Hi all. I have a weird overheating issue with my MP3 500. For normal riding around town and under 65mph temp is fine, gauge is in the middle (our even below) and will stay there all day. However, if I ride at over 65mph for more than a few mins the temp begins to climb and heads to red zone. If I slow down to about 5k rpm it settles back down to middle of the gauge.
I've drained the coolant and bled the system - based on volume of coolant I put in I think there's very little if any air in there. I've watched the level and its not leaking or losing coolant either. I checked the impeller on the water pump and this also seems to be fine - I had thought it may be worn and was cavitating at high speed. I read somewhere that someone suggested it could be the thermostat allow the coolant to flow to fast around the engine at high speed and not allow enough time to properly cool.
Any thoughts? Weird problem and is annoying to be stuck at <65mph