With about 6 hours on the bike I rode through a recent forest fire. The trail disappeared and basically had to cut our own through a foot of ash that had gotten rained on. I was in first for basically a 3 mile steady climb through this stuff. Towards the top I noticed steam coming off my header pipe from where the radiator over flow tube was draining and hitting it. This went on for about 10 minutes before I was able to stop and let it cool down. I ended up losing a couple ounces of coolant when I checked the next day.
Here is another thread I made with some pics of the cylinder head and spark plug. Not sure if anything in there would indicate damage from overheating, again I dont have a ton of experience so not sure exactly what I?m looking for.
http://www.gasgasrider.org/forum/showthread.php?t=23926