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Discussion Starter #1
Dear members,

When de-accelerating my 750 SS 1992 to almost a full stop, the engine quits. All electronics keep working and it starts also right again. Just before this happens the red batterij sign on the dashboard goes on. However, all electronics work well and battery is in good condition.

If I keep revving the engine it does not happen.

What could this be?
 

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once the engine is hot what is your idle rpm? & does this happen when the engine is cold or hot--or both?-the generator light coming on to me would say to low an idle as it is not charging fully at low rpm. But I would check the battery -you say it's good but how old is it? and what voltage readings do you get during a load test? -If the battery is over 1 year old it could be suspect.
 

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The other question is --does the bike have the original stock flywheel??--or a lightened flywheel ? with the very light flywheels carb synch is very important. another thing to look at is all of the intake tract rubber's -do they need replacement ? --if they have any cracks in them they do
 

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Discussion Starter #4
Thanks for your response renn! The problem applies with a warm engine, normal rpm is 1000 then. I will check the battery this week to make sure. Will also check intake tract rubbers.

I think it has the original flywheel but can’t be sure about it. The engine did get a big maintenance job at the dealer including carb synchronisation.
 

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Load test that battery--and make sure it is still good & strong-another thing -just because the dealer did the maintenance service dont assume it was done correctly--I mean was the tech that did the job a old hand at this & been doing it for many years and knows what he is doing -or did you get that kid fresh out of school and this was his first--same dealer--but a big difference in what you get
 

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Load test that battery--and make sure it is still good & strong-another thing -just because the dealer did the maintenance service dont assume it was done correctly--I mean was the tech that did the job a old hand at this & been doing it for many years and knows what he is doing -or did you get that kid fresh out of school and this was his first--same dealer--but a big difference in what you get
 

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I had the exact same problem & symptom - would intermittently quit at traffic lights. Cleaned out carbs with attention to the low speed jet/metering needle/ passages and problem gone. Made low speed running smoother too. Do a site search and you can verify that the tiny low speed fuel feed is sensitive to any crud. Mine looked pretty clean when I had it apart.
 

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yes dirty or clogged pilot circuits could do it --the question I also have is did this bike sit un-ridden for any length of time?, or did this problem occur all of a sudden. Look inside the fuel tank-is it nice and clean or is it getting nasty inside, If you have crud in the tank that needs to be addressed first
 

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Yes
Just checked the battery and it’s good, 12.7V.
Yes but what does it go down to on the load tester under load?---just reading voltage with a voltmeter tells you nothing
 

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We have to “assume” the carbs were synched and timing Checked at the service. Dirty carb throats can cause this too. Just spraying carb cleaner into the carbs while running should clean that up. Many folks run SeaFoam with every tank to keep the tank and carbs clean. Bleed the clutch. If it’s dragging it can stall an engine at low revs.
 

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Could be a spark issue as well. Bad/weak coil or some other issue. I had the exact same problem and in my case it turned out to be a dying ignition (Kokusan) box
 

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If I keep revving the engine it does not happen.

What could this be?
Side stand switch?
I don't know how yours is wired or if you have the original suicidal self retracting side stand. If you have a wired switch, make sure the switch or the side stand itself isn't loose.
 

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Maybe , but they usually leak when hot if the fuel level is high, and the bike keeps running.
 

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1992 had a auto retract sidestand switch so nothing there. Sounds like carbs are not set up correctly .

The engine did get a big maintenance job at the dealer including carb synchronisation.
Was the dealer a well versed in carburetors?
many do not have mechanics that know what a carburetor is any more, did the problem start after the tune or before?
what does the dealer think as they released it after tuning as acceptable?
how long ago time and miles since tune?

A 750 may need a idle closer to 1100rpm and the gen light might be simply lighting as it stalls like a oil light does when stalling. Are you sure it is the battery light and not the oil light ?
 

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Discussion Starter #17
Thank you for your comments! I called the ducati dealer and they said that I could come back again and that they could increase the RPM (free of charge). I will try this next weekend and hopefully it works!
 

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and If it has a light flywheel in it and the RPM is not high enough it sure as hell will shut down, My 91 900SS needs the RPM set @ 1000-1100 to work properly and it has the stock flywheel in it
 

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Make sure that the engine is up to normal operating temperature when they set the idle or you hay get some idle hang. They should know this but be aware that if you get idle hang after they increase the idle that is not the issue and the idle will need to go back down. Bottom line they should be able to set the idle so it either idles properly or have a good reason why it does not.
 

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I’ve always been able to get rid of a hanging idle by richening the mixture a hair. Try another 1/4- 1/2 turn ccw on the mixture screws.
 
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