1200 GSA rough idle/stall problem

[motorbaker]

Hi. I'm hoping there might be someone here who can help.

2007 GSA. It's developed a rough idle. If I add a Power Controller, after 5 or 10 minutes of riding, once the engine is up to temperature, this happens:

YouTube - ‪07 GSA rough idle issue‬‏

It's been checked with a GS911 - nothing - and the coils have been checked and are fine. And it's recently had its 36k service and all was ok apart from the rough idle/stal.

So I'm drawing a blank and getting frustrated as I'm off on a 6,000 mile trip in a couple of weeks. Can anyone help diagnose the problem?

[Toyark]

First of all RE: "it's recently had its 36k service and all was ok apart from the rough idle/stal."
Surely you should have told your dealer then if you've paid for a service and this happens?

In no particular order, I'd check - to try and isolate the problem
1- your power commander -
has it been installed correctly?
is it tuneable?
is there corrosion/water in the connectors? (classic fault)
Importantly- does the bike run correctly without it?

Check point 5 below first!

2- Bridged Spark plug?
3- When was last time you have the valve clearances done?
4- Air filter - last checked/changed?
5- Throttle cable seating - easily disturbed when the tank is removed-the cables are attached to the throttle bodies
6- alternator output?

[motorbaker]

Thanks for your response, Bertrand. The service was done privately (by Steptoe on the ukgser forum) who knows his stuff and the idle issue has him stumped.

1. Without the PC it doesn't stall but the idle is rough. Here it is on video, without the PC:

YouTube - ‪07 GSA rough idle‬‏

The PC was installed correctly, has a custom map and I've greased the connectors. I thought it was a PC problem at first and Dynojet sent me a replacement, but the same thing happens. For some reason, though, it's worse with the PC as you can see from the first video.

2/3/4 - all taken care of at the last service (2 weeks ago.)

5. Looks OK.

6. Don't know.

Looking around other forums, things that might be factors are
Stepper motors
Crank sensor
Vacuum leak

Do any of those sound likely in this case? The intriguing thing is that the PC makes it worse but is not the source of the problem!

[T.REX63]

Originally Posted by motorbaker

...
Looking around other forums, things that might be factors are
Stepper motors
Crank sensor
Vacuum leak

Do any of those sound likely in this case? ...

When you had the GS911 connected, did you cycle the stepper motors? Any difference?

[motorbaker]

Originally Posted by T.REX63

When you had the GS911 connected, did you cycle the stepper motors? Any difference?

Yes, they were reset, but then gradually moved up one side followed by the other when the engine was restarted. The guy who did the service said he'd not come across this before. All he could think of was the coils, which he checked and they are fine apparently. That's as far as I've got.

[T.REX63]

Originally Posted by motorbaker

...All he could think of was the coils, which he checked and they are fine apparently. That's as far as I've got.

Without knowing how the coils were checked, I would swap the main (straight) coils between cylinders and see if anything behaves differently, since that is easy to do...