I was out of town for two weeks for work and the first thing I did today when I got back was hop on the bike for a 200 mile stretch. I noticed that while going at highway speeds, my temp gauge was not moving at all. It was standing still as if the bike was shut down. The moment I stopped at a light, it started jolting all over the place. It went from cold, to 1/4 to 1/2 temp, back down, etc. It was not smooth transitioning either. Any idea of what could be going on?
A few months ago, I did a coolant flush ANS all was well. Would it be time to replace the thermostat? Fwiw, it's a 95 c-10 with 59k miles on it.