Ducati Monster Forum

Moto Board => Tech => Topic started by: He Man on November 13, 2011, 07:47:11 PM

Title: Engine keeps cutting off
Post by: He Man on November 13, 2011, 07:47:11 PM
The bike runs great, starts up just fine and ive poured miles on it with no bodies buisness, but the bike just randomly cuts out for no reason. I could ride the bike for hours no problem and if i come to a stop, it will want to stall and sometimes does indeed stall.

the engine has 29,500 miles on it as of today. its been through a few track days and has been a city rider all its life. pretty harsh life if i have to admit.

Im thinking the motor is just worn out will check the valves sometimes this week since the valve check is due at 24k.
Title: Re: Engine keeps cutting off
Post by: ducpainter on November 15, 2011, 03:43:33 AM
When was the last time the thing had any injection set up done?
Title: Re: Engine keeps cutting off
Post by: zooom on November 15, 2011, 04:03:02 AM
Quote from: ducpainter on November 15, 2011, 03:43:33 AM
When was the last time the thing had any injection set up done?

or the throttle bodies synched? ( thinking specifically since that would be a part of what DP is suggesting)
Title: Re: Engine keeps cutting off
Post by: He Man on November 15, 2011, 09:12:44 AM
i think 18k was the last time any non valve adjustment related work was done. (that was last year actually)
at 29.5k now. did valve adjustment at 19k with MBP collets (or somewhere around there). and i just checked them late last night, the closers were just slightly off spec. everything else is within spec.

fuel filter replaced last year with a Ducati OEM filter by dealer during tank replacement.

the TB was sync back with the 18k when i had my bike checked out. is it something i can do myself or does it require some tech devices to do it?
Title: Re: Engine keeps cutting off
Post by: ducpainter on November 15, 2011, 02:06:26 PM
I think you really need an ega to do it right.

Someone else knows for sure
Title: Re: Engine keeps cutting off
Post by: rule62 on November 15, 2011, 04:32:51 PM
I suggest resetting/checking the TPS. I had a similar problem at about 20,000 miles on my 620. Ran great, but would stumble and die at idle sometimes. Used Brad Black's <bikerboy.org> instructions and a volt-meter. It really cleared up the running issue.
Title: Re: Engine keeps cutting off
Post by: Cloner on November 16, 2011, 12:45:58 PM
All you need to sync the throttle bodies is a manometer (you can make your own) and a screwdriver.  You will need an exhaust gas analyzer to correctly set the air bleeds, though.

Sync and tps can both cause the symptom you've described.

For a twin-cylinder engine you can use a loop of clear tube for a manometer.  Use a tube five or six feet long.  Fill about two feet of it with fluid.  Hook each end of the tube to one of the nipples on the intake manifolds (one at each manifold, obviously) and hang the tube in a loop (high-low-high) so that the fluid is in a vertical position....the oil will fill the bottom foot of the loop, one foot at each leg.  The exact amount of fluid is irrelevant.  With the engine shut off the fluid in each leg will be at the same level.  When you start the bike the cylinder with the greater throttle opening will run slightly faster and will have a higher vacuum signal.  It will draw fluid into its leg and away from the other, showing an imbalance between the two legs.  Adjust the balancing screw to make the fluid levels even (after you've bottomed the bleed screws).

You can fill it with virtually any liquid.  I prefer a more viscous liquid, like transmission fluid or motor oil, as it tends to filter a bit more "noise" than a less viscous one, like water or antifreeze.