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No wonder people were upset with these bikes. What a poorly tuned piece of shit. At least the aftermarket has proven these bikes aren’t destined for the scrap pile.
If you watch that video some bikes would put out that low line and some would put out something closer to the GET line. There was and maybe still is a huge inconsistency between individual stock bikes.
We had a 23, 12SX. I’ve been involved with racing for 45 years and I thought no problem . That bike virtually made me contemplate suicide a few times. What a turd . we got rid of it and bought 2, yz125s. Lived happily ever after.
If I had to do it all over again, I would get the TSP kit. Gives you the ability to clear codes on your own ,change jetting and timing. Plus, it comes with a head that’s cut different and with different compression. I think that is key to getting those things running better.
I know there’s Ktm 125s out there that run good. It was just so hit and miss. Today it would run good tomorrow, It would run crap. Constantly fiddling with sensors and resetting throttle position sensors.
If it can't fit a Boyesen Rad Valve in the motor...it aint a real 2 stroke.
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are you looking to sell that husky? I PM'd you
I know a moto dad that got his boy into top 3 Ponca Nat starts against top riders with fully built 125 engines. All he did was swap in the STIC PWK Super X carb onto a stawk '22 125SX with pump gas. Imagine that on your CR's.
I took a chance on a '24 300SX WMR re-flash and PC Works pipe and was enjoying the best bike I ever rode. Regrets, 60 hours-ish in and she won't start. Too busy, so I'm slowly working thru. troubleshooting. Gonna have to buy an OBD2 analyzer and the adapter I guess.
Glad I have my ballistic STIC PWK equiped 200SX to sharpen my skills.
While the tech is nice on the 2 stroke Austrian bikes personally I'm of the carb persuasion...hell might as well nix the the e start too. That's the beauty of the simplistics of 2 strokes. YZ125 for me brother...
125/150 are very sensitive to tuning the stock reflash helps from a reputable tuner. The GET is a huge improvement.
My local MX dealer Privateer Connection in Rock Hill SC has spent extensive time tuning the ECU while on his dyno with great early settings on the stock unit. Fine Tuning on the dyno will get even better performance.
He also mentioned that the top end needs to be fresh and replaced often to keep compression numbers up. When worn and the Compression drops and the ECU does not self adjust like the vacuum carburetor does.
Was that result from HP guys down in texas with just the ECU or did they port, polish and mod the squish at all? 🧐
Has any one tested the MXA claimed Scalvini Exhaust by itself themselves?
Here are the claims: https://motocrossactionmag.com/mxa-team-tested-2025-husqvarna-125-150-s…
After a lot of testing on a 2023 TC125 in stock form in the PNW, I have found it’s slow. Lol. However, its still fun as long as the track is relatively flat (On city style arena type tracks like Pacific near seattle. However if you take this stock bike to a track with real elevation changes (Washougal, CMX, Ward Creek, Glen helen) it is extremely bad. The gearing vs rev limit is a mismatch. On flatter tracks the RPMS can barely get to the next gears hand off point before the rev limiter kicks in. Race conditions up hills you’re totally screwed.
Essentially, it feels like they left carb gearing in a bike that has a rev limiter that cuts off the RPM’s before the next gears hand off point. Thats the real problem with this thing. If the Scalvini cn offer some additional over rev it might make the bike somewhat rideable at a track like Washougal. If the HP numbers are correct, then the bike might actually be vaguely competitive on a track like washougal. But probably not in an advanced class where all the guys know how to race a carb 125 well (top 5 to 10 guys in the 125 dream race of any age group would put a ruthless beating against any near peer on this bike). If the numbers from HP are correct, then It might be somewhat competitive and maybe even an advantage on the true 125 novice level where the guys who aren't seriously sand bagging are just learning to ride a 2 stroke 125.
If any one has tested the Scalvini or HP’s GET ECU mod, and have managed to overcome the terrible RPM vs Ground speed vs Gearing hand off on a true national track. Please let me know. Its basically just a fun and somewhat safe bike for beginners to to ride in its stock form.
I just got an 18' 300XC, swapped it over to a Keihin PWK38 and it runs great. Still got some tuning to do and parts to order. Compared to my old mans 24' 300 I'd say the carb version is a bit more peppy and erratic. The EFI is smooth and powerful. I wanted to try it with the TSP tuner and see how it felt after that, I imagine its about perfect.
X2. A 125 is small and lightweight, where the kickstart is easy and carburetor adjustment is simple enough vs e-start and ecu weight. In other words the light weight and simplicity of the 125 outweighs the need for extra weight and maintenance (for me). Now on a bigger bike (like a 300) I could see a benefit of the other stuff.
There is a needle tapper that mimics that linear trait of the FI. Search the jetting forum over at ktmtalk.
If the question is whether a 125 should have been made EFI at this phase in development, the answer is absolutely not. My question is how to fix the 125 EFI problem I have without tossing the efi into the lake. I also have the same year TC250 and EFI is awesome on my 250 2t. It has enough motor to cary it between gears with a rev limiter. A 125 doesn’t. The problem is, they have put a rev limiter on the 125 that cust off before it is ready to hand off to the current transmission gearing (which the gearing was designed for carb bikes with over rev!! Not for EFI with limiters). There’s 2 ways I see to fix this 125 EFI problem: 1. Raise the RPM limit to where it can hand off the power in shifts between gears (probably the simoplist fix) 2. Change or lower the transmission gearing to accept the hand off at a lower RPM… this would require also adding at least one gear to span its way to the upper limit for a standard 125. KTM seemed to believe people could just cover the hand off of a rev limit vs gear mismatch with feathering the clutch. Well, that bandaid works sort of if you don’t mind replacing the clutch every moto lol. Again, this is not a problem on the 250 and up bikes. They run fine if you’re not completing in the world 2 stroke race at the top level. Theyre a great open class vet bike. The 125 is the problem Im trying to solve, not the 250 or 300.
People like to say a pipe ads overrev, but I don’t see how any pipe is going to literally increase the rpm’s on a bike that has it’s rpm’s hard limited by ECU mapping.
Fwiw the ‘25 TMs come with either a carb or Fi.
Pit Row
My 250 tbi is substantially quicker than my yz250 was. I like both btw.
Careful, the Austrians rather than fix a crank, they went to a rev limiter. No more warranty claims...all fixed.
You need to sell that 125 to more of a casual rider. A bike for the whole family.
Post a reply to: Can we talk 2 strokes , carbed and EFI for a minute?