What island? I've ridden on Molokai. But there wasn't any serious dh stuff there when I was there.
Exposure and focus are great. The eyes are great. But I don't get any feel for the terrain and I think you've framed it too low. It's no the tightness of the composition that's the problem. It's that he's chopped off just above the eyes. If you're going to frame this tight, don't chop the rider's head in half. You can crop through the wheel, but not take off that much head. For mountain bike photos, unless I have a specific composition in mind, I usually shoot a little loose because it's easy to crop later. But if you shoot this tight and get it wrong, there's really nothing you can do to fix it.
