I had a bit of overheating on my Techno. The bikes starts and runs perfect for about 15 minutes then I start to hear gurgling. I had tested the fan and switch but still overheating. There is a little trickle coming out back of head that is barely noticeable. So I pulled the head off and see a clean spot where I presume coolant has cleared off the carbon. Question is, There are two o-rings for the head/cylinder seal. I didn't see any cuts or deformities on the o-rings or the mating surfaces. The cylinder walls look great and the piston looks fine. The o-rings are soft and pliable. Has anyone seen this happen before? I was expecting more of a problem and am reluctant to think this is just as easy as two o-rings. what do you guys think? Thanks.