This started a couple weeks ago. It would randomly “bog”. But in reality it seems fuel is cut off or electric stops cause all I got for a moment is a dead throttle. I’ll check stuff and it will go away for a ride or 2 but come back. Last night it completely shut down going over a 70’ double and I rode an endo down. Scared the crap out of me. I have to figure this out and find the issue, I’ve lost confidence in this thing. I have a thread at TT, reached out to multiple YouTube’rs, found a thread her last night about wiring harness, so reaching out for suggestions here.. I don’t think any codes flashes, or at least aren’t. Could blink while happening, I just don’t catch it. I have a dongle but my apps/or Bluetooth obd2 just isn’t connecting. I have a small track and ride several times a week. I don’t trail ride, so this is happening on a jump filled track and I’ve had it with trial and error trouble shooting.
things I’ve done..
changed plug, old one was perfect color
reset bike by unhooking battery twice
reset power valves twice
set tps to .400
changed inline filter twice
pulled fuel pump, took pickup filter off and inspected.
checked wiring harness for shorts wile it was running
I’m going to take tank off and plastic and really look at the wiring harness after reading a post here, plus check head bolts(user suggestion here)
I have a new pump pick up filter and a ccps coming, but I just don’t feel it’s those things. At this point I need a definitive “that’s the issue” discovery for confidence.
The above pick is of my old filter, new filter, and a plastic wire sheath that fell off the pump wile i was changing filter. It must be dissolving. The old filter is kinda black.
My guess would be CCPS. Try cleaning it with electrical parts cleaner or swap with the one hidden under the left side cover above the fender.
So I took it off today and tube and it was clean. I have a brand new one but haven’t put it on. My issue seems like it’s not the ccps. That seems to affect idle and low rpms. Here’s pick of my ccps and tube from this morning’s search for issue. Im currently riding (taking break) but kinda staying off my big jump. Trying to get it to do it some more.
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Posting that pic of my cups above I noticed the foam seal looks tore and maybe not sealing good. I may go switch it with the one under seat.
I’m going with pump, big fuel filter, or ecu. Have you ran it since you changed the big filter?
I rode for about an hour and a half yesterday, no issues. But it could go a couple of rides without doing it. I ended up changing the ccps too.
do these have a roll over sensor? Can I bypass it?
On that CCPS sealing ring... in the FB forums all the experienced guys add additional sealant on that thing to make sure it is not sucking air or leaking.
I may do that, actually i will do it.
This is what JBub said in a post in his FB TBI group for what sealant to use - "aquarium grade clear silicone or HondaBond is good". IN any case, you'd have to use something highly gas/oil resistant. Maybe Moto-Seal would be good also.
If you're not in the FB groups, there's tons more info for the TBI bikes there. https://www.facebook.com/groups/709915283880183
Thanks for the link, i dont have a facebook account but was very interested in reading issues like mine. With is with the 2 strokes? That dudes shoulder X-ray that crashed because of the bog on a jump is terrible looking. I rode about 1.5 hours yesterday and about 30 minutes this morning with no issue but every time i come up to my big jump ramp i am praying i keep throttle.
Read the comments on that xray post. Many others with similar issues. Many other posts as well. I have very strong negative opinions about these TBI bikes. I'll just say I'd be riding a YZ before I'd get one. And that's coming from a guy with 3 Austrian bikes at the moment.
I did. Not super pumped about it. Looking at a 350 now, maybe 450.
Wonder if the tip over sensors can become an issue?
Totally agree with you, when i read all this about the TBI Bikes i will keep the carburated Husky 300
This comes from a guy who had 6 of the Austrian Bikes
Today i was riding, bike runs great, great throttle response, feels, (this is about 3 or 4 rides since i last posted…. Took a break and began riding again. Bike starts to feel what i think is a little lean. The flicking of throttle makes just a subtle “ping”, thats the best way i can explain it of idle throttle blips feel more like on/off button instead of a good smooth throttle. Bike is good and hot too. I was starting to get low on fuel. It didnt really bog but it just wasnt feeling right. Fuel light finally came on and i went to the barn.
Is it possible for it to start running lean as fuel gets low? What is the mechanism for fuel mixture? An O2 sensor? Could fuel pump be mixing air in fuel when low? Could fuel pump have a leak that shows up when fuel level is low? Hate to just change the fuel pump but might.
This has the tank with the extra sump hanging down low, right? There is a known fuel pickup issue with those. Since the fuel pickup point is in the middle of the tank on top of the frame it relies on the fuel splashing up there to get to the pump. So, yes, it seems plausible it could be intermittently sucking some air when the fuel gets lower than that pickup point. Guys who ride these offroad have realized this is a fuel range issue. The bike can die when it still has plenty of fuel down in that sump if you are riding on really smooth terrain, like a fire road. Rough terrain helps splash the fuel up to the pump. Some guys will occasionally pop a wheelie to get the fuel up to the pump if they are riding a smooth road trying to get back to the truck.
The tank is really dumb. If you pull the pump and look at the design, popping wheelies doesnt do anything, the pickup is shallow and going horizontal it just spill back in wings. Really is dumb design.
Pit Row
Just did it again. 3/4 tank, running it hard for 40 minutes. Bogged and sputtered right in the air on my 70’ double. Must have hit it 25 times this afternoon. The dealers “ktm guy” is supposed to be back from vacation, will try and get it in. I don’t for see any solution from their diagnostics.
Update..took to dealer to get map updated, tech doesnt know if it was the same or not as ktm doesnt say.($130)
reached out to ktm and they said to do a top end and clean power valves cause it way over the limit, manual states 15hr for top end….yea, i know. My bike runs dirty, and the tech made the comment that not all bikes run the same, meaning he pdi’s a ton of them and there are little variations. Some run clean and some run dirty imo. My bike probably has less a chance of grenading than a clean/leaner running bike. Some of the power valves i see online are almost spotless at more hours.
What fuel, oil, and ratio are you using?
I don’t think the top end is your problem…100hrs on a 300 top end with proper maintenance is normal..If the new top end service does not solve your problem. I would start swapping parts with a known good runner. Ecu, map switch, start/stop switch. do you get those switches wet when washing? I don’t spray water directly at those switches, just lightly clean with damp sponge. Tank venting good? Try another cap? Have you removed stator cover to inspect? Maybe something loose or frayed wire? Pull rear fender back from frame & look to make sure no crimped wires, I have seen air temp sensor & tip over wiring crimped between fender & frame. I never experienced what you are on my 23, but did have a stumble when getting back on the throttle hard after landing from jumps, I had my ECU remapped by John Ross and it solved the problem. These bikes don’t like to be free rev”d while in the air, rev limiter kicks in early with no load. Just throwing some things out there for you…
Just to answer, I’ve stripped bike down and many, many things. I agree the compression was still at 196, but my power valves were dunked up bad. Maybe too sticky for the servo? I stay on the pipe quite a bit too. Like I’ve said bike runs great, but that bog…or could even be described as a stumble, is too dangerous on jumps. I need to figure it, but probably won’t because it’s probably an ecu glitch that just can’t be done away with. If I just rode woods it would be fine. But my little track is just jumps.
60:1, moterex with pump. Always fresh, but just found 93 octane non ethanol fuel. So will try that..
People are having issues on the r strokes also, just wierd stuff like bad harness, wires rubbing, bad sensors, corroded swtiches and buttons etc.
The ktm bikes since 23 have been iffy imo
Always, ALWAYS, get easy clips!
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