2001 - 750 Runs rough then dies out - fuel delivery??

[benn80]

Hi All -

First post here, as I'm new to Ducatis - just bought a used 2001 750 a month ago with ~ 9K miles on it.  It had been recently serviced with all of the belts replaced.  It has been a complete blast to ride with no problems up until today.  I installed a battery tender hookup and went for a nice afternoon ride - I got about 5 miles down the road and lost all power at all RPMs - pulled over and it died out.  It felt like I ran out of gas, but there was fuel in the tank - lifted the tank to investigate thinking it was just a pinched hose, poked around a bit - then started it back up and it ran fine.  Another 5 miles down the road the same thing happened - throttle became unresponsive until it finally conked out and died.  Same thing, lifted the tank looked around a bit, then started it back up and it ran for another 5 miles..... I finally got it back home feeling a bit disenchanted with my new toy. 

I'd rather not take it to the shop if it's something easy that people have ran into before I'd love to hear it  - I checked all of the lines and I'm confident that none of them are getting pinched...   Just not sure about where to check after that - do the fuel pumps go out? is there an easy way to check ?

any troubleshooting help would be appreciated

[ducpainter]

There are a few things it could be.

If your bike still has the vacuum operated petcock I'd eliminate that. It's located just under the tank hinge.

I'd also try running it with the cap loose to see if the vent hose is blocked/kinked.

[benn80]

The original vacuum petcock is still hooked up - is there a bypass kit I should buy?

[ducpainter]

The original vacuum petcock is still hooked up - is there a bypass kit I should buy?

You can buy a Pingel style manual valve from a Lockhart-Phillips dealer for about $15.

5/16" in and out.

[mdriver]

If the bike ran fine prior to the battery tender install I would suspect that the problem is something simple like a loose or poor battery terminal connection. Keep in mind though even if the battery terminals are tight it doesn't guarantee they are making a good connection.

Welcome to the site and to Ducati ownership

[erkishhorde]

Clogged fuel filter? It's a cheap part, might as well replace it if you can't find anything glaringly wrong.

[Porsche Monkey]

Those diaphram fuel pumps are prone to wearing out over time.  If your bike is carburated then thats what it has.  When mine failed the bike would run great cold, and when you were moving at a good clip.  If you stopped or were caught in traffic for any length of time it would run out of gas very close to what your describing.  I'm attributing that to either the fuel in the tank heating up or the pump itself.  You can find rebuild kits for around 30 bucks from motorcyclecarbs.com I believe.  I ordered a kit from them but decided to eliminate the vacuum pump all together and installed a small electric pump and fuel regulator instead.  Oh and welcome to the forum.

[BastrdHK]

Sounds like a hose is getting pinched while tank is down and latched, but is not evident when you raise it to investigate.  Check fuel lines while tank is down....good luck   Let us know what you find!

[benn80]

Thanks all for the suggestions -
I'm busy dealing with finals today (ugh) - but tomorrow I plan on riding it around till it decides to die again.... my plan for trouble shooting assuming I can get it to die on me again is to A) open the gas tank to listen for any vacuum that may have developed, B) double check all fuel lines with tank down, C) - try to restart without lifting tank D) lift tank and move things around a bit then try to restart,  E) beat on it a bit and hope that it will run long enough to get me back home

I'm a little confused by whether the little valve thing right by the tank hinge is actually a vacuum operated petcock - or a vacuum operated pump.  If it is just a vacuum operated petcock i should be able to bypass it and put in a hand operated valve, on the other hand if it is a pump then I would somehow need to put another pump in.  It looks to me like it would simply be a vacuum operated flowthrough valve, and that gas should flow down to the carburetor without the need for a pump...... , any thoughts on this?

[BastrdHK]

It is just a vacuum operated petcock, not a pump.  I would replace with a petcock that has a manual on/off valve making future carb services much easier.  Don't forget to drop a couple slices of  in the tank for good measure

[jerryz]

Fuel filter can cause those symtoms if blocked.

[ducpainter]

Thanks all for the suggestions -
I'm busy dealing with finals today (ugh) - but tomorrow I plan on riding it around till it decides to die again.... my plan for trouble shooting assuming I can get it to die on me again is to A) open the gas tank to listen for any vacuum that may have developed, B) double check all fuel lines with tank down, C) - try to restart without lifting tank D) lift tank and move things around a bit then try to restart,  E) beat on it a bit and hope that it will run long enough to get me back home

I'm a little confused by whether the little valve thing right by the tank hinge is actually a vacuum operated petcock - or a vacuum operated pump.  If it is just a vacuum operated petcock i should be able to bypass it and put in a hand operated valve, on the other hand if it is a pump then I would somehow need to put another pump in.  It looks to me like it would simply be a vacuum operated flowthrough valve, and that gas should flow down to the carburetor without the need for a pump...... , any thoughts on this?

There is also a pump which is vacuum operated too.

It is mounted on the right hand side of the frame and is hexagonal shaped.

If my stock pump ever fails the bike will get a low pressure electric replacement.

[Porsche Monkey]

There is also a pump which is vacuum operated too.

It is mounted on the right hand side of the frame and is hexagonal shaped.

If my stock pump ever fails the bike will get a low pressure electric replacement.

Thats exactly what I did.  Works great.