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Discussion Starter #1
Great.....Just got my 2002 ST4S a couple of weeks ago. I'm not a big mechanic so I'll see if I'm cut out for this Ducati thing. Two days ago on my way home it stumbled a bit like it was running out of gas...I downshifted and it cleared. Went out today and it will turn over but won't start. I'm not sure if this is normal but when I crank it it will turn over and if I give it about a quarter of gas it will turn over faster.

What is the first thing to check....and remember that I'm a newb so please be as self explanatory as possible....That is if you tell me the flux capacitor next to the thermo wiget is corroded I may be asking dumb questions like "where is that"? Any help is appreciated.
 

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There have been a lot of "my bike won't start" threads posted here since riding season began. For starters (no pun intended), skim through the thread titles dating back to about May 1st and you will find several threads which may help you.
 

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Discussion Starter #3
Yeah thanks...I checked them all but none seemed to display the same issues.
 

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my well worn "bike won't start" tale

Out of the box, the 02-ST4s cannot be started with the sidestand down, even if the bike is in neutral. My 02-ST4s was equipped with an aftermarket device installed by the previous owner which by-passed this feature. I developed starting problems which were attributed to this aftermarket device. Once the device was removed, no more starting problems. Of course after that I could only start the bike on the centerstand if I wanted it to warm up, but that did not bother me as I always parked it on the centerstand.
 

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Could be a variety of things but here are a few to check:
1. Fuel Filter clogged.
2. Fuel line split in tank.
3. Fuel pump relay.
4. Fuel pump itself.

The fuel pump should turn on when you turn on the ignition. You can hear it whirrrr.

Easy to check the fuel lines in the tank, simply open the cap and turn on the key and have a look inside. Try easy things first.
Mike
 

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Could be a variety of things but here are a few to check:
1. Fuel Filter clogged.
2. Fuel line split in tank.
3. Fuel pump relay.
4. Fuel pump itself.

The fuel pump should turn on when you turn on the ignition. You can hear it whirrrr.

Easy to check the fuel lines in the tank, simply open the cap and turn on the key and have a look inside. Try easy things first.
Mike
#2 has been very popular lately. It seems as though everyone's fuel lines are falling apart at once.
 

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You have described the symptoms of fuel starvation. First check the fuel lines from your tank to the fuel injectors and check for any kinked lines.

Remove spark plugs and check the condition of the electrodes. They'd have to be obviously corroded away to be the cause of your problem.

My guess, is your fuel filter, which may be located inside your fuel tank. You'll need to empty your tank, disconnect fuel lines, and remove your tank, and then remove the flange that holds the fuel pump and filter. Pretty big job for those not mechanically inclined.

The strategy quoted by Ducatimike takes precedence over what I have stated above. Check the fuel pump actually works, relays/fuses.
 

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Discussion Starter #10
I know that the fuel filter was recently replaced before I took possesion. I do hear the fuel pump whirring .I checked the fuel pump relay by changing it with the fan relay and still nothing. How would i know by looking in the tank if the fuel line was split? I dont see any lines when I open the tank.
 

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I know that the fuel filter was recently replaced before I took possesion. I do hear the fuel pump whirring .I checked the fuel pump relay by changing it with the fan relay and still nothing. How would i know by looking in the tank if the fuel line was split? I dont see any lines when I open the tank.
You can see a lot by shining a flash light into the top of the tank. If that doesn't give you a good enough view, you may have to pull the tank and remove the pump assembly. It's not that bad of a job. I managed to change my fuel filter and got it apart and back together again and I'm not all that mechanically inclined.
 

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What position are you putting the fast-idle lever ?
It can be sensitive to this and from what you afre saying about the benefit of using some throttle this may be causing you some problems.
Try only using about half its travel/if it starts aim to set the lever immediately to give a warm-up speed of 2000 rpm then use that setting in the future when cold-starting and none or minimal if already warm.
 

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You asked about how to know if the fuel line was intact by looking...
With the lid up, turn the key to RUN. Fuel pump should run for about 1 or 2 seconds.

There should be some activity in the tank, because the air separator that's part of the "pump assembly" gurgles a bit and spits out some bubbles. But a whole ton of WHOOSH is a split line. FWIW, it's hard to hear this outside with traffic nearby. I was able to diagnose mine when it was in my closed garage...
 

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If a line was split or loose you would see the turbulence, that pump really cranks out. Check the basics first. Is gas getting to the plugs? You should smell gas on them. If so are you getting a good spark? Are the plugs good? If yes to the above, it's a timing issue.
 
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