everytime i have ridden up on a bear i have surprised the bear. it's pretty surprising to you as a rider, but the whooping and hollering sets in and with any luck, the bear moves out of the way.

......Nothing like coming down around a blind corner of a forest service road to find a bear's hind quarters blocking the road and the rest of the bear stuffed in the huckleberries to put a scream in your lungs and a spin in your pedals!