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This sucks… someone at KtM reads these boards…. C”mon man… totally unacceptable for a brand new bike…. 10hrs on my 300SX, no issues and runs strong. Hope KTM gets the 125 sorted for you.
Thanks man, I appreciate it. It will work out-
Soggy, do you accept dm's? I tried but I think you blocked me lol.
I’ll have to check. I’ve never looked since the site was updated. I don’t block or have anyone blocked so that’s not it.
update yea apparently I had them turned off. Didn’t even know that was a thing. Haha
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Hi guys,
Jbone, thanks for your time in the informations.
Well, if I understand, there is no way to modify the injection like on the 4strokes, that means we could easily end up being too lean or too rich with those bikes by just changing a pipe for exemple?
They seem not to appreciate when we wanna "work on them", maybe something got messed up when you took off the reed cage and did the V Force video?
The only reason there is a way to tune the four strokes is because aftermarket companies made ecus to do it. It will take the aftermarket some time to come up with an ecu and tuning. I have heard maybe the tpi and tbi bikes share an ecu. If so that will shorten the time needed to develop something.
The oems don’t want you messing around in the ecu because they think you will shorten the engine life. Ktm has a history of covering things months and many hours after sale. Locking the ecu gives them some assurance that an engine that blows up with 10-20 hours on it was probably their fault and not yours.
Thanks for posting-
The stock ECU is locked so making any changes to the architecture of the mapping can't be done, for now :-)
The sensors on the bike do monitor AFR, air temp, etc, so technically, it self adjusts and the only way to make it lean or rich is to change your fuel/oil ratio and octane, which I do not recommend you do.
The pipe is post combustion and shouldn't have a huge effect on the lean/rich AFR, the pipe mostly just shifts the "hit" and some do add some HP here or there, but it is more of a tune change than anything else.
I don't think anything got messed up, it is a direct swap as far as the cage and gaskets is concerned, it only goes on one way.
What I think is happening is since the VF reeds are thicker, they require more draw/push to open at lower rpm and starting over the thinner stock reed petals which are easier to open. So to get it to work a bit better, I advanced the idle a hair, but this does effect the TPS so I had to do a little dance with the red idle and TPS to make it idle correctly and feel snappy. It sounded great, snappy, barked, but I had a non related engine issue that forced me to start at the stock set up to figure out what was going on and I haven't been able to get back to the dyno yet.
I feel that it will get sorted.
J
Great points, we will see!
Heading to the dyno soon after the holidays.
Good luck JBone, hope this all goes a little better for you
Thank you. I really need another 125 to test back to back so rule out anything with the dyno.
however I have 1000’s of pages showing good and typical dyno runs.
Wmr is now claiming they are unlocking the ecu and mapping and dyno tuning bikes. Do i believe it no but that’s what they claim.
Yeah, I have been talking with Joe Brewster for a while about this as well as a future plug in tuner to the access port to clear codes and load maps down the road.
$500 for an ECU retune however, if you take your bike to the dealer afterwords to get a code cleared, the KTM XC_2 tool may auto flash and revert to the previous map and wipe out the cracked one.
So i figure i owe it to the WMR guys to chime in here - I actually took our bike to WMR last Friday to try their map. Our bike was so bad we weren't going to be able to race the Winter Am's this coming weekend so i had to try something. I can honestly say from firsthand experience, they're not bullshitting. They have it figured out. At least they solved our issue.. We can actually use both maps now and it completely solved the bogging issue we had. It was a massive difference and really woke the engine up too. I'm praying to God that we don't have to deal with what J-bone is saying about it over-riding it when hooking it up in the future...
They did their map and had my son go test it by doing a few starts and just ripping it up and down a little stretch of grass by the shop. It was better but when you brought the rev's up and held it for a few seconds (to mimic a gate drop) it would start cutting out. Not as bad as before but still just a touch off. They took it back in and tweaked a few values and had him test it again. It was such a massive difference that before my son could even come over to give his feedback, you would have thought the WMR guys just hit a walk off homerun in the world series and we could all see how relieved my son was from 1/4 mile away.
They were going to dyno it before and after but we are a few hours away and they were cool enough to squeeze it in while we waited so for the sake of time we tested it that way instead of the dyno. Frankly I'm glad we did it that way because the dyno would not have picked up the little bog on the starts. Today we took it to the track to truly put it to the test and it's way better.
Thats great news, glad it works well for you guys...I emailed you just now- J
2-slow MX: glad to hear people are getting into the ECU and getting real results. Sooner or later, KTM will have to concede and give the consumers a green map that works along with improved fueling in both maps. It seems like KTM did an ok job on the ECU settings on the 250/300 but missed the mark on the 125. Hopefully over the next few months we see tuners offer reflashes to bring the bike up to where it should be. Thanks for reporting and good luck at the races!
For sure!
From a principle standpoint, I would just like mine to work and run as intended, designed, marketed, and advertised and I don't feel like I (or anyone else), should be the test subjects and spend more money, (on already the most expensive 125 dirt bike made), to get a bike re-tuned. It should be good to go.
This is not an unreasonable request.
Good luck!
Completely agree with you here. I'm furious that I am having to pay extra just to make a machine work as it was intended.
Pit Row
That is great news! Funny how WMR needs two month (Or less) to figure it out and KTM has had I'm guessing a year. Glad to hear this is moving in a positive direction.
...and didn't touch the mapping. Interesting.
Interesting. Seems backwards to modify the engine to alter fueling instead of first optimizating fueling to see what’s there power-wise in stock form. Lol. I can’t wait until someone produces a tuneable ECU so we can see where the stock power should have been. I have multiple friends that rode the preproduction ‘23 125sx and said it was amazing.
Something went wrong during the test and production stages for sure bc if you look back at all the video stuff from this summer they all said they ripped.
They've set them up rich so people don't blow them up.
Also, on the fueling, jd jetting has a piggy back setup for fhe 250,300. Decade old technology that people ran on the original rmz450 from 2009, before people could map oem boxes or vortex were available.
Getting any where with this jbone?
No.
Supposed to dyno another 23' 125sx for a comparison soon, just waiting for the bike to show up. If it's low, we'll know.
I have a decent theory as to why things ended up the way they are and some of it has to do with the 22' 125sx crank/ECU nightmare, and a host of other small things that are plaguing this model. A comedy of errors from the mis-printed manual, to a production issue, etc. It's a few things.
I'm going to give it another week but if no new map/ecu fix happens by then, I have to escalate this. I don't want to but I can't see my and many other holding the bag on this and paying for it.
The are making the 24's right now, but with this same ECU and mapping? I don't think they can since these aren't selling and safety is a concern.
Thx for asking- J
ECU has an estimated release date of 3/27 so I ordered one up.
Its a long shot but there could be some changes to the physical box that they changed that may make the ECU work.
FYI- with ANY 2023 model Ktm both 2/4 stroke you will need a valid VIN to order an ECU. This is so they can data log it in the computer and assign it a static number that when they push the proper mapping for your bike there is a digital handshake and it will take.
Thanks for keeping us posted on all this. I'm going to look into this
Cool.
It's a long shot and probably won't work but if it doesn't then I can say I ruled it out.
*ECU CRACKED*
I will have an update and some tech info on the performance improvements for the 23’ 125TC/SX Soon.
It’s still cold and snowing here (CT), but as soon as I can get to the dyno and pull some numbers, I will.
The current direction of the mapping solutions was to make the white map have a nice solid pull all around with good over rev, and the green map usable with a mid-burst and the PV opening a bit later in the rpm range.
This as well as knowing a pipeset will be on it as well as reeds and a head mod and T2, to increase compression and take advantage of the modifications.
it still may be a little bit before the report back but that’s what the latest is.
More soon, stay frosty- jb
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