2009 K1300S -42,000 km. My bike usually runs with 3 bars on cooling gauge and might run up to 4 bars on start-up or heavy traffic. Recently it will run up to 6 or 7 bars ( no warning light comes on)and then it may return to 3 bars or may stay and fluctuate between 6 or 7. Am I correct in assuming a thermostat malfunction or perhaps an other problem???????? I removed the rad plastic and freed up the fan and forced air from the backside (attached photo shows the large amount of crud collected.) This had no effect on the cooling fluctuation. (can't hurt) I am assuming there is a problem and thermostat replacement should correct, comments appreciated.