[Inferno]

Hi all, I bought a '99 900SS earlier this week. It has 17k miles on it. The previous owner had it sitting in a storage unit for the last 6 years, so naturally there are some bugs that need worked out. I've replaced the spark plugs, battery, and timing belts, changed the oil, siphoned out the old gas (it was orange!) and replaced it with 93 and some fuel injector cleaner. I put almost 100 miles on the bike like that, and it was running real rough at first, but it started to clear up real quick.

I noticed that the line labelled drain on the bottom of the gas tank was capped, so after reading this post, I opened up the tank and found that the line that should have been running to it had broken off.

After replacing that line and getting everything back together, the bike seems to run a little better, but its still running rough below 4k RPM. I was trying to go 25mph in 2nd earlier and the bike felt real choppy and didn't feel like it wanted to stay running. My main problem is that taking off from a stop, the bike has no power and wants to stall unless I slip the clutch way more than I should need to. Any idea what could be wrong still?

 

[sofadriver]

try running a can of Seafoam thru it.
the stuff really works great on motors that have been sitting.

 

[bradblack]

on 600 that had sat in the crates for a while they often ran badly down low or at idle when pulled out of the crate for pd. i used to remove the mixture screws, spray carb cleaner up the hole and then give it a blast with the air line. tended to work well.

 

[Inferno]

Well I decided to ride the bike to town earlier to buy some Seafoam. It was running rough like usual, but after I made it about 5 miles from my house, the bike started decelerating when I was at constant throttle in 6th gear. I pulled the clutch in and the RPMs dropped to 0.

After pulling over, I couldn't get the bike to start again. The engine is cranking fine and it all sounds correct, plus I checked for spark after I trailered it home and spark is strong, so I'm thinking it has to be something in the fuel system. Ideas?

 

[sofadriver]

can you hear the fuel pump when you first turn the key on?

 

[hawkgt]

Can you hear the fuel pump when you first turn the key on?Did you replace the fuel filter while you were in the tank?Fuel Pressure?

Regards Bill

1999 Ducati 900SSie
1988 Honda NT650GT

 

[marlin917vs]

+1 fuel pump.
Mine had sat for 2 years and I just couldn't wait to run it.
Had the same thing happen to me.
The 'orange gas' managed its way through the filter just enough and smoked my fuel pump after a few rides too.

 

[Inferno]

I can hear the fuel pump when I turn the key on. Also, when the fuel level is very very low and the pump primes, I can see some gas spraying out to the side. I originally thought that this was coming from the return line, but could it be that one of the feed lines in the tank has a hole in it?

If this is the case, would that explain my issue here? This is my first fuel injected bike, so its a little different than troubleshooting with carbs haha.

 

[sofadriver]

yep - there's your problem!

 

[Inferno]

Sure enough, the line going between the filter and the pump was barely a line anymore. After I replace it (and the one going from the filter to the barb for good measure), the bike started right up and seems to idle better.

I haven't been able to test ride it because my rear wheel is out getting a new tire, but it should be back any minute. I'll report back with how it rides after I get a chance to take it out.

 

[sofadriver]

glad to hear it.
classic Ducati problem.
outside of the ECU circuits, you'll find most Duc problems are easy to diagnose and fix.
they're actually pretty simple machines.
invest in a manual from DesmoTimes. you'll be glad you did. (you will even find a pic of that exact problem. the guy knows Ducs! )

 

[hawkgt]

Glad to hear you got it going.I replaced all my in tank fuel lines with the plastic high pressure lines and Otiker Clamps.Bit of a Pita at filter change time with the lines being stiffer,but no concerns as with rubber lines being submerged in gas.

Regards Bill

1999 Ducati 900SSie
1988 Honda NT650GT

 

[marlin917vs]

Good for you. Fuel pumps ain't cheap!!
When I changed mine out, I used marine grade "immersion fuel line".
It's resistant to fuel on the OUTSIDE as well as the inside.
My P.O. has used regular old fuel lines too and after soaking in fuel for so long had really started to fall apart.

 

[Inferno]

I just used regular line as a sort of quick fix. I plan on pulling everything out of the tank over the winter and restoring it since its getting rather rusty in there.

Where'd you get the immersion fuel line?

 

[Inferno]

Alright, I got a chance to ride it today and it runs smoothly finally. However, I've got a new issue. If I pull the clutch in at 4k RPM or above, it'll just go to 5k and stay there. The only way to bring it back down is to slip the clutch out or shut it off.

I'm not sure what's causing it. My only thought would be a sticking injector, but if that were the case air would have to be sneaking in somewhere. Or I guess the throttle slide/butterfly (what do these even have?) could be sticking open as well, not really sure though.

So, any ideas before I tear the bike down to the throttle bodies to troubleshoot more?

 

[Inferno]

Just tried spraying starting fluid between the throttle bodies and the head with it running and the RPMs didn't jump up, so I don't appear to have a vacuum leak. Any other thoughts?

EDIT: Just took it for another ride and got some more info. I'm just going to start a new thread.

 

[marlin917vs]

I got my immersion line at Napa. It's used primarily for marine applications.
It does cost quite a bit more than regular fuel line, but for the peace of mind, IMO it's well worth it.
If your tanks starting to rust, check out the thread on POR-15. I did it to mine. It's truly AMAZING !!

 

[Inferno]

Thanks for the info. And I'll take a look at that thread come winter when I tear my bike down.

 

[hawkgt]

You may also want to consider using the plastic lines.These are used for the high pressure fuel applications in most modern cars.A little more difficult to work with then the flexible immersion type of line but more piece of mind in regards to failure.I am a Marine tech by the way and have used both.
Regards Bill

1999 900SSie
1988 Honda NT650GT

 

[Inferno]

I will look into those as well. Thanks.

Off topic: I just stumbled upon an NT650 and it seems like it'd be an interesting project bike. How do you like yours? PM me if you'd like.