Misjudged the size of his ride...Thought he could fit his bike through the slats on the fence.
Maybe legally blind or depth perception problem...
Watched it three times, pondered it a bit - just couldn't come up with any reason how someone could hit a stationary object he knew was there go'in so fast... Baffled, speechless and oddly amused all at the same time... He looked pretty dazed too.