HI, I've got an 07 TE 250 with the Athena big bore kit fitted. It rides brilliantly but have recently been having some minor overheating issues. Even if I take it out for a short ride the cooling fan comes on. This rarely came on before, only in the gnarliest conditions. If you look really hard you can see a very small amount of steam coming from the right hand rad. So minor you can't see exactly where it's coming from but looks like the bottom of the rad. Anyhow more alarmingly the expansion tank seems to be spewing coolant out. Any ideas. I heard somewhere it's possible to fit the head gasket upside down. Could this be the culprit or would that have a different effect. The oil is clean, no signs of water. I'm off for a big ride in a week and desperate to find the problem. There are no off road bike shops on the Isle of Wight.