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Discussion Starter #1
The RPM is steady around 2000 and then suddenly stalls. haven't had this issue before and my ODO is at 26000KM. started happening like a month ago. the only change I have done is change my spark plug and they remapped my ECU for fuel and air mix for the new muffler. that's all. Does anyone know what's happening?
 

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Well in my view, if this occurred after the remapping and the spark plug swap I would start by returning the old (or same brand and heat range) plug and test it for a week.
If the problem persists I would have the dealer put back the previous map.
A 390 engine at 2,000 RPM idle runs about 500 PMR too high.
 

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Discussion Starter #5
Well in my view, if this occurred after the remapping and the spark plug swap I would start by returning the old (or same brand and heat range) plug and test it for a week.
If the problem persists I would have the dealer put back the previous map.
A 390 engine at 2,000 RPM idle runs about 500 PMR too high.
They Adjusted the spacing between the sparkplug and man that made a huge difference on the bike starts up in one go and riding the bike on low RPM is way smoother. Before it was like jumpy when you riding on the same RPM... they also did an update for the remap and ask me to test it for a week. So let's see... I will keep you guys posted as well.
 

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They Adjusted the spacing between the sparkplug and man that made a huge difference on the bike starts up in one go and riding the bike on low RPM is way smoother. Before it was like jumpy when you riding on the same RPM... they also did an update for the remap and ask me to test it for a week. So let's see... I will keep you guys posted as well.
Curious to know more about the electrode spacing on the plug. please do share more on this and post an image if its available
 

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You can find this in the manual.
If the OEM Bosch plug is still in the bike after so long you probably will need to adjust the spacing according to the manual.
I have put a Laser Iridium plug (by NGK) in my 200 as checking/replacing the plug takes somewhat of an effort.
The Iridium plug should not be tangled with and used as-is.
It lasts 5x longer than the conventional plug though.

Curious to know more about the electrode spacing on the plug. please do share more on this and post an image if its available
 

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Discussion Starter #8
Curious to know more about the electrode spacing on the plug. please do share more on this and post an image if it's available
I actually forgot the mm gap adjustment they did on my bike... and also my spark plug is like 2 months old and I'm using "ngk lkar8a-9"

@KTMasean btw I just did a Cold start and the bike still shuts off... the weird thing is it runs steadily for like 5-10 seconds and stalls... after that no problem :( unfortunately, I do not have the old sparkplug to test it... will try a new plug maybe next week and see...
 

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Yes the NGK replacement plug for the OEM Bosch VR5NE is the LKAR8A-9
The iridium version is the LKAR8AI-9

In general, the gap of a new plug should not be altered.
 

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Discussion Starter #10
Yes the NGK replacement plug for the OEM Bosch VR5NE is the LKAR8A-9
The iridium version is the LKAR8AI-9

In general, the gap of a new plug should not be altered.
the NGK LKAR8A-9 plug is the standard nickel plating with a copper core. according to the KTM tech and the KTM specs you have to change the gap. and the required gap is 0.8MM for the duke 390.

Just a thought can a low battery cut off or stall the engine?
 

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Discussion Starter #11
Yes the NGK replacement plug for the OEM Bosch VR5NE is the LKAR8A-9
The iridium version is the LKAR8AI-9

In general, the gap of a new plug should not be altered.

Hey, So I figured something out. when I do a cold start I need to either sit on the bike or make it straight before starting it. and the no more stalling... only happens when I try to start it on the side stand or the bike is tilted on the side...

Engine Oil pressure issue?
 

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Hey, So I figured something out. when I do a cold start I need to either sit on the bike or make it straight before starting it. and the no more stalling... only happens when I try to start it on the side stand or the bike is tilted on the side...

Engine Oil pressure issue?
I would say fuel pump issues... maybe not the pump itself, but something within the fuelling circuit...
 

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Could also be a faulty drop-switch.
there is a safety switch that kills the engine when dropping the bike.
Difficult to say from a distance, really.
 

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Discussion Starter #15
Weird and a hard thing to figure out right now... I did a test yesterday keeping the bike straight up and left the side stand down and the bike stalled...

I have been talking to the KTM guy and he also checked everything also the side stand switch he couldn't figure out. Should I go ahead and just change the side stand switch to test it?
 

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OP, my bone stock US spec 390 with about 11,000 km on the clock has a quirk similar to the one you've described in that it occasionally stalls a few seconds after a cold start while idling. This usually happens while I'm waddling backwards out of my garage, and never happens after I've set off. The bike has never failed to restart after stalling.

I have noticed that this stall only occurs if I have the transmission in neutral; if I have the bike in 1st gear and have the clutch pulled in when I'm manuvering out of the garage, it never stalls. I always chalked it up to a combination of cold viscous oil, and the tiny bit of extra drag on the engine from spinning the transmission by leaving it in neutral with the clutch engaged. Maybe try keeping the clutch pulled in for a little bit after a cold start and seeing if if it still stalls? I'm now curious to see how this would effect your issue.
 

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Discussion Starter #17
OP, my bone stock US spec 390 with about 11,000 km on the clock has a quirk similar to the one you've described in that it occasionally stalls a few seconds after a cold start while idling. This usually happens while I'm waddling backwards out of my garage, and never happens after I've set off. The bike has never failed to restart after stalling.

I have noticed that this stall only occurs if I have the transmission in neutral; if I have the bike in 1st gear and have the clutch pulled in when I'm manuvering out of the garage, it never stalls. I always chalked it up to a combination of cold viscous oil, and the tiny bit of extra drag on the engine from spinning the transmission by leaving it in neutral with the clutch engaged. Maybe try keeping the clutch pulled in for a little bit after a cold start and seeing if if it still stalls? I'm now curious to see how this would effect your issue.
awesome yeah, I will try this out and check it out. Thank you
 

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Perhaps this comes with the E4-5 emission control in having a bike run idle for an extended period of time is hazardous to our environment? :LOL:
 

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Discussion Starter #19
Perhaps this comes with the E4-5 emission control in having a bike run idle for an extended period of time is hazardous to our environment? :LOL:
hahaha! I don't leave the bike idle running for more than 5 mins in the mornings... I normally turn off my bike when I get stuck in traffic.
 
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