why? as for how it happened: he was side hilling on a little slope on the opposite of the ravine as we always do just fooling around, and the upper ski caught something under the snow and bucked him off and the sled ghost rode down the ravine hitting a tree at the bottom. lucky for him because had it gone another 20 ft it would be in a creek and impossible to get out.
btw this xp 400 miles 1st belt i changed at the 10 hr service just like they all should be changed. sled has ran like a bat outta hell since the first time it fired up. not a single problem.