Posts
4
Joined
9/6/2023
Location
Blue Ridge, GA, USA
Edited Date/Time
9/12/2023 6:34pm
Hey guys,
I have two 23 KTM 250 SX, (fuel injected) both have right at 30hrs, did top ends on both bikes.
Bike 1 - after top end, bike was bogging and doesn't want to clear out, started searching the forums and found out about the dongle (no one told me - you'd think the dealer would mention this) anyway it runs worse after the Dongle PW reset procedure) bogging bad in low to mid range
Bike 2 - bike running good, but not sounding fully clear. Ended up changing the start/stop switch. Fixed.
Reset powervalve in both map modes? Inlinefuel filter replaced? New spark plug? All wiring connected properly? Running good before top end serviced ?
Thanks for the suggestions, we got it fixed. Bike 2 . Cleaned and greased every electrical connection, changed Start/stop switch - All Fixed. Should have started there first but have piece of mind going through electrical and greasing everything anyways : )
PS - still investigating Bike 1, it has the aftermarket Nihilo start/stop switch. Bike 1 is next, going to change plug, check all electrical, change fuel filter. Bust next few days get to it this weekend.
Thanks!
Post up your findings on Bike 1 once you figure it out.
Does it run like this? I’ve been chasing this for 12hrs. Tps dialed. Both dongle resets done many times. Swapped CCPS. Good fuel pressure. Good compression. Runs with battery unhooked(good capacitor), remapped(twice, John Ross)
I have the Nihilo switches and need to try my stocker to rule it out.
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Have you tried a new plug & in-line fuel filter? Check wiring to air temp sensor, some have been unplugged or crimped by rear fender. The cold start/ choke is supposed to snap back to off position when rolling throttle forward, mine stuck open a few times, had to manually close it. Does the bike run good under a load?
Bike 1- changed the start/stop switch on Bike 1 back to factory and it seems to be fine now.
Our bikes did not sound like the video above. Bike 1 was a smooth bog. (if that makes sense) about mid to high range- and Bike 2, just didn't seem to clear out completely sometimes, new switch fixed it.
I would go through all those electrical connections. And I would swap it out with the factory switch just to see if it makes a difference.
Sorry I'm no mechanic wish I could help more.
New plug, br8ecm, gapped to .23, has maybe 20 min on it.
Inline filter looks brand new, totally spotless.
I will check wiring to the air temp sensor.
TPS base set at .400v. Idle .500v.
Cold start knob functions properly and has been off.
Runs worse under load, up the street it runs fine. I ride woods, it bogs so bad it’s not worth riding. Someone real slow and doesn’t put a load on it would probably not have a problem, but trying to bang it up with other A class racers, forget it, sounds like it’s about to foul a plug but the plug reads that it’s running well.
Just throwing things out to try…I have 60hrs on mine, never had this issue…I have mine mapped by John Ross also. If stop/ start switch has no effect, I would test stator…
There is also a fuel filter in the tank. Need to check that too.
Have you considered taking it to the dealer and having the latest map update installed and have them check all the settings to make sure its set to factory recommended spec? I'd also change the in tank fuel filter.
I have the latest John Ross map, he’s remapped it twice.
Oh ya, I pulled it, it’s spotless and flows freely. I get a consistent 50psi of fuel pressure.
I have aftermarket mapping, it was just updated 9/1/23. My tps is set at factory spec, I’ve set and double checked it, .400v base, .500v idle which is Ktm spec. I pulled and inspected the tank fuel filter, it looks new and flows as it should, I get a consistent 50psi of fuel pressure.
Has it been this way since day 1 or did it come on after some hours?
IMO it’s ran “soft” since day one, fouled a plug at 9hrs and have been chasing this bog since about then also. First remap at 11hrs, second at 17hrs, has 20hrs now. Plug looks good, before the remaps it was always nasty goopy black.
PV may be sticky or stuck, ECU might be bad, injector might be bad/plugged, coil might be weak although the plug looking clean probably rules that out. Is the battery voltage dropping when it does that? It might tell you if something like the PV is pulling too much current because it is stuck/sticking or if the stator is weak. It sounds like is isn't getting enough fuel though.
PV moves freely and is clean. PV motor visually looks ok.
I think the charging system is good, I pulled the ground off the battery while it was running and it still runs fine.
The kicker is that I can ride it up the street and it runs pretty good, jump on singletrack and it falls on its face almost instantly. I’m almost thinking my TPS is bad and the quicker throttle movements on trail make it act up? Seems like a logical guess to me? Need to hook it up to my tps tool and see if get any strange numbers when cycling the throttle.
Check the wiring under the regulator/rectifier. I've seen pictures where those wires were rubbing on something and you could see copper showing on some of the wiring. I've had my bike remapped by JR also. This is my second map by him. I have a 23' 250xc. I've been having an intermittent issue with a lean bog after riding for several hours with no problems what so ever. My issue happens late into my ride when I've burned through half a tank of gas or more. I recently replaced my in tank fuel filter. I'm starting to think its the fuel pump because my bike starts acting up when the fuel level gets 1/2 a tank or so. I'm almost to the point of taking it to the dealer and having them flash the latest maps onto my bike just to see if it makes any difference. Overall I haven't been super happy with my aftermarket tunes.
Pit Row
I've heard of guys going to a br9 plug with good results. Worth a shot for 7 bucks
TPS will affect fueling so will some issue with the fuel injector (unlikely) or the wiring (more likely).
Another way to look at it is if this bike had a carb what would you change to try to fix it?
The 250 & 300 both come with 8 heat range plugs, some run 7’s but I personally would not. The 125 runs a 10 and some run a 9.
See if you can get JBonemotorworks on this site to take a look at your video. He is pretty knowledgeable about the new KtM”s… I have spoke with John Ross about the bikes computer, ability to continuously learn values… sometimes this has to be cleared by the dealer, it can be done without wiping out your mapping.
We have been talking, trying a few things, strange..Im calling a sensor or electrical issue with harness etc.
Figured you would be in here sooner or later. It’s a downer when your new bike is not running correctly… and nobody seems to have an answer. I would try to find someone with a 300SX that is running good & start swapping electronics…or bring to a good dealer to have them take a crack at it…
Suspensionguy - I really hope you get this figured out. Our bike 1, had a smooth bog. (I say smooth because the bike in the video above sounds yours sounds so choppy) just did the reflash of the ECU at the dealer yesterday and both bikes are running perfectly.
And again, the start/stop switch fixed it.
I'd try a wiring harness swap. We had friends with a 22 gas gas 125 and they went through several harnesses...🙄
Suspensionguy- any luck getting your bike to run better?
Not yet, I took off camping for a few days. Going to check all the writing and put my stock start/stop back on.
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