2. WHY AN OIL THERMOSTAT?
The specification of the oil cooler was to control the oil temperature to a maximum temperature of 85ºC (185ºF) under conditions to occur simultaneously of:
a) An ambient air temperature of 52ºC (125ºF)
b) WOT (Wide Open Throttle)
c) Running in conditions of a) and b) to thermal equilibrium (by testing reckoned to be 10-15 minutes).
This combination of conditions is very extreme. The vast majority of triple riders these days do not run flat out for 10-15 minutes continuously - never mind in an ambient temperature of 125ºF!
So for the vast majority of the running life of the engine the cooler in the standard configuration overcools the oil. This can lead to the water condensate in the oil never being driven off as the oil does not get hot enough. The condensate can cause bearing corrosion and cause "mayonnaise" in the cooler parts of the engine and the low oil temperatures mean a lengthening of engine warm up times.