Today was around 33, with say 80% humidity?
Took it for a blat over Glorious, most of the time it sat on 83 to 84. the only time it got up in temp was when I was sitting behind a car comming back up the hill, and it got to 89. Once I was around the car, it dropped pretty quick, and the on the trip back down the hill, it dropped down to 79.
The fan takes a little longer to cool in traffic, as it is blowing, but if it comes on whilst you are riding, it is helping the natural air flow, not fighting it as with the stock fan.
I will admit the temp is a little low to what I would like, which is fan on around 95 and turn off around 90, but havent been able to find a switch with the right thread and temp range. I tried a few others before this one, and it did keep the fan on all the time, as it didnt cut off till around 75 (sender stated 85).
Also, I am running synthetic coolant, and I think that helps a lot. I just got tired of frying my nuts and bike in traffic