Hi guys anti freeze pissing out of the overflow when bike heats up, is this a head gasket problem or what else could it be? Also should the fan near the rad be on all the time when bike is started and on center stand.

...but i am hoping not the feared conclusion. I took the bike out yesterday, from a cold garage to an even colder run about 75miles in all. It's not been used for a few weeks, and the last time was just as cold. On my return yesterday I noticed mayonnaise (just a little) on the oil filler...