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These 2 strokes are strange all around lol.
Man after reading this I’m glad we still run our 2020. Between bad cranks and this efi shit I’ll stay old school and let Haeseker keep mine ripping.
He’s a good dude
Just installed my John Ross tuned ECU. Here is what I found on my powervalve recalibration.
1. my bike, 300SX does not default back to the white map. Just like my 4T”s it stays on whatever map you left it on.
2. set throttle at 1/2 way open as per manual. I just loosened throttle housing bolts, pushed throttle tight against bar end & tightened bolts, throttle now sticks where I leave it.
3. plugged in dongle to wake up ECU. Woke bike up, but no Audible sound from powervalve. Waited 5+ seconds, nothing. Rolled throttle back to off/ zero opened. Now the powervalve recalibrates. Waited for it to finish, then disconnected Dongle. Started bike, rev”d out clean.
4. started bike again just to change map setting.
5. Repeated Dongle dance again. Unplugged dongle, started bike, rev”d out clean.
I will test out setting’s tomorrow. The manual states you should hear the recalibrate sound when you plug the dongle in with throttle opened 1/2 way, I did not hear the valve recalibrate until I rolled throttle to off/ closed position. No big deal but could confuse someone.
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Lmk how it goes, I noticed a small change as well with my 125 according to the manual but it works fine.
I hear one real fast “bizt” when I plug the dongle in…wait 10 seconds then let the throttle go and wait til it’s stops beeping and clicking.
good to go after that.
Stopped by the shop Saturday for some parts, and asked my guy about the 23 125sx. He said I'll give you a deal on the MC, but flat out said don't buy the KTM. Good enough for me. I was a first year buyer (2011) of the new 3.5L EcoBoost and that thing was nothing but problems. The Gen 2 EB has been much more solid, but has had multiple issues with the VCT setup, requiring 2 replacements at dealer cost. And it ain't a cheap fix.
New vid.
https://www.youtube.com/watch?v=nVaX6NcW76E&t=1s
A quick post. There is a series of “tables” that are related to each other, mathematically, that effect each other, and adapt to each other that related to ignition timing, fuel delivery and pv.
It is all based off the TPS and any changes to the engine (by use, intentional mods such as external TPS adj, wear and tear etc), and the tables attempt to compensate for these changes automatically, they hold their value, and sometimes for the worse.
Simply put, if you log 25 hrs on your top end, at some point during those hours, the wear and tear has effected the cps and changed the pressure under the piston, this has effected the way your ride, it made more heat, all the while the tables morf to attempt to compensate what it can to get it back to what it considers it’s zero point.
The tables shift and hold onto that value, it has “adaptive learned”.
You put in a top end and leave all as is, the ecu may still consider it’s held values it learned..this is why it is so important to clear the adaptive shift and get the engine back to its electronic zero so it’s baseline is restored.
This process to me is more important to the pv reset or anything else at this point.
The changes it morfs to can never go to an extreme and eventually it hits a wall and can’t move any more.
This is where if all those negative engine attributes stay held, the performance gets worse and worse.
The ex) of TPS adj has now changed my mind about how it is done.
If the TPS is adj, you are shifting the table of timing, fuel and pv, they are connected like a chain.
In very small movements, it will only effect the tables slightly, however as the engine started to wear down, the morfing gets more pronounced and “held”, or remembered.
This is also true with the sensing capabilities of the engine, it has held values determined by the sensors.
If you go down the the line at 9am for mx practice and it’s 45 deg, go back to the truck and shut it off and leave it until 1pm and start your bike on the line, your motor held the 45 degrees and will run that way until it catches up with itself after it learns.
What I would recommend in this situation if it’s 1pm, start your bike at the truck and let it run and blip for 20 seconds and then shut it off…then go to the line.
Your sensors will absorb the new data that it’s warmer and adapt.
This is one of the tables that has an X-Y axis as in engine rpm and throttle opening.
All those cells have cross over points over certain rpm ranges that effect each other.
Move one area, it shifts the table to effect fuel, timing, pv, etc.
I’m just getting the hang of the cause and effect of this but I can tell you one thing.
As for the actual combustion process of a two stroke motor with a pv, this is super simple….same same.
Regarding the fuel delivery, pv, timing, tps, crank pressure, etc throw everything you consider the “same” as a carbed bike out the window.
They are now two different things and should be treated that way, I have much more to share but am trying to keep it super easy to say and think about how to say it.
Stuff the cases with epoxy and dont compensate for that increase presssure under the piston with the ecu? It will also increase the velocity, lean out your fuel delivery and you will explode you motor..it’s that sensitive, unreal.
More soon- sorry if this is wordy, I’m learning and sharing at the same time lol.
Clear the adapted learned changes from your bike all the time and especially when large scale engine changes have occurred like top ends and if large environmental changes happened like cold am motos and hotter pm motos.
Great information! So what is the procedure to clear the adaptive value?
So far it appears to be the KTM tool at the dealer, however I recall reading somewhere about the dongle being used..trying to find this out now.
But, remember folks, jetting was too hard and EFI was going to be the great savior of the 2-strokes and make the thumpers obsolete!
If you took a ride on my 300SX, you may change your opinion..Most 2t guys like to tinker and learn. First year design, for sure some hiccups but it will only get better… especially with guys like JBone digging in. KTM is not giving up on 2t development, I will support them because of that commitment. I agree on the simplicity of the carb, my Vintage/ Evo bikes give me that itch to scratch when I feel the need.
I think the main problem is partly “us” trying to figure out and tweak a incredibly complex system based past yrs experience of normal two stroke info when it is not normal two stroke info with little to no guidance (except the manual), which is limited. There are also blatant outright things that complicated the issues with bad plugs, fuel pumps, cracking pistons, TPS failures , etc..
I appreciate your kind words, I’m just super into it, I’m not doing this for my job and just trying to find stuff out, share experiences and what I learn from others.
23’ and 20’ 250sx here, the 20’ runs stronger and the power is more broad. Sorry but these TBI’s don’t live up to the hype. And if you don’t like how they run you’re stuck, no jetting to tweak, no pv to adjust, no cheap way to swap cdi’s, not sure why having absolutely no way to tune it is a good thing or a step forward. The carb bikes were so easy to fine tune to the riders liking.
There are guys tuning the ECU “s now, I have my 300 tuned. The testing/ tuning is ongoing. I can’t speak for the 250 as I have a 300. Map 1 was rich/ safe tune, mellow. Map 2 was much better on an MX track but the midrange hit was hard and then it signed off a bit early. I put 30 hrs on it stock and now I figured let’s start the fine tuning. Ultimately I”m looking for a good tune in map 1 for GNCC/ woods riding, which has been achieved. Still working on Map 2 for Mx but it’s close. I have had carbed XC 300”s in the past that I was always playing with carb settings, seems like the 300 was a little more finicky to jet correctly, going from GNCC to MX.
I was able to get my 23’ tweaked with pv manipulation as well?
if you mean “on your own”, like in past yrs, for sure but there are solutions.. I don’t like having to spend extra time energy or effort anymore than anyone else does trust me, but I just looked at this as an opportunity to learn and have most of my crap together.
That's the part that gets me. KTM basically rushed these bikes to market before they were ready and they are using the public as beta-testers. It's one thing to mess up the stock settings so bad (same as they did on the carb bikes for years) but it's another to lock the ECU and force people to jump through ridiculous hoops and spend tons of money trying to find work arounds. It only takes a brief look at the 250/300TBI owners group on FB to see there are tons of probs with these bikes. KTM seriously missed the mark here. If these bikes came with a tuning app like Yamaha that allowed you to tweak fuel, ignition and PV to acceptable settings, they would have had a home run. Instead people are forced to drive back to the dealer and are strung along and stonewalled. Total BS.
Locally, I have seen too many folks having probs with the 125's especially. I've noticed the 23 GasGas selling much more than the KTM and Husky (won the shootout too) and I've seen some folks buy the new 23 TBI bike and then revert back to their previous carb bikes. And it's not just annoying, it's dangerous. There have been bikes cutting out on jump faces, etc. Unacceptable.
Agreed, I posted a whole scorched earth post in late nov of 22’ about it and kinda paid for it with certain people in that space.
I’m just trying at this point to gather and share info to try to get stuff sorted.
I’m not sure next yr I may be in for a new 24’ due to this but I know I will be ahead of the game for the issues if any arise.
Pit Row
https://www.youtube.com/watch?v=36LGWMyanyQ
Rev's to the moon!
Nice! Needs sand track test session 👍
I would like to ask if somebody has a solution for EFI error that appears after each bike washing.
when I wash the bike after a very muddy moto ... and I don't disconnect every single plug to clean it the error appear and I need to take the bike to the dealer for a reset ..
1) Why this happen ? the electronic is present now on our bikes from years and nothing like this happen ...
2) Why they dont give you the possibility to reset the error .. when you are on the race track you never know if your problem is solved or not ...
THANK YOU !!
What error code keeps coming back after you wash it?
Sometimes is the Basement pressure sensor, sometimes is the exaust valve...
I'm assuming you mean the Crank Pressure Sensor?
Cover handlebar electronics in Saran Wrap before washing, some state stop/start button is not 100% waterproof. most times I just take a damp sponge & wipe controls clean. I plug vent openings under seat before washing, Keep water spray below the seat. After washing I remove seat and dry up and any water that I see, air dry or let sit out in the sun with seat off. I have not had a single issue. I use garden hose most of the time for cleaning, pressure wash at the track and then I keep pressure washer spray very low, pegs, chain guides, wheels ect.
Great tips!
Do you think all the problems are depending from the handlebar commands ?...
I am using high pressure wash, and for long time ... as I made from the last 15 years in many different bikes ... no problem...
Anyone found an easy way to reset the errors without the dealer ?
Thank you
David
Fi codes are dealer only resets at this time.
Have an eye on the red OBD connector in the white plastic holder under the seat too... my friend´s 300 had water intrusion there and his map switch started to funk around like a discoball; since he discovered this he always takes it out after washing and blows it off and no further issues!
Think it was the switch or the port under the seat?
thx!
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