Damn this looks scary as hell. The uploader claims either the rider lost consciousness or there was a problem with the bike.

http://www.youtube.com/watch?v=pKdF0Z4OB8I

that was scary stuff.

Mmmm. Looks more like a rider problem to me. You can spot the erratic riding a fair bit in advance of him hitting the grass bank. Tiredness perhaps? Either way, nasty.

weird - you think the rider maybe had a drink and got drowsy

used to have a moderate drink every now and then but leave it now although never felt in danger of falling asleep