I went on a nice ride this past weekend and rode some very technical trails. Now in the middle of the summer with no rain, these trails are difficult. This past weekend, I went and rode them after it had snowed/sleet, rained on top of that, then gold cold overnight. There were slick icy/snowy patches all over the place. In one particular section I had a hell of a time getting up a steep slick section. A worn rear tire combined with the tall seat height and tall gearing of my YZ426 didn't help either. I spent about 30 minutes getting up a very technical rocky hill (it's difficult even without snow), and at one point my bike spewed some coolant out the overflow and started running like crap. It kept stalling, sputtering, and backfiring which didn't help getting up the hill. Being relatively new to liquid cooled 4 strokes, are these symptoms of overheating? Is the bike running lean when hot? After I finally made it up the troublesome hill and started moving again, it ran much better. When I made it down the other side of the hill, a pack of quad riders my brother and I chatted with couldn't believe that we were crazy enough to ride bikes in those conditions.