Fast tickover AGAIN - Euro4

Clive

Clive

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I know there have been many postings on the subject where the tick-over hovers around 2500rpm and solutions have been found in remapping, idle motor air leaks, exhaust leaks etc. but I am wondering whether my recent experience is an ECU issue.

The bike is a Euro 4 CR decatted with open factory pipes. The effect is not repeatable and has happened twice several weeks apart since open pipes and remap. Both times switching it off and on again cured it instantly. To me this eliminates any mechanical issue. As a computer systems engineer (in addition to other proper engineering disciplines), included embedded systems, it sounds like a volatile value used for the tick-over speed calculation being corrupted or maybe the idle valve went to sleep?

It fired up fine but shortly into the ride it was ticking over at a well controlled 2500rpm. If I put it into a high gear and let the revs drop below this as soon as I pulled the clutch in it would idle normally until I blipped the throttle when it returned to 2500rpm.

It is more a minor personality disorder than a full blown fault as the rest of the time it runs great, but based on these effects are there any inspired suggestions?
 
This may be the IAC setting in the ECU or the idle air valve.
May I suggest that you remove the fuel tank and disconnect the battery for 15 minutes or so.
This will force the ECU IAC programming into a re-adapt condition when you reconnect the battery and restart the bike.
It could eliminate the problem.

This same sequence significantly changed the IAC in my 961 when I changed out my dead battery in December.
My 961 NEVER started easily on the IAC. I always had to use throttle to keep the bike running or it would die.
After the battery removal, my bike now starts on the first stab at the started, with NO manual throttle at all.
It now initially revs to 2000 rpm on startup, then quickly downs to 1500, then slowly down to 1200 after about 10 seconds.
This was shocking to me since it had NEVER done this before in the 4 years that I owned it.

I tend to think that the problem is related to settings in the IAC that can be re-adapted.
Otherwise, why would my bike perform so differently now with no changes other than a battery replacement.
 
Thanks - I agree that this seems the only explanation how a the battery replacement could cure the idle issue so as a no-cost option it's worth a go.
 
Actually, until my accident, my bike started and acted like yours, BritTwit for 2 years. Flawless. Get the bike back after 6 months and I get that high idle all over again. Meanwhile, I'm blaming the dealership for remapping me to 77. They may have not remapped it at all. Could be I just got the opposite effect when the replaced the tank and possible disconnected the battery. You can't blip it down. It just goes up and hangs there longer. The response is horrible. But like Clive said, turn it off and restart. Not very convenient in most traffic. I'll find out when the weather clears and I bring it back to them
 
Depends on the ECU and what software is has, I have 2 Honda cars that if the battery is disconnected there is a risk of the idle not dropping to normal will in 2 minutes of a cold start if you do not re-train it on the first cold start but instead drive straight away. The trick to fix it is to disconnect the battery which wipes the ECU of the learned data and then do a cold start but do not touch the throttle until the idle speed drops to normal. No idea if it will work on a Norton and no doubt there are other ECU's that behave differently.
 
Ok boys and girls next part of the puzzle. Just got back from work. My 10 mile commute turned into a 45 mile ride - ye gods I love riding that bike!!!!! And just looking at it. And listening to it.

After a 10 minute rest it won't start so I turn it off, wait 15seconds and turn it on again. Starts first press without touching throttle. Tickover seems normal. Start riding and we're back to 2500rpm idle. Pull over and switch it off. Wait 15seconds and fire it up again. Normality returns.

This sequence of events is exactly what I got a few weeks back:

Why does the first power off/on put it into the high idle mode?
Why does the next power off/on fix it?
Why can't I be happy with one of those well behaved cheap scootery things with some sensible storage for my shopping??????
 
Clive said:
Why does the first power off/on put it into the high idle mode?
Why does the next power off/on fix it?
Click to expand...

We need to understand how the 961 re-trains/re-adapts after having been completely powered down.

Would be nice if Simon could chime in here and explain the process to us all so we are no longer guessing.
 
Perhaps the timing is out because the crank is out? Then when you turn off the key and everything resets, its luck where the sensors pick up?? It seems that after we rebuild an engine it starts a lot easier and idles a lot smoother. These have been engines with the crank way out if alignment. If you think about mechanicaly how the engine works half the ecu inputs are from one sufe of the engine and again then other side. If they’re not in line it wont run perfect all the time.
 
richard-7 said:
Yeah good luck. That would be admitting there is a problem publicly.
Click to expand...

Richard,

I don't believe so.
Every EFI design has to incorporate a re-adaption feature for when the ECU loses it's volatile data.
Such as power spike or when disconnected from it's power source.
Japanese manufacturers build in a re-adapt feature.
The EFI Triumphs have one as well.
There are lots of posts on the RAT forum from owners re-adapting after removing the airbox, installing new exhausts or replacing failed sensors.
This can require a period of riding about with the new equipment before the process produces a full re-adapt.

All we need to know is the procedure that is required to re-adapt the 961's ECU.
The do's and don'ts to successfully re-adapt/re-train the EFI system.
 
BritTwit said:
There are lots of posts on the RAT forum from owners re-adapting ...
Click to expand...
The Thruxton group of owners talk of cold start without touching throttle and letting it idle for 15 minutes.... no mention of battery power down and nothing official from Triumph as far as I know so maybe just old wives tale.
 
MxMartin said:
The Thruxton group of owners talk of cold start without touching throttle and letting it idle for 15 minutes.... no mention of battery power down and nothing official from Triumph as far as I know so maybe just old wives tale.
Click to expand...

Don't know about the new Thrux's (2015 on), but the gen1 air cooled (865cc) Bonnies with EFI have posted quite a few issues that required a re-adapt.
Sometimes required when battery voltage is too low.
 
To understand the idle issue we need to understand the algorithm which activates the idle control function. It could be more complex but my guess is it monitors for the engine speed dropping below a value, shall we say 2000rpm. It probably looks at the throttle position sensor to establish if the throttle is closed. This explains why false readings from the TPS, or air leaks stop it entering idle control mode. While riding try shutting the throttle, letting the revs drop to say 2000rpm and see if you can feel the idle control kicking in....

When it is stuck for some reason at 2500 rpm with the throttle closed it would never drop into idle control.

This could be because the ECU is not correctly fuelling OR it has left the air valve in a semi-open position AND/OR does not think the throttle is closed (ref the TPS calibration discussions). This operation is proven when it is idling high and I force the revs to drop below the trigger rpm in a high gear and pull in the clutch causing it to enter idle mode.

Either way there are many things which could give an elevated 'tickover' preventing it entering idle mode which is why we see the problem resolved by fixing air leaks, lambda sensors, TPS etc.

The high speed idle is not a fault in itself - just an indicator of problem elsewhere.



Or it could be Goblins in the air filter. My money is on the Goblins.
 
BritTwit said:
Richard,

I don't believe so.
Every EFI design has to incorporate a re-adaption feature for when the ECU loses it's volatile data.
Such as power spike or when disconnected from it's power source.
Japanese manufacturers build in a re-adapt feature.
The EFI Triumphs have one as well.
There are lots of posts on the RAT forum from owners re-adapting after removing the airbox, installing new exhausts or replacing failed sensors.
This can require a period of riding about with the new equipment before the process produces a full re-adapt.

All we need to know is the procedure that is required to re-adapt the 961's ECU.
The do's and don'ts to successfully re-adapt/re-train the EFI system.
Click to expand...

On the norton software its called “re-learn idle”. We were instructed to do this with every remap.
 
I worked at a car factory during the change from carbs to EFI, a very steep learning curve and a lot of mistakes were made. The biggest customer issue was idling, either too high, varying or no idle ie stalling.

The list of possible causes is long but it's down to 3 areas (or even worse a combination of the 3)

1. The ECU program is defective or corrupted.

2. The ECU live data is old and not updated for current conditions

3. A sensor or connected equipment is feeding the ECU the wrong data. (the ECU stored error codes may give a clue but don't take them literally as another faulty piece of equipment may make a fully functioning sensor give bad values)

When the engine revs are above a preset level and the throttle is closed the injectors are off, once the revs drop below the preset level then even with a fully closed throttle the injectors should kick in in readiness for the engine needing to idle. Sounds simple but its the cause of most EFI complaints.
 
I would like to know how much is controlled by the built-in ECU routines and how much is defined by the (Norton) programmer.
 
For sure the root cause of the wild idle phenomenon is the Idle Air Control, and the programming that enables it.
How the IAC is using the sensors (airbox temp, cylinder temp, tps, crank, etc) to control fueling is the culprit.
Without access to this area of the ECU, its impossible to affect a solution.

What seems peculiar to me is that this issue has been appearing on some 961's for a while already.
I would think that the factory would have noticed it to and made an all out effort to resolve it.
However, we now see some newer machines, MKII units with this same issue.
How could Norton allow such a problem to continue?

I have never owned an EFI machine that had such a problem.
I think most customers buy an EFI machine thinking that idling issues are problems that only old carbed bikes had.
There had better not be any wild idling V4 1200's or 650's in Norton's future, or happy customers will be hard to come by.
 
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