About the problem of high idling. (2014 cb1100ex)

[max]

Thanks Dave, i just remember that someone had a delayed repair but you're right, sometimes it does not work.
Also had another look at the spreadsheet for more background.

( Click on the picture for a better quality shot )

Have been using my scope to capture some iacv operations, here is what happens on startup;


Notice that the green trace leads to open the iacv, then returns some steps to arrive at the startup position.

Here is the turnaround point a bit clearer;


and here is what happens if you blip the throttle;


Notice the in-complete puses, the ecu just cuts them off regardless, i wonder what software changes they have made to the 2014 model's software to make this problem appear sometimes.....

[SportsterDoc]

Nacho, did you (a) disconnect ECU (key off) to "wipe" the contacts, also check condition of wires at connector and (b) that all contacts are fully seated in the ECU connector?

Be good to explore as many options as practical while this forum remains alive.

[Lord Popgun]

You know Max, I’m going to have to take a look at the scope video I made when we first started looking into this and compare it to yours. Edit: I don’t think I did the IACV. I know I did the speed sensor and front turn signal.


I wish Nacho was close by so I could hook up the diagnostic tool and o-scope and try to see what is going on better.

[PowerDubs_imp]

As someone that makes their living in an unrelated field that used to be mechanically driven and is now forced by modern standards to be electronic BS - much of this garbage is political grandstanding more so than actual benefit

Yes, having the idle be able to adjust itself for minutia may in theory show a reduction/ gain on paper but the associated cost of equipment, problems, and cost for said equipment both for production and replacement parts are not worth it in the end

– so we all know that motorcycles existed for many decades on a simple set screw for idle and even the early throttlebody fuel injected units so- is there not a way to backdate mechanically (there probably is since I have seen Honda throttlebody‘s that look very very very very similar with a mechanical throttle set screw) so let’s stop messing around and figure out how to “retrospec this“.

[max]

Cheers Popgun, i was just curious what i could do with my new automotive tool.
Once i got the voltage scale dialed in it was very easy to get the pulses displayed, it does a "deep record" function, i press "rec" , the scope starts rolling and records all the wave forms for a useful amount of time until i press "stop" and then i can two-finger zoom in to the place i want to have a look at and take a screenshot.
Here is the thing in question, the project is called " hs402 " it is a cheap samsung android tablet with an stm 32 micro board.
It uses two a/d converters for the two channels and a lot of on-board memory to collect and store the waveform data;



This will give you an idea how it works;
https://www.youtube.com/watch?v=TdVszkCzRYE

For what i wanted to do i just added four more inputs to the design with a potmeter each

Would be an eye opener to find out what the difference is between waveforms in an affected bike.

Question for Nachodaddy; when the bike plays up and you switch it off and back on again and initialize the iacv ; is the engine speed 1000 rpm?
And thanks for the explanation, it gives me more clues to work with, cheers.

[GoldOxide_imp]

Thanks Dave, i just remember that someone had a delayed repair but you're right, sometimes it does not work.
Also had another look at the spreadsheet for more background.

( Click on the picture for a better quality shot )

Have been using my scope to capture some iacv operations, here is what happens on startup;


Notice that the green trace leads to open the iacv, then returns some steps to arrive at the startup position.

Here is the turnaround point a bit clearer;


and here is what happens if you blip the throttle;


Notice the in-complete puses, the ecu just cuts them off regardless, i wonder what software changes they have made to the 2014 model's software to make this problem appear sometimes.....

Nice capture max, literally.

Question: Can you clarify what the Green Channel signal represents and what the Yellow Channel represents?

[max]

Sure, that's easy.
Imagine that the green one is your left leg and the yellow one is your right leg.
You step your green left leg forward first followed by your yellow right leg, take 50 or so steps forward and then you reverse the sequence by walking backwards.
That is what the iacv does, it has two sets of coils, coil a steps first followed by coil b, this moves the rotor in one direction, if you reverse the sequence; coil b first then coil a it reverses direction.
That's why it is called a " stepper motor "


The reason the iacv is taking so many steps is to make sure it is at the open end stop and then " stalls " or slips at the very end, then it takes as many steps in the closed direction as is determined by the engine temperature to arrive at 1000 rpm.

Both voltages are the same value but i reduced the size on the screen of the green one to make it look clearer to see the reversal in the sequence.

[peterbaron]

You know Max, I’m going to have to take a look at the scope video I made when we first started looking into this and compare it to yours. Edit: I don’t think I did the IACV. I know I did the speed sensor and front turn signal.


I wish Nacho was close by so I could hook up the diagnostic tool and o-scope and try to see what is going on better.

Oh ya!.....so now we have to use a scope for a turn signal to see if it works ??

[Nachodaddy]

Nacho, did you (a) disconnect ECU (key off) to "wipe" the contacts, also check condition of wires at connector and (b) that all contacts are fully seated in the ECU connector?

Be good to explore as many options as practical while this forum remains alive.

SportsterDoc,
I have not disconnected the ECU, but I have had the battery leads disconnected a couple of times changing out my battery maintainer leads. Haven't paid attention to changes in idle after that.
Is it possible to get to the ECU without removing the fuel tank? In the manual, the ECU is referred to as the ECM, right?
All the wires and connections look new and in excellent condition. I don't think this bike has ever been in the weather, except hot, dry weather.
Thanks for your help.
Prolly should get some RLETs just in case.

[GoldOxide_imp]

Sure, that's easy.
Imagine that the green one is your left leg and the yellow one is your right leg.
You step your green left leg forward first followed by your yellow right leg, take 50 or so steps forward and then you reverse the sequence by walking backwards.
That is what the iacv does, it has two sets of coils, coil a steps first followed by coil b, this moves the rotor in one direction, if you reverse the sequence; coil b first then coil a it reverses direction.
That's why it is called a " stepper motor "


The reason the iacv is taking so many steps is to make sure it is at the open end stop and then " stalls " or slips at the very end, then it takes as many steps in the closed direction as is determined by the engine temperature to arrive at 1000 rpm.

Both voltages are the same value but i reduced the size on the screen of the green one to make it look clearer to see the reversal in the sequence.

That's great max - thx.

Can you quote the module signal labels or pin IDs (or an image showing "where") you hung your probes off for membership folks who wish to repeat your results for themselves?

Maybe you have elsewhere in the Forum - so maybe just re-paste the URL here. This is useful info for those who may encounter similar run-time behaviour challenges and may wish to compare.