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I have a 91 907 with 60Kms on in with a high flow air filter and F1S exhaust system. Last year the rear cylinder exhaust valve burnt. At 55Kms, I had it completely rebuild by expert from http://www.mbpducati.ca/ in Montreal Quebec because I like this bike so much. By the way, they are very good and I would recommend them to anybody who is looking for a rebuild or extra power. Now, I drove all summer (5000 Kms) and the rear exhaust is RED all the time but the engine is not overheating. I’ve contacted them and they told me that the valve would last many years/Kms before it burnt again since the new ones were ticker and better then the originals. They are racing/dyno-testing those rebuild engines for many seasons without any problem ever if the exhaust are glowing red and the problem is surely not the engine. So the original problem is still there. First I check the valves, they were O.K. Then I bought a stage 1 EPROM from Ferracci; that was not the problem. I them checked exhaust system and intake manifolds; interchanged the following parts: injectors, spark plugs, spark plug coils, and spark plug coil electronic modules. The engine still starts great and has better power them before. Anybody had a similar problem before? What else can I check? I really want to have this bike on the road again next year but don’t want to spend too much more money on it. I’m thinking the P7 processor.

Check the baffles?
If they're clogged and providing too much restriction, I could see where that might make the pipes hot enough to glow.
Surely, it wouldn't be running as well as expected if this was the case though...
Just a thought.

I would think just the opposite. If the exhaust is restrictive, the flow will drop, and the mixture will go rich. This should lower the temp, not raise it.

If on the other hand the exhaust (or intake) was less restrictive than what the fuel curve was calibrated for, the mixture would go lean, which should raise the exhaust temp. It's also only the rear cylinder, so it's likely something that can be traced to one cylinder.

When you say the exhaust is glowing red, do you mean the pipe itself is cherry red in broad daylight?

Has the cam timing been checked??? How about the ignition timing on the rear cylinder?

That's true DD, you would think it would make it richer, but I've heard of it hapening on cars....if the HOT gases can't excape through the normal egress, the heat's got to dissapate somewhere/somehow. But then, if it was THAT severe of a restriction, it would SURELY be noticable in performance (or lack thereof!) :umm:
But then again, I'm no expert -- especially in the Ducati field!
I was also going to suggest checking the condition of the plug on that cyl to see it is too lean.
Let us know etheriault!

Thanks for all the replies, I’m also thinking about something with the exhaust system but I just don't know how to fix it/prove it. When I say the exhaust is glowing red, I'm taking about the first 8 to 12 inch (23 to 30 cm) of the rear exhaust manifold starting at the cylinder head. The pipe itself looks just fine. I did not look at the manifold in broad daylight but in my garage I notice it was getting red when I started the bike without the fairing after changing oil/filter. The fuel mixture should be OK because with both a Ducati and Ferracci stage 1, I have the same problem. According to the Ferracci web site, a stage 1 EPROM is for use in basic exhaust and air filter mod, which is what I have. I will take a better look at my exhaust system in the next couple of week but as the 907ie have a 2-1-2 system, any problem on the exhaust should be reflected on both sides.

A red hot exhaust pipe is indeed an indication something is quite wrong.

Excessive heat can be caused by a wrong mixture, when the mixture is too lean the combustion temp will rise, when the mixture is too rich the unburned fuel can ignite in the exhaust trajectory (afterburn), also causing a temp. rise in the exhaust.
FYI: if the water temp. sender is defect, the system thinks the engine is too cold, enrichening the mixture to compensate.
If the air temp. sender (airbox??) is defect, the system thinks the air is too hot, leaning the mixture. Both can effect performance and all related effects very much.

It is also possible the exhaust is defect, causing too much back pressure which leaves the hot exhaust gases too long in the system. The heat will dissipate via the exhaust walls.
I can also imagine exsessive heat is caused by a defect in the cooling circuit of the rear cylinder.

My guess is as good as anybody elses, but I'd check the sensors and settings of the efi system very carefully.
Sensor data can be found on my EFI website (see links).

Michiel

Cagiva 905,
Very interesting information, defectives sensor! This is something I did not think about yet. From what ”I think I know on P7 computer”, the only sensors I need to start the engine would be the throttle, timing and position sensors. All others are there to have a better running engine. What would happen if started the engine and having the suspected bad sensor/s unplug. Would this help me in any way in faultfinding my problem? I do not have any diagnostic tools, just a mutimeter.

Cagica 905,

I had to look for it http://www.endless-horizons.net/efi/efi.htm
Lots of information to read about and to think about. I should be busy for a few week, thanks. I will let you know if a find anything Eric

The only diagnostics I have are a multimeter and a digital thermometer (that I still have to bring back to my father in law, hehehe).
I checked the water temp sensor in a cup of hot water, adding colder water all the time, checking the temperature and comparing the resistance with the datasheet.
The air temp sensor can be checked in a similar way, I use an electric paint stripper (hair dryer will work as well, but I'm a man ) and vary the distance.

What wonders me, is that the problem occurs on only 1 cylinder, so I doubt the sensors are the culprit here. I am thinking mechanical problems, like I mentioned exhaust, cooling, or even perhaps a burnt valve (did you check compression?).

From what I'm told, the engine will run only on the rpm and cps sensors, so even without the TPS. However, I've never tried this.
If a temp. sensor is really broken, disconnecting it will not give a difference. If it is only partially defective, giving the wrong signals, a difference in running is noticeable but, so is with disconnecting a proper sensor.

On my bike (Cagiva 900ie Elefant), we once checked the engine diagnostics with a proper tool (we had to put the 907ie Eprom in however to be able to read everything), and it seemed to give all the right readings despite running badly. Only when I noticed the air temp. reading was approx. 10 °C higher than ambiant suggested, we replaced the sensor and the engine ran perfectly. This is a warning not to trust proper diagnostic tools always, checking the sensors like described above is a better way I think.

Michiel

Cagiva 905,
Thanks for the extra info. It will take me some time to be able to check every thing I want to check on the EFI. My garage is not heated; it is already –10C at night and its only December. By Jan/Feb it should be –40C at night maybe more with the wind! I will have to take the sensors out one at the time to the house to do any check on them.

TOO cold for Paso's!!!!! I taught Finnish winter is cold, but You have more - degrees there We have here only -32 at wintertime, but +15...+18 in my garrage, so thats good temp for maintain Ducatis at wintertime, surely battery need to take to cellar and charge some times during winter.

Btw, we tested my 907IE's EPROM to friends Gagiva Elephant GT 900ie, but that didnt function at all.... There are too much differences between 907IE and injected Elephant... totally differend engine and cams and timing, etc....

Anyway You need that ECU tester to check Your ECU. Its easy to make and i think, Youll find, how to make it, if You search from Paso sites... I have one made by myself, but i have seen somewhere good advices to make one..... Sorry, but i dont remember, where...Btw, it can be used also in other Ducati modells!

Antti
Paso 750
Paso 907IE
ST4S

ALL RED!!!!

When you put the 907 eprom in an Elefant, you can use the later model diagnostics to read out temps etc. The engine will indeed not run on that settings.

The old eprom can only be read by the old flashing light diagnostics.
I've got a schedule for that at home, but I cannot find the digital version anymore. I'll look around or make a scan of it.

It could be made for the same price as a Happy Meal (international currency converter

Michiel

When you put the 907 eprom in an Elefant, you can use the later model diagnostics to read out temps etc. The engine will indeed not run on that settings.

The old eprom can only be read by the old flashing light diagnostics.
I've got a schedule for that at home, but I cannot find the digital version anymore. I'll look around or make a scan of it.

It could be made for the same price as a Happy Meal (international currency converter

Michiel

Michiel, You can read ECU problems(sensors, etc...) with that flashing light diagnostic box, NOT EPROM !!!!

Anyway 907 Eprom dont function in IE Elephant. Its tested here.

Ehmm,

That's what I meant actually. My point was that the Eprom in the P7 ECU does not hook up to the later model diagnostics (whit the lcd-screen).
To really read the eprom itself you need yet another set of equipment. I've seen the data from such eproms, and I cannot understand anything of it, unfortunately.

Thanks for the correction, Finnpaso.

Michiel