[magus]

I realize there have been a number of threads relating to rough running and bikes quitting when idling (or not idling at all) but I find my situation a little different from what I have read here and thought I might get some help on the analysis of my particular problem.

'06 SC (engine number post valve guide issue)
Speedcell LifePo battery (just under 2 years old)
Mosfet r/r (under tail mount)
about 7500 mi with fairly recent full 6k service

Symptoms:

starts fine cold; generally smooth idle
bike runs well
when bike is warm (hot) it will typically die when shutting down the throttle; bike starts up fine but throttle input required to maintain idle

 

[YellowDuck]

An easy diagnostic sort of thing to do (might even turn out to be a fix) is to open the airbleed screws a bit and see if that helps. It may simply be too rich at idle when it is hot. If it doesn't help it is easy to put them back where you found them - just count the turns (they may actually both be totally closed currently - that is common). I'd suggest turning them both out the same amount, 1/4 or even 1/8 turn at a time until you get the idle speed you like.

I had exactly the same issue you describe - at a track day the bike suddenly stopped idling properly when hot, and would stall on closed throttle. I didn't have the laptop and VDST with me to adjust the trim, so I just did the airbleed thing and it was a 100% fix. That was over a year ago and it has been running perfectly so I haven't even gone back to investigate it in more detail.

If it works you will then need to let it cool and make sure it hasn't raised your cold idle speed too much.

 

[greggers]

I would suggest doing some electrical diagnostics before fiddling with the bleed screws. Are you running stock exhaust/ecu?

 

[YellowDuck]

I knew someone was going to say that....

The way I see it, there is no electrical diagnosis that is simpler or quicker than turning out the air bleeds. You need a screwdriver and 60 s of your time. If that doesn't fix it, then put them back as they were and proceed to check the R/R, TPS, etc....

 

[greggers]

Ha no worries, I just feel like the airbleeds are one of those things that are easy to screw up (no pun intended), better to do some checks first before you fiddle with anything at all.

 

[konstantin690]

^ Agreed and ^^ Agreed ......
Although airbleeds is the first thing come to mind you cannot just "back-off" them based on just "correct" idle speed.
Even 1/4 turn can affect CO emissions enough to get you out of the 4% to 6% CO optimum range. A CO exhaust analyzer is needed to correct adjust the airbleeds.

 

[magus]

I would suggest doing some electrical diagnostics before fiddling with the bleed screws. Are you running stock exhaust/ecu?

I have a full Termi system with DP ECU.

 

[magus]

I had exactly the same issue you describe - at a track day the bike suddenly stopped idling properly when hot, and would stall on closed throttle. I didn't have the laptop and VDST with me to adjust the trim, so I just did the airbleed thing and it was a 100% fix. That was over a year ago and it has been running perfectly so I haven't even gone back to investigate it in more detail.

Interesting. The first I noticed this issue was at a track day as well. About half way through the day when I would come off of the track, the bike would just quit at idle.

Thanks for the input. I'm tempted to try the airbleed screw approach as I don't have any of the diagnostic tools.

 

[greggers]

So my thoughts from my albeit limited experience and reading are that, on FI, computer controlled bikes like these, when the motor just cuts out, it's often something electrical. There are numerous sensors, wires, and connections being made throughout the bike, and the ECU is set up so that if any of them read out of spec, or can't be read, it shuts off the fuel. Now if the check engine light isn't coming on, you can probably rule out a sensor.

When you installed the exhaust/ecu, did you have the TPS reset?
Have you checked the air filter, how clean it is?
What do your plugs look like?

 

[magus]

The termi and ecu were on the bike when I bought it so don't know what was done. I haven't checked the filter or plugs yet but will. Thanks for the input.


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[tristan tumble]

Have you figured out the issue? I'm having the same problem and was hoping there was a solution at the end on this thread.

Thanks
TT


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[UKDUCsRUS]

I would first check the balance of the throttle bodies, then reset the TP.

Here's a article that may help...
http://www.webbikeworld.com/ducati-motorcycles/gt-1000/ecu-throttle-body/ecu-throttle-bodies.htm


Let us know if it does.


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[UKDUCsRUS]

http://www.bikeboy.org/ducati2vthrottleb.html

And if your real hands on......


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[bLxZe]

I have a similar issue as well. Latest instance
(which has happened in the past) was yesterday while I was in stop and go traffic. If I let off the throttle the idle would sputter and I would have to give it some throttle to keep it running. At one point I didn't do it quickly enough and the bike stalled in traffic. I was about 10 or so minutes into my ride at a normal operating temp. I think my VR is the original stock and last I checked it didn't show signs of overheating though I can def feel heat under the seat.

 

[bevelsport]

My issue is similar. An 2006 SC with full Termi. Starts and idles perfectly when cold. Won't idle immediately after a warm or hot restart. After running for a few minutes, it will revert to normal idle. There are no symptoms while riding at anything other than "off throttle."

I suspect that a sensor is the issue. In looking over the Shop Manual for the 06 SC, I would suspect the Air Temperature/Pressure sensor or a Stepper Motor malfunction.

The manual calls for using the DDS (Ducati Diagnosis System) to check the sensor. My guess is that there is a resistance value for the sensor to indicate failure. Not knowing that value hampers any precise troubleshooting.

The Stepper Motor reacts to, among other things, information from the sensor. It is only active at throttle angles up to 30 deg. That is exactly the area where I am experiencing my problem (and perhaps everyone elses.)

Does anyone out there have a value for the sensor????

Personally, after reading how the system works, I am reluctant to fiddle with anything without having proper values for the sensor or a DDS.

 

[greggers]

Someone needs to come up with a kit to remove the stepper motor, it causes more trouble than it's worth.