fuel controller “box” when going to high compression, and in some cases even when you add a pipe. The snowmobile fuel management systems are a bit more complex but have locked ecu’s also. Get expensive in a hurry, but they also run very very well stock.
I’m planning on buying a 250sx but will be keeping my carb’d one as I expect it to take a season before I get the new TBI working how I like it. I’m going into it knowing I’ll need a remap or aftermarket ecu. Locked ecu’s are kind of ridiculous on a closed course race bike IMO.
I think itd be cool if they left the gas gas carb’d but gave it the chassis updates. They’d have all the user groups covered that way.
It's strange that other manufacturers haven't a set up like Yamahas Wi Fi phone tuning app. Yes, most other companies set ups allow tuning with Plugs, or via computer, or KTMs bar mounted unit, but nothing is as simple, or as free as Yamahas set up ( which I know has limits - but I've ridden them with a variety of maps, and it's amazing the changes that can be made).. Perhaps, somehow, they've a patent on it, but I've not seen such a claim or notes on it being so. Weird.
I'd guess companies like JD etc will come out with 'piggy back' modules, and, of course, companies will be doing complete ECU replacements.
I will say, I see EFI as more of a natural fit for 4-strokes than for 2-strokes. The carbs on 4-strokes were a lot more complicated and difficult to work on for the average guy. 4-strokes have more compression and are more difficult to start, EFI eases that. 4-strokes have the engine braking issue which can be tuned to suit with mapping. Electric start is a godsend on a 4-stroke, so you already have a battery there.... None of this applies to a 2-stroke, so not exactly an apples to apples comparison.
That and spooge on the silencer. I will say that the Zook is still F A F!
However, only IF done right.
Did people bitch and moan with the introduction of the Reed valve?
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