Originally Posted by Head2Wind
I believe that running lower engine temperatures than the OEM 75C may not have the intended effect, at least not the same that would result from 160F in a LS1 (Corvette engine, stock ECU and no chip?).... With the LS1, which probably came with a 180 or 195F thermostat, installing a 160F thermostat will effectively trick the ECU into thinking that its still in cold startup mode and therefore will deliver more fuel than it would if it was at "full temp 195".
The thermo switch, that turns on the fans, in the KTM's case, will allow the radiator to get to ~215F before turning on.... so... ~15 degrees sooner is good enough in my opinion. The cycle times get really quick with the Rally Fan kitted bikes and it will only get more rapid if running a lower temp thermo switch. I do not believe that increasing the cycle frequency by lowering the on/off temps below 200F will result in better cooling efficiency or effective heat transfer, nor do I believe that a lower engine temperature will result in much either. Again, this my opinion, not based in testing and fact finding.
The 160F Stat in the ls1 is for use wit the mod ecu ls1edit to say one of then and the intent is for advance the timing more and avoid pre-detonations then the ecu is mod to start the fan at 160F too and avoid high temp at idle or traffic.the need to the engine to run at 200F is by much for the environmental purpose, cat MPG etc.
Since the 990 come wit the 160F stat and wit the 220F sensor if the 990 is cruising at 60 MPH maybe the fan never start but the Stat will open at 160F and the engine is supposed to run like this from factory and dont make any harm to the engine then when the 990 stop or in traffic the temp in the radiator will go to 220F to make the sensor start the fan at this temp, if we low the sensor to 160F to start the fan sooner this will be like the 990 is still cruising and maybe this will help the jerkiness preset when the engine is hot, this will be nice to run the 990 without get the legs burned or our lady ass melted
BTW I dont pretend to hick-jack your product I think is the best solution for our 990 Thanks.
PD your setup works wit the 5.2" fan too?