15-03-12, 08:46 AM
Thinking aloud - testing that the fan is operating wouldn't need the complex behaviour of waiting for an initial period then having the fan operate until such time as the bike is put into gear, it would just involve the fan coming on when the engine starts and turning off when the ECU knows it is spinning. Having had a read of the Haynes manual (the owners manual has nothing to say about the fan) the thermostat stops coolant flowing through the system until the engine is at it's normal operating temperature at which point it opens allowing the heated coolant through the system. In the thermostat housing is a switch that operates the fan and temperature warning light. My guess would be that the fan kicks in when the thermostat opens allowing the initial rush of heated coolant through the system. I have no idea why the fan doesn't come on under 1500 rpm I think mine does but when warming the engine I normally have mine sat above this.
Personally I don't have the stuttery / lumpy behaviour when first moving off, I still think this could be caused by carb icing if it only happens in cold weather and is eliminated by allowing extra warming time.
Personally I don't have the stuttery / lumpy behaviour when first moving off, I still think this could be caused by carb icing if it only happens in cold weather and is eliminated by allowing extra warming time.