can anyone tell me what at what temperature a Ducati (specifically ST2 944ie but I understand many models use the same) thermostat is supposed to open at? Also is there a tried & tested way to check its operation? Prolly not quite as easy as dropping a car one in a kettle and watch it open, as it’s contained in a small T-piece..
I tested on a few years ago by heating it in a pot of water. You can see the valve open through one of the ports. It was about 75ºC which is surprising because most Ducatis run about 69º-70º. There has been some discussion about this on the forum in the past.
That’s interesting as mine seems to run at 67C. Was wondering as the best it’s ever run (no misfiring surging stumbling etc) was on a really hot day 40C ambient with an almost empty tank.
Mine was set to open at 74 degrees for the multi which is the same stat that used on 848-1098-1199 and so on.
That has been the subject of much debate. Detek's experiment suggests that simply replacing like for like will have little effect. If you can find a thermostat from something like a KTM or Aprilia that fits in the same space but opens at a higher temperature, say 80 degrees, it would be very interesting to see what effect it would have on your open road running temperature.
Has yours the oil inter cooler...? If so then can you close that off with the inline oil taps to enable the engine to run a bit hotter?
Ok. Has anyone found a likely candidate from the likes of Aprilia/KTM etc? Always helps to have a part # when looking. But it still doesn’t answer: why would Ducati decide to run so cool when most research shows peak power is usually obtained around 85C?
Yes it has the oil cooler, may give this a try. But doesn’t it impair the lubrication by limiting the oil flow?
Ambient temperatures in Italy are rather higher than here is all I can think of, although the bikes are probably developed on track and on mountain roads where the engine is worked a lot harder.
Yes. My ST4s always ran at about 67ºC here in Scotland where the temperatures seldom exceed 20ºC. When I was at WDW the temperatures were around 38ºC and the bike was running temperatures in the low to mid 80s. Yet even at the lower coolant temperatures we experience in the UK the thermostat is fully opening, evidenced by both the top and bottom radiator hoses getting hot. I haven't been able to come up with a sensible reason why this should be.
