Those bikes are air/oil cooled and have finned cylinders and heads. If the oil is being cooled all the time, all the more reason to have a highish thermostat rating for the coolant. Let's see what Derek's findings are
Interesting... It would seem silly for Ducati to design a housing and then get someone to make a thermostat to fit it. Much more sensible to design a housing around an existing, suitable thermostat.
The thermostat itself is very similar to any other thermostat, it's the housing that appears specific to Ducati although I'm sure they don't make it themselves and there is every likelihood that a similar one is fitted to something else, not necessarily a bike.
I'm confused. If the thermostat itself is very similar to others, can they not go in the same housing? Sorry if I'm being dim.
Try taking it apart. It's held together with a crimped on metal band. You could probably get into it but you would find it very difficult to put back together again and seal. I just sat my spare in a pot of water and heated it up. It opened at approx 75ºC. It's from an 851/888/907ie but I doubt if they are any different apart from the orientation of the right angled pipe.
The thermostats are manufactured by Behr in Italy. Find a supplier and you might find that there is a range of opening temperature options.
Thanks for testing. My 999 runs at 70 on an open road. Surely it wouldn't to that with no water pumping through the radiator would it?
My MTS runs at 67º-69ºC, so did the ST4s before it. In Italy with temps around 38ºC it ran at about 85º I'm sure the thermostat is open at the UK temperatures because the radiator gets warm but why the running temperature is so low is a mystery to me too
I just realised that the 749/999 has a standard thermostat in a dismantle-able housing that's part of the feeds to/from the radiator. So on that at least you should be able to change it for a higher opening temperature. Not so on other Ducati models.
If the radiator is warm at those low temperatures because the thermostat is open or opening, then surely that is the reason for the motor running at those temperatures.
I wonder if @chrisw would happen to know the coolant temperature at which the ecu stops providing a rich mixture to the motor ??
http://www.ducati.ms/forums/attachment.php?attachmentid=68943&d=1274568567 This is part of a similar thread at ducati.ms about the 748
Noticed this myself over the last few years when doing my annual European trip. I always seem to get better mpg when abroad. Put it down to a couple of things: Differences in the quality of the fuel between here and the continent The fact that the engine stays warmer between start ups plus less stop/starts during the day
This is very interesting... my daily commute is very boring. i use cruise control 90% of the way and i leave before 5am. on my way to work, with CC on and with ambient around 5celsius, i get approx 52mpg over a 75mile distance. on my way home, with the ambient approx 15 celsius and with cruise on, i get approx 60mpg. same journey. these bikes don't respond well (in terms of fuel economy) in cold temps. other bikes i have had have been much more consistent (once warm up is complete)
Update from me...I've not had this or any other duke for that matter very long as I said at the beginning of this.. Went out briefly on mine yesterday evening with ambient temps of around 18 degrees, so warmer than it has ever been for me when using it. The running, open road temp crept up towards 70. Quite lot higher than previous but still cool in my opinion. I reckon Ducati have produced a cooling system designed to cater predominantly for temps in the 30's in southern Europe.. Perhaps we should just go back to the old fashioned method we used on cars in the 70's during winter of covering up half the rad with silver foil!!
As suggested by @Derek, if the water rad is hot at a given running temperature, then that means the thermostat is open and allowing water to circulate through the rad. If that is a low temperature, say less than 85c, to pluck a figure out of the air, then the thermostat is opening too soon for optimum efficiency, both in terms of fuel economy and power. In Italy and other countries with high ambient temperatures, this is going to matter much but for those of us with lower ambient temperatures it could be condemning us to having a motor operating much of the time with a semi permanently enriched mixture. Blanking off part of the rad is one way of dealing with it and is something I have considered. If you were to do it, you'd have to ensure you don't blank off any part of the rad that is used by the fans though or the fans wouldn't be able to control the temperature in traffic. A higher rated thermostat would be a very much more elegant solution...
"A sensor monitors the engine coolant temperature so the computer can supply additional fuel while the engine is warming up, and retard ignition timing when the engine gets too hot. The sensor tells the ECU to stop warm-up fuel enrichment at 180°. So from a fuel correction standpoint, the proper operating temperature is above 180°." The above is an excerpt from a piece on Ducati cooling from 916 owner Shazaam, who is a well known Ducati pundit. I don't think he is infallible but in the absence of other information, this does seem reasonable. 180f is equivalent to 82C . If he's right, lots of us are running on rich mixtures Looking at thermostats, I haven't seen any advertised that open at less than 85c. Given that thermostats are designed to fail open if anything, I cant help wondering if lots of us are suffering from failed thermostats... ?
