Well on Elite 150s, a lot of things can actually make them run hot. 11K is not really to much over the regular changing interval, which is usually 7,500 miles, but it is over a bit. Once thing is make sure you fill the little puke bottle to proper level even after you fill the radiator cap and bleed air. Mine was just a little low and my engine ran way hot, and adding a little should make a difference if you have not already. Another thing is that your engine could be running lean due to a number of possible problems. One could, like Kens bike, be a bad exhaust gasket in early failure stages. Mine also did this on a long ride far from my house. The gasket went bad and my engine ran way to hot, just like yours is. It was not doing anything else that Ken's was though, just running way hot. After trouble shooting, I just thought lean usually causes hotter running, and since the gasket causes this, why not pop a new one in. It worked! My engine will idle at traffic lights in 100+ degree weather now all day right below the half way mark! Definitely check this out, as well as your intake manifold, air pipe and so on. If none of these Are your problem, check out your radiator fan, your Thermostat valve, your coolant tubes, levels, and trouble shoot more with the manual. But one tip, make sure when you run anywhere over 3/4, pull over and let it cool for 5-10 minutes before riding back home. Do it even a few times if necessary, as these engines can be damaged easily by this amount of heat. Good luck with your scoot! Feel free to ask any more questions, I know how diffucult trouble shooting can be on these Elites sometimes!