Ducati Sporting Club UK > Model Specific - Discussion, Technical Problems and Help > 999 / 749 > What does this sound like?

[JPM]

Should be a warranty job really as it's quite a common problem, got to be worth a try

[Murray Mint]

Talked to a guy today and he's of the opinion that it's the throttle bodies that are out, anyway she's going in for service soon so i'll find out then.

Murray Mint

[Murray Mint]

Quick update.

So I’ve replaced the front coil, still not right. Replaced the spark plug, still no joy. Removed air tubes to observe injectors, seems like there’s plenty of fuel getting delivered, thanks for the tip Nelly. Funny thing with this is that if I hold the throttle open at a steady 3k Revs and above then things seem fine, I haven’t tested this on the road yet and doubt that I will as I’m not that keen on the idea.

Does this sound familiar to any of you guys?

Murray Mint

[HW]

Yep ... not always the front coil, as I know from first hand experience. The rear one is also susceptable, especially if you wash the bike often with it on a paddock stand. The top of the roker cover is dishe and water pools there and works it's way into the coil tube.

To get to it is not hard ... but you need to lift the seat/tank unit to the extent that the fuel pipes will let you then you can work the coil out. You might find it is wet and rusty in there.

Note: Watch out for the left hand fuel pipe when refitting the tank, as it can get trapped on the top of the rocker cover bolts. If you prod it then it will fall into the recess provided for it in the bottom of the tank. In fact, it could well be this that is causing you grief if you have had the tank off recently?

[guest1]

If you can (and I don't know how without taking the fuel system off the bottom of the tank) check to see if there is any crap in your tank such as sand/grit.

[Gizmo]

I've had the rear cylinder misfire exactly as Henry describes. Check rear coil and plug

[HW]

When I first joined the (not so exclusive) One Spark Club, I determined that it was the front cylinder that was playing up. The evidence was pretty convincing because after starting at a local bike meet on one cylinder and riding down the road hoping it would clear and start firing, I stopped and found that the front pipe was cold. Got home, pulled the coil out (for the first time by me in it's 18 moth life) and it was wet and rusty. Cleaned and replaced and it seemed fine. Italia Moto in Lincoln recommend red rubber grease around the seal to help keep water out, and a spray of silicone stuff (Wurth) in the cap end and in the plug. The plug on that one was on the old type, fixed to the coil.

I have since had trouble with the rear cylinder, repeatedly, and having swapped one coil under warranty I now have the new type with flying lead to the plug on the front so the plug sits around the side bhind the fairing, and the old rusty one in the rear cylinder. That is working at present. The (not so) rusty one from the rear turned out to be faulty, based on swapping the coils around and some long term tests.

[Murray Mint]

OK guys, changing the rear coil was going to be one option but it did'nt seem like the way to go bacause it is the front cylinder thats giving me the problems. Who knows, stranger things have happened at sea (or so they say) whoever THEY happen to be.

[HW]

How are you sure it's the front cylinder? Short of the pipe not being as hot as the rear one I couldn't tell for sure. I just read your posts again and unless I missed something I cannot see where you give any clue why you are sure it's the front one?

[nathanhu]

i would check the cables behind the oil cooler fairing as they do chafe(sp)

and also the contacts inside the main wiring loom plug to the coil.