Thought it was a weird one... he had ridden it before (as I understand it) so he knew it went to gravel... maybe it was just that relaxing of concentration for a moment after crossing the finish line and he forgot... whatever it was it is rough for his family and those who tried to save him.
Sometimes your number is up. Although tragic I can only say better to die doing something you love to do, rather than something you have to do. Farewell Bobby.