Bikes falls through the grass into space.
Looks like it is on the fence edge.
(http://i.imgur.com/hL0MJp8.jpg)
A little sidenote, hitting the fence in that general area can cause core.exe as well.
+1 !!
I was about to post the same thing (bike falling into deep space at that spot).
Happened to me yesterday night and i was dumb enough not to save the replay ...
The spot seems to be located more or less where the split line is (just to locate it, I don't think there's any causation).
MaX