Loss of power at 5000-7000rpm

try completely disconnecting your PC3 and load the map with tuneECU.

Im not trying to have a laugh mate... seriously try it. If it doesnt fix the issue then just reconnect it back up (it is only disconnecting a couple of plugs).

Electrical things like the PC3's have been know to create gremlisn like this

So it happened again today on the way home from work.

Since the last time I've had a dying battery and replaced it just a few weeks ago. I'm thinking it must be the rectifier seeing as I've had the battery issue and the two times this has happened its been a real hot day ie 38DegC which makes me think it could be electrical in nature.

In any case I got home and took it for another ride after dumping my work gear and it was ok for a while after being turned off then on. Then on the way home it started to do it again at which point I pulled off the main road and turned off the bike while rolling then on again and it came good!

Will call the shop and find out how much a rectifier is and maybe try that, seeing as I've recently had battery issues as well.

Good luck sorting it and make sure you let us know what the problem was.

As for thrashing it, these bikes are made for it.

are you running a power commander?

Yep still running a power commander mate. Havent got around to trying it without. I know you are the TuneECU saleman but I have no cable and no clue about that. I dont see how it could be the power commander besides the grounding cable.

Only reason I say it is today I had no issues climbing right to the rev limiter. So go figure.

i know ducati pete was having a lot of issues with a defective PC3... ask him about it... he may be able to give some pointers

Will do mate. Just dont want to let go of my PC3 I guess. But I'm just about to head over to the TuneECU thread to study up!

I recently replaced my rectifier but definitely did not suffer any loss of power before. Nearly £70 for the part as well.

Moisture in the BGC. Pull it apart, dry it thoroughly with compressed air then pack it full (female side) of dilectric grease. Do a search on BGC.

John

Thanks for the advice guys. I got a quote for the regulator and its $175 AUD but seeing as I'm still under warranty till November I think I'll try some more troubleshooting before handing over my money.

I'll try pulling apart the BGCs and cleaning and spraying with dielectric grease to see if that helps it definetly wont hurt!

The other idea was to measure the voltage from the rectifier as I ride to see whether it is changing. As one of the guys had an intermittent failure of the rectifier in this way.

Otherwise the PC3 is coming out and we'll see how that goes and get a tuneECU cable.

Well it did it again this arvo on the way home. Yet another hot muggy day so that seems to be the only common thing at the moment.

I got some dielectric grease yesterday on the way home and this arvo I pulled apart the BGCs. Had a look in them and didnt see sqwat and then disconnected the PC3 completely after spraying the contacts with some WD40 and then drying before applying dielectric grease to both parts of the plug.

I took it for a ride and had no power issues besides the difference of not having a custom map. I'll see how it goes for the next week and if I can make it happen again I'll plug the PC3 back in (after cleaning etc of course) and then see what happens.

She does pop and bang like a mofo when rolling of heavy throttle now though. That akra map sure is rich on the top end!

Emu, if the bike is still under warranty, why not let the dealer have a go at it? were they not able to replicate the problem when testing?

the symptoms you describe - specially the fact that it runs like crap, you re-boot it and it's ok for a while, suggest a sensor... or something else that gets reset on the on/off cycle. bad ground somewhere, or maybe sticky 2nd-ary flies...(had that problem on a car, with simmilar symptoms). Do you have O2 sensors working? i really doubt it is PC, sure TuneECU is great -blah, blah, blah - not putting it down in any way, briliant piece of software and very usefull, but some here tend to try to find faults in PC just to justify swiching to TuneECU (just my opinion...). i've had 7 PC's (2, 3 and 3 usb) over last 10 years or so, never had one fail... never heard of one failing in our racing comminity, and almost everyone uses one... not saying it cannot happen, but i find it unlikely. Again, not putting down TuneECU, it's great, i use it, but i still have my PC, and i'm keeping it.

few suggestions:

sensors... all of them play a role in determining fuel injection and/or ignition rates, and are re-set on 'reboot':
MAP sensor
air temp sensor
ambient air pressure sensor
throttle valve sensor
2nd-ary throttle valve sensor
o2 sensors

other:
reg/rec - if you have a voltmeter, you can easily check it (procedure in the manual)
fuel pump/fuel pressure regulator - not sure how to check it, other than trying a new one...
fuel filter/line obstructed
2ndary flies stepper motor
air filter (unlikely unless O2 sensors enabled)
air leak around TB's
vacuum hoses (if you did not remove them)
SAS leak/failure (if still there...)


intermittent problems are a real pain, hope you get it - or at least can replicate it for the dealer, since you're still under warranty...
cheers!

I think you'll see that the problem is fixed (if you lubed the connector properly...which it sounds like you did).

Moisture can enter throught the back of the connector where the wires pass through the rubber grommmets (appears to be more likely through the PCIII connectors as they pass more than one wire through each grommet). The slightest (and I mean slightest) amount of moisture can short the pins in the connector (not causing any physical damage) which can easily confuse the ECU causing all sorts of running issues.

The dealers don't have a clue. I've tried explaining it to a couple but they just don't get it. This connector routes all of your connections to the ECU (every sensor on the bike) so if one or more contacts are shorting intermittently the ECU tries to compensate for what it perceives as an issue causing all different sorts of running issues.

I hope this helps you. I've tried to explain this to this forum until I'm blue in the face. A few have become believers from their success but I cannot seem to convince the majority so I've all but given up.

Once you've convinced yourself the issue is resolved you can hook your PCIII back up but because of the additional wires entering the connectors you have to pack the shit out of the female side with dilectric grease.

Keep us advised.

John

Thanks Smoky and lowrance.

I got a lift to work today so no further update.

The shop are quite keen to help me out which is refreshing but when I took the bike to them last time they couldn't duplicate my problem and neither could I. If I can work out what it is they're more than happy to help but otherwise atm it could be anything.

I'll give it a week or so without the PC3 and see what happens and move from there. I had the exact same idea as you John so will let you know how I go.

Well looks like you guys were onto something. I had the same problem this arvo. Hot humid day 36.5 DegC god knows how humid but very!

So I've got the PC3 disconnected at the moment and cleaned and dielectric lubed it. so it wasnt the PC3 at least. So I might just plug that back in now seeing as it runs better that way!

So looks like I'll have to do a bit more troubleshooting. I guess the one thing I've worked out is it's not always in the same spot in terms of RPM but the common factor is it's always above 35 DegC and humid (well thats what I've noticed so far at least).

Will keep looking and I think now that I have eliminated the PC3 it might be time for the warranty to take over for sure.

Bummer you're still having this issue.

I'd pull the BGC apart again (it's free) and really pack dilectric grease into the female contacts. You can't really use too much of the stuff (it's the same stuff KTM use to pack the BBC connecting generator to rectifier). A spray grease will have a hell of a time getting down into the contacts. The stuff I use comes in a tiny tube (similar to toothpaste) which allows you to force the grease down into the connector.

Give it a try, you've got nothing to lose.

Good luck!

John

I hear ya lowrance. I'll give it another packing of grease (looks like toothpaste tube as well).

Its at the shop at the moment and the guys are having a look. So far they havent had any luck with reproducing my fault but they'll try harder tomorrow!

I'll see if I can give them a hand as it only seems to have a problem after it's warmed up.

Best of luck!

Well they've had the bike since Tuesday night and havent been able to replicate the issue.

I've taken it back as it's my main form of transport and they cant fix what aint broke.

I'll reattach the PC3 and pack the connectors with dielectric grease and then check all the other plugs that I have access to while I am there.

Will let you know. But looks like this will be a long one. I hope I can get it fixed before the warranty is up!

So it was fine for a good hard ride on saturday but today it was crap on the way home again. Turning on and off the ignition makes it go away for a while. You sure can tell when its running wrong.

I hooked up a multimeter and took it for a ride and it never went over 13.98V surely it should have been higher? ie 14 - 15V

Looks like I'll try and take it back to the shop again and see if they can pull it up in the diagnostics machine.

Emu,

I know you're probably tired of hearing this but I still believe moisture in the BGC could be your problem. When moisture enters that connector it can get in behind the face of the connector (back where the wires are crimped to the contacts that then get pushed into the connector body itself). The moisture in this area can still short out the contacts. I'm not saying that this is definitely the case but it was on my buddie's SD. After a thourogh blowing out with compressed air and a liberal amount of dilectric grease his problem was cured.

Just sayin....

Again, good luck and I hope you get it sorted soon as I know how frustrating this kind of intermittent running issue can be. I chased my symptoms for 6 months before I discovered the moisture in my SD's BGC and sorted the problem.

John

Hi Lowrance,

Firstly thanks for your dedication to the dielectric BGC connection issues.

I cleaned out with WD40 and packed the BGCs good and proper with dieletric grease packed twice for good measure. ie packed then plugged together then packed again. I'm using the toothpaste tube and the edge of a screwdriver to pack my plugs. I will be doing the rest of the plugs this weekend time permitting.

I took the bike back to the shop yesterday and they hooked it up to the diagnostic and it was reading fine (wasnt running poor at the time) the thing they did pick up which I hope is a related issue is the voltage was quite low. ie 13V (from the diagnostics screen)

When we hooked up the voltmeter to the battery it was reading 12.7V and dropping when switched on. when started it was reading about 13.5V and at 4000-5000rpm wouldn't go above 13.6-13.8V. Changed out the rectifier for a good one that was know to work and got the same reading. So atm we are looking into that the alternator is possible underperforming. The mechanic reckoned it should read about 14.2V when at 4000rpm and higher when idling as there is no load.

What sort of figures do you guys get from your bikes with a working system? Reason I ask is in the manual and Loony888s post the ignition system is affected by low voltage which may lead to poor performance ie like what I have.

So what voltages do you guys get from your battery when idling and when at 4000-5000 rpm as per workshop manual?

Haven't checked mine recently but was also told that low voltage during charging can result in running issues. Not experienced this myself...yet.

There is another connector that KTM pack with dilectric grease. It's the BBC (big brown connector) that connects the alternator to the rectifier (under chin fairing). Wouldn't hurt to pull this connector apart, clean and re-lube it. If the grease has migrated out resistance will build up, generate heat and cause a slight voltage drop.

John

if my memory is correct, i think i had 13.6 or 13.7 at 4K, no load... i thought it was pretty low, but never had any problems... also, i think the system only detect when voltage falls < 10V

the thing is though, a weak charging system/battery would not explain why when you shut her down and reboot she's ok... the longer you'd ride, the worse it would get, and re-starts would make it worse, as they drain quite a bit of juice from the battery...
hot & humid conditions that seem to trigger it would suggest condensation... check all the plugs you can get to that connect any of the important sensors (i found water in o2 elliminator before...) also, vacuum lines might get water condensation in them.

check for a vacuum leak on manifold/MAP sensor... most sensor failures result in error codes, but MAP might be fine but getting wrong reading due to vacuum leaks (running rich & retarded), or conversely air filter/vacuum line blockage(lean and advanced)

is the loss of power in any way related/dependant on throttle opening? ie WOT vs say 5%? how about >7K, and <5K?

also, check manual 7.20-7.37, it has some explanations of various sansors and their testing... not sure what else to suggest buddy, in cases like that i tend to blame sensors, but i think i'm biased... (used to own a Ford )

So a short update.

I havent had a repeat of the issue since the last time and still riding every day. The one thing I have done although I dont think could be entirely related was the scottoiler I have fitted I had accidently turned right up (each time I thought I was turning it down! doh). So I adjusted it back to were it should have been and haven't had an issue since only time will tell I guess.

I did however have the 15k service just done and everything was fine except the throttle bodies were way out, and the spark plugs were white as well as the gasket was very dry. They thought I should reconnect the PC3 as they said it was running lean due to the white plugs as I had told them I had disconnected it (they forgot I also told them I had reconnected it) when initially troubleshooting. During the last visit they also reflashed with the Akrapovic map just incase.

So do you think me riding it when it had these issues it may have done this due to running too lean? Or is my custom map too lean?

I think that as the throttle bodies were way out the mix would have been quite bad and may have lead to this. But it's hard to tell.

Man does it ride like a missile now! Good to have her back to old form.

I think I will need to get the throttle bodies readjusted more often given all the stop start it gets which is probably causing additional loosening of the throttlebody sync.

Hi emu,

Since the problem persist some other possible issues.

Fall over sensor in the headlight. When the bike falls over this stops the engine. Some failed and from memory you can bypass it or some people glued the ball in place. Don't keep riding it bypassed for too long as a fall might catch your limb in the wheel and the sensor won't switch the engine off.

Alarm or alarm plug under the seat. If the "dummy" plug is not plugged in properly or you have a faulty alarm this could stall the engine. (or moisture in the plug)

Side stand switch, I know.... but it is possible.

Hope this helps!

Guy

Is this the Scott oiler that hooks up to your vacuum lines?

Disconnect the PCIII completely and just let the connectors hang there. Thoroughly dry (with compressed air) and lube the stock BCG with "dilectric grease". You've now eliminated the weakest link-the PCIII.

Do it and reoprt back with results! Don't make me get on a plane!

John

lol thanks lowrance. I did actually try that already and it did nothing.

I had the same problem. No FI and nothing wrong when tested with the diagnostic tool.

It was a loose front cylinder spark plug connector.

The problem comes at 6 to 7000rpm because at these rpms the lc8 have the biggest vibration and the plug looses contact for a second.
The bike continues to run with one cylinder until you fully close the throtle and open it again.

Check your spark plugs and good luck!!

Thanks TaliG.

I think I've fixed it now by going thru all the plugs around the cylinder heads and throttle bodies. Pulled apart WD40'd let dry and then packed with dielectric grease. All seems fine now but as it is typically only at high RPM it makes it hard when the highest speed limit is 70 km/hr.

Guess I'll be doing a lot of riding around in 1st gear to confirm it's gone.

It may have been just like you suggested that the spark plug connector had come loose as I pulled all these while I was greasing and refitted. Will see if it comes back and try that to fix it if needed hopefully not.

I'll be taking it for a long ride this weekend to see if I can reproduce it and unleash the beast!

Good to hear you've (may have) got it sorted mate! Not the plug wire as that would have been consistent (not intermittent). I think you've chased the water outta the plug. Now make sure it stays greased properly and you should remain problem free.

I'm really thinking about jumping on the Tune ECU bandwagon to eliminate the PCIII (and the shitty Chinese knock-off plugs DJ uses). This should rectify problem indefinitely. If you look at the back of the DJ plug there are 2 and sometimes 3 wires running into the back of the connector through a rubber grommet that was designed to seal around 1 wire only. POS design!

John

Well latest update is that it may have just been something simple like ignition coils not being fully seated.

Today on the way to work after swapping out one of the ignition coils (it rattled when you shook it) I think it may have also been a possible cause of my issues.

My mechanic told me to make sure I'd seated them in completely by pushing them (by hand) as apparently sometimes they come out. I think the higher rate of ignition was making it have more issues than at lower speeds etc. When it seats you can feel it "clicking" as you push it in. Turns out that this is an issue on the RC8s as well, as there is no leak path the trapped air when heated up pushes up the coil.

So just another thing to check if its running rough etc.

I'll report back if its a permanent fix for my issue but so far its all good and I sure do love this bike!

Maybe it's something painfully simple like the spark plugs or fuel pump?


Edit: sorry didn't see this thread had a second page. Hope seating your coils properly solved the problem.