Hi,

I am a happy owner of a 907, but my bike doesn't run smooth in city traffic (up to 70km/h). It holds in when I try to drive a constant speed. A lot more when the bike is cold. When air temp is above 20°C it gets less, but in the spring in the Netherlands it is not often so warm. The fuel consumption is 1L:12km. I use the bike daily to work (2x ±30km).
During a service at a duc specialist, they calibrated the throttle vavles and the throttle valve sensor etc (they told me the enigine was much to rich), but it only helped a little bit. I checked temperature sensors, air pressure sensor, battery they look fine to me. I will go back to the specialist (but didn't had time for it, but has anyone an idea what can be the problem.

Oh, I am owning a 907 since end of last year. I had a Paso 906 about 8 years a go. I never got really used to the handling, but the 907 is fine and I like the shape of them.
I still own a Moto Guzzi Lemans 1000 '90; (it will be sold).

Mine's being sorted out at the moment - I'll let you know what the mechanic says was the problem. Sounds similar problem to yours and it's beyond my basic skills...

"FTD", HOW You check your sensors???? :confused: tell more about it! I comment more, after Your answer....

Hi,

The sensors I checked with a multimeter and compared the readings with tables I found by a link on this site. The air sensor I took into the house and checked the resistance at room temp (outside it was around zero degree). The water senor with a cold and a hot engine. I also took the readings from the 35 pin connector. The air pressure was a little more difficult. I used telephonne cable (very thin wire) and place it in the connector and pluged the connector. So I could read the voltage with power on the system. Also compared the volt readings with table/formule I found. I as far as I know this were the right ways, but comment me if it wasn't. (I trust the duc specialist on the TPS).


greetings Frank

PS1 Rogero did you hear something from your mechanic?
PS2 I found something on the mailinglist -title "problem (fixed)"- about synchroning the ignition or coils?. What does/is it exactly. The problem descriped look very much the same.

Rogero,

What was your fuel consumption?
And what is it after the change?

The effect of too rich mixture or too poor mixture look a little bit the same.
Too poor can be caused by leakage between cilinder and filter.

greetings and succes as the wetter is getting better at least in NL

Frank

Ps I will try to make time for a visit at the Duc dealer. To speak a mechanic I needed to do it in the week (not weekend)

Can confirm I rode from Manchester to Liverpool then to Southport then Chester then Cardiff last weekend. Over 450 miles and only filled up twice. I'm getting a very healthy 45 mpg by my reckoning. But I am using Shell Optimax at over £1 per litre! OUCH.

Frank (and others),

The TPS reading is used by the ecu not only to calculate fueling, but also the igninition timing. There are tables in the memory similar to the fuel maps.

Actually, when the TPS calibration is off, the effect of the leaning or enriching of the fuel caused by this will be less than the effect it will have by offsetting the ignition curve. That's why it is so important to have the proper calibration of the TPS.

The reading your mechanic had of approx. 173 mV on the TPS is meaningless in itself. To calibrate it both butterfly valves should be closed and synchronous. The TPS should than be calibrated at 150 mV. After this the butterfly valves are set for idle running etc, toghether with the bypass screws. Because the valves will be more open than at calibration, the voltage will be higher as well. 173 mV could be a good value, but also a wrong one. This will be different for any bike.



Michiel

Michiel,

I agree on what you write (I did read the article of the FIM). When I checked the TPS with the throttle valve(s) closed. At least the screw to set the idle running was complete turned loose. So I assume that the butterfly valves should be closed then (there was a smal tick hearable when the spring closed the valves)

When I have time I will try to do it the complete way as written in the FIM article.

greetings

Frank

Ps but I understand that it is possible to let a 907 run complete smooth trough all the revs?

What most people don't realise, is that there are 2 idle screws (or end stop screws) on the system. There is one on each throttle house. Both should be turned back completely. If the orientation of the 2 throttle housings is the same as on my Elefant (and I believ this is the situation), than one is located on the front left, the other one can be reached by removing the air box :screwy: . After the setup both screws should be set as a throttle stop, but I suggest to use only the more reachable one.....

In fact, by the nature of this system, setting TPS and synchronising the throttle valves (especially around idle with the bypass screws) need to be done all thogether. This because both housings and valves will never be completely identical, and there is only one TPS which is located on the right side housing.
Changeing sync slightly will effect both cylinders but the TPS is calibrated against only one. So this should be checked a few times during setup until a very fine balance is found.

And to answer your last question: Yes, a fuel injected Ducati such as the 907 is able, once setup properly, to run as smooth as a babies buttock from idle all through the rev range, even in gear.
Off course all mechanical parts like valves etc. must be in good condition for this as well.

My Elefant (mind you this is not even water cooled like the 907) used to be setup like this and ran like hell! I've been trying to reach this level of setup myself (my mechanic changed profession 3 years ago so I started do learn it myself the hard way, step by step. I've got it 90% perfect now, so still a bit to go.. (needs a head overhaul)

Michiel

Regret to say that Desmo Dog is absolutely right. With 907's you'll be better dealing with a local mechanic than searching around for a Ducati specialist. I've been severly let down by the franchised specialist and spent a fortune.

My 907 has just been joined by a Triumph 955 Sprint, as I need something reliable and with a good supply of parts as touring on the 907 is becoming more of an adventure than a trip.

I'll never sell the 907 but she's going to be used less and more local from now on. I want to keep her going for as long as possible.

Rogero