96 M900 won't stay running please help!

[hcarsch]

Hi all new to Ducati and this forum unfortunately having a bad first experience!

I purchased a 1996 M900 about two weeks ago. Completely stock mechanically with 12k miles, dealer serviced. The PO just had electrical system checked out (bad fuse) and the fork seals replaced. He picked the bike up from the dealer, rode ~45mins to work, then to my office to show it to me, and then ~45mins home. Two days later he rode ~45mins to work, to my office, then followed me to my house where we did the deal. He parked the bike in my garage - I went to start it the next day and have not been able to ride farther than the end of my block since.

I was able to start the bike with 1/2 choke, it ran great in the garage at idle, when idle rose after a few mins i cut the choke back, the bike kept running but then when I went to pull off it sputtered and died. I could not get it to start back up and I killed the battery in the process. I went out and bought a charger the next day and experienced the same thing. Bike started right up, ran well, and then halfway down the block sputtered and died. After pushing back to my garage and putting back on the charger it fired right up and ran fine again!

Both myself and the PO thought the battery was the culprit since the dealer had noted it was weak. The next night I replaced it with a brand new battery proper charging time, etc. but no luck - same exact experience I could not make it out of my neighborhood without the bike bogging down and dying.

The next day I filled the gas tank and this resulted in the best running of all - normal idle for what seemed to be a very long time. I through all my gear on thinking perhaps the tank had just been too low - once again did not make it more than 2 blocks!

Does anyone have any suggestions? Originally I thought the petcock had been shut off and I just forgot to turn it on - but this bike seems to have the vacuum petcock? The coincidental thing is that each time the bike has run it has had the tank flipped up first - almost as if fuel is getting forced into the lines but as soon as I sign on and try to ride the fuel that has been forced in burns up and the bike dies. The major thing that does not add up is that I personally witnessed the PO riding the bike problem free on multiple occassions including right into my garage!

I really hope someone can help - I've always wanted a Ducati but this experience is making me wish I'd bought another Japanese bike. It feels like I'm missing something simple but I'm stumped here. Thanks.

[hooligan machinist]

 If you've had the tank up, check for kinked or pinched fuel and vent lines.
Run it until it dies and then open the fuel cap. If you hear a whoosh of air check the tank vent tube.
It's the most common culprit. Even if it's not pinched it could have an insect nest in it or some other kind of blockage. Even if that isn't the problem, it's a good place to start.

[needtorque]

Could be a fuel filter.  Patially clogged  and with a full tank enough force from gravity to push through it but when lower on fuel there would be less pressure and give the out of fuel symptoms.

[ducpainter]

...

try eliminating the vacuum petcock if the fuel lines aren't kinked.

[darkduc7]

this is a shot in the dark, but i once had a problem with a kinked wire on my m900. it would run fine, and then when i would go to ride, it would die unexplicably. try idling the bike and moving the handlebars from lock to lock, and shake the bike side to side. you could have a frayed or kinked wire cutting the bike off or even a throttle or fuel line doing the same. in my case, it was the kill switch wire that was kinked, and when i went to full left lock, the circuit would open and shut off the bike.

[ducpainter]

this is a shot in the dark, but i once had a problem with a kinked wire on my m900. it would run fine, and then when i would go to ride, it would die unexplicably. try idling the bike and moving the handlebars from lock to lock, and shake the bike side to side. you could have a frayed or kinked wire cutting the bike off or even a throttle or fuel line doing the same. in my case, it was the kill switch wire that was kinked, and when i went to full left lock, the circuit would open and shut off the bike.

The kill switch wire on mine frayed against the frame and would blow fuses.

Very strong possibility.

[ScottRNelson]

From the way you've described it, the first thing to check would be a pinched fuel line.

I never had a problem with my 1997 M900 until having some service done and the fuel hose was moved a little bit.  Then the next time I raised the tank and put it back down the fuel line was pinched.  It started and ran just long enough to go about one block then died.  But since I had read about that issue on the Monster e-mail list (two generations back from this forum), I knew how to fix it.  I probably had that issue two or three times overall.

I would suggest having a good look at the fuel line routing from the tank to see if rotating it a little bit or possibly shortening it (or lengthening it) will prevent the problem next time the fuel tank is raise.