Re: KTM RC 390 Ownership Experience

New tyre set from appolo.looks good.
Check tyre thread for details.

Image is taken from tyre thread.

Re: KTM RC 390 Ownership Experience

Ignition coil, spark plug wire, relays, throttle position sensor are the other stuff that you can check.
if possible swap it with parts from another bike before buying new parts like the fuel pump etc..
also run a diagnostics check with the scan tool if possible.

Re: KTM RC 390 Ownership Experience

Intermittent jerks can be caused due to n number of factors, the basic being clogged fuel filter, less than enough fuel, gummed up throttle body and injectors. Now that, the run of the mill stuff taken care of. I'd strongly advise you to check how the bike behaves after the fuel pump replacement. Fuel pumps provide constant pressure irrespective of the engine RPM. If there is jerk above certain RPM or certain speed, it's advisable to check the fuel pump pressure, for the Duke 390 the pressure reading is at about 42 psi. Do keep your observations posted. If you still feel there is a jerk after the fuel pump replacement, it's time to check your O2 sensor/lambda sensor. A failed lambda sensor too can jerks midway as the ECU isn't able to adjust AFR accordingly and cause stalls.

Nonetheless, keep your observations posted.


Cheers!
VJ

Re: KTM RC 390 Ownership Experience


Will sure keep you guys updated.
The jerks and shut downs don't have any similar patterns actually

They don't do it at a certain rpm or speed or gear it's mostly random as far as I noticed

The first one that happened was a total shut down and denying to start up of the engine which happened after 6 minutes and a km

After that the next day I kept the bike on idle for 15 minutes nothing happened
Revved it alot and still was okay and drove it around for 4 kms and 30 minutes and was fine.

The next day experienced a shut down but started immediately on the first crank ( happened during the first 2 minutes) and gave 2 minor jerks during a 11 km run to the service center.

Following 2 days it refused to start had the fuel filter re cleaned and injector cleaned during these days along with cleaning of most of the connectors and cuplids

4th day after cleaning the throttle body started and was idle for 10 minutes in which the radiator turned on and off.

Took it for a test ride and filled the tank again it gave a jerk while the performance and vibrations had a day and night difference and was butter smooth cause of the cleaning
A friend took a ride gave him more jerks

5 minutes after that the bike was shutting down continuesly then refusing to start

At the starting it starts for a few seconds then when it's revved it looses power and shuts down continuing this it started for a second and shuts down without reviving it and then it resides to crank up

I can't find any pattern here as nor does it happen after a while nor does it happen when the bike heats up its randomly occurring
Happens sometimes in cold or a short duration while sometimes after a while and when the bike heats up

Going to get it diagnosed tomorrow and will change the pump with a friends ktm and see the results

Re: KTM RC 390 Ownership Experience

One fact about the highlighted part w.r.t to your post is, the fuel filter has to be replaced. The in line fuel filter that comes with all FI motorcycles are use and throw. They last a certain time frame (depending on the fuel quality). There is no provision for them to be cleaned. Once they are all gummed up and used up, it's time to for a new filter. Just in case, if you've been conned by any mechanic stating fuel filter cleaning, stay away from such mechanics, as it basically only worsens the filter and a waste of money.

If you haven't replaced your inline fuel filter, get your filter changed, and then check your fuel pump for the right pressure and how well the net inside the fuel filter is, if it's too gummed up and dirty, it's time to replace the fuel pump. Nonetheless, keep your observations posted.

Cheers!
VJ

Re: KTM RC 390 Ownership Experience

Anyone notice the rear portion. Specially the seat and plastic. Its not aligned properly. On left side you see its tilted upwards. Been like this since I bought it and even showed it to the showroom guys at time of purchase.

Re: KTM RC 390 Ownership Experience

At times, when I turn on the ignition I don't hear the fuel pump sound. I'm observing this for the past 2weeks, at least 3 4 times. I haven't noticed this before. Is this normal?

Re: KTM RC 390 Ownership Experience

Yes its the tyre hugger which hits the tyre more often so its normal don’t make the suspension/rear shocker stiffer as it will not be good for on road conditions..!

And for battery cover use a double sided tape ..!! or u can either replace it with a new one..!! I replaced mine with a new one for free cx i had the same problem..!! And now that rattling noise is gone..!! Hope this was helpful..!

🤜

Re: KTM RC 390 Ownership Experience

yea so went the other day to his workshop and tested my bike and it was working fine without any jerk, rode it for around 30 minutes in the heat but it wasn't giving any jerks and i got frustrated. As soon as i bought the bike back in the workshop it started shutting down on idle and would only stay on when the throttle is given. We immediately changed the fuel pump with a friends fuel fuel pump but the problem was still occurring. It wasn't giving jerks but was shutting down. So now as we had changed the injector cleaned the throttle body and pump all the fuel parts of the bike was changed so we figured the problem was in the electrical part. So we then changed this thing above the charger which connects to the spark plug wire. As the bike was heated up we acted quickly so that the problem could be identified quickly. But still the problem was there. Next he(the owner of the shop who looks after my bike) changed the spark plug cap an then the bike wasn't turning off. At first he thought it was because the bike might be cooled down but then i suggested to put the old one back in which was burning hot and the problem came back. Soo yea the problem was just a piece of connect which stopped working in heat and didn't send enough spark to the bike

Went to the service station and bought the part

Cost was around 160 rupees and its been a week and the bike performs well

The only problem I'm having now is that since day one the bike had enough pick up that i used to let go the clutch on 1st gear and it would ride without any throttle and the speed would be around 11-12 kmph but now if i let go the clutch the bike stalls and need a little gas or i need to let go the clutch very very slowly for it to work and that too the bike would run around 9-11 kmph with jerks. it was convenient at turns but now its different.
Any idea why this happened?

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Thanks that was the problem

Re: KTM RC 390 Ownership Experience

Thanks for the update. My general advice based on experience is that parts such as fuel pump, injectors, ecu, fuel filter do not conk out that often and it is always better to start off with smaller parts like i mentioned and preferably swap parts wherever possible before spending money and buying parts especially in cases where the issue is not very obvious.

Now that you have change the spark plug wire/cap , i would also suggest you check the ignition coil (that is where the plug wire comes from).
Check your chain slack and clutch free play adjustment - adjust them to spec. As you mentioned the bike should move when in first gear and by just letting the clutch with no throttle input. if the adjustments and steps below don't help out, you probably might be running on worn clutch plates or might require an oil change.

Apart from that, take the bike to the authorized service center and do the following:

On a cold or slightly warm engine (coolant temp bars less than 5)

1. connect the diag tool and check for any errors
2. fix if any errors accordingly (most likely there wont be any errors)
3. Even if there are no errors, click the option to clear dtc
4. then fire up the bike, but don't touch the throttle. Let the bike just idle for 11-15 minutes.. not less or more.
5. Shut off the bike, let it cool for a few minutes and then ride it and check.
if you try to ride the bike after clearing the dtc, it will jerk/shut off and would require you to give more throttle/slip clutch to get moving.. usually gets back to normal after a few km. So to avoid this and let the ecu relearn, follow step 4.

Re: KTM RC 390 Ownership Experience

Perfectly normal. The fuel pump pressurizes the system depending on the need. The pump doesn't prime all the time, and sometimes works during alternate ignition depending on the pressure requirement. Nothing to worry.

Appreciate the update, QZ. Since you're observing the stalling, I'd recommend you to check your clutch lever play. Secondly, closely observe the idling characteristics of the motorcycle. Stalling occurs when the idling RPM is erratic. Observe if the RPM is constant and stays steady during idle. A steady idle would mean steady movement of the vehicle without throttle input, as you've said. Check your clutch play, get it adjusted to your old settings once again and see if it helps. Keep your observations posted.

Cheers!
VJ

Re: KTM RC 390 Ownership Experience

Thanks but I removed the tyre hugger still I hear that noise. Its quiet loud thud.

By the way can anyone suggest NGK spark plug model. 2018 model uses Bosch VR 5 NEU.

Have also ordered a SPAL fan and will get it by end of month.

Also bought can of Engine Ice coolant. Will get it filled during first service.

Re: KTM RC 390 Ownership Experience

This is the ngk plug

Re: KTM RC 390 Ownership Experience

Thanks for the suggestion

Re: KTM RC 390 Ownership Experience

Hey,
I just wanted to know does the ngk iridium spark plug really helps with the low end of the bike?

I’m getting mixed reviews all over the net some say it helps a lot in low rpms while some say it’ll ruin your engine

And what’s the correct gap for it 9mm or 8mm?