......I don't know much either, never owned or ridden this model.
According to realoem parts your model only has one sensor but as Razel says, the K1200's have a separate sensor in the cyl head which connects to the ECU and it's the ECU that controls the fan relay.
My 10c of observation:
If the fans come on some time after riding then something responding to heat is probably bringing on the fan relay.
I don't think bulbs have anything to do with it, but if you dropped a wire off the gauge or lost a ground up inside the instrument cluster that might. Get a wiring diagram and trace out the path from the temp sensors to the fan relay.
Are you absolutely sure in the real world that the radiators are running cool. Idle the bike on the stand and feel the tops of the rads when the fans come on - but don't stick your pinkies in the fan! What is the temperature gauge saying. If the stat is ok as you say, then the gauge should be showing a normal temperature if the rads feel hot but not sizzling. Check the wiring diagram 'cos the gauge/sensor and fan switch may be interlinked.
Are you sure you haven't got an air lock? Again feel the point where the temp sensor is if it feels hot but not sizzling your problem is fan control. If that area does feel hot then the sensor may be telling the truth.
Obviously you now have a spare sensor and lets assume your bike only has one (But check the wiring diagram!) . Connect an ohmeter to the old sensor and dip it in frying oil. Heat up the oil from room temperature to about 120 degrees Centigrade and write down the resistance readings every 5 or 10 degrees.
Now hook your ohmeter on the bikes sensor and idle the bike. Assuming both sensors are similar, you should be able to tell us exactly what your coolant temperature is as the bike warms up and at what temperature your fans appear to be cutting in. If sensor temperature is in the 90's (deg C) and heats up very quickly then it is real and you have a plumbing problem. If the actual sensor temperature is below 70 degrees C then you probably have a wiring problem.
Never pay again for live sex! | Hot girls doing naughty stuff for free! | Chat for free!