GoPro Captures A Grizzly Bear Chasing Mountain Biker, but Is It Fake? [VIDEO]

This video has been going around Facebook today.  A guy is mountain biking with his GoPro camera when he sees a grizzly bear charging him from the side.  He pedals harder and faster and manages to escape the bear.   Could this actually be real?

It's hard to say.  If they faked it, they did an excellent job with the digital enhancements.   But I find it hard to believe that hiding behind a tree would trick the bear.  And they don't just scurry off that fast in real life, especially if it was the predator.  He would be sticking around for a while.

What do you think?  Real or Fake?