New wisdom: snowmobiles go up and down. Snowbikes go back and forth. My buddy was taken out by a sled yesterday (no fault at all on anyone's part--horrible circumstance) and got the lifeflight. Broken ribs, collarbone, scapula, and collapsed lung. He's out for a few months, and if the bumper of the sled had been 6" higher it would have hit his neck and helmet. Sleds and bikes don't really mix--different trajectories.