Bunny Hopping is a technique that is used for maintaining speed. It occurs while holding L and R and pressing B as you come in contact with the ground. To maintain all your speed, you have to jump on the exact frame you land, however, if you are a few frames late you can still maintain most of your momentum. Hopping on slopes can change your direction and speed. Hopping on downwards slopes will cause you to gain extra speed, but less height. For upwards slopes the opposite is the case. Combine this with R-Jumping and dashing to get insane amounts of speed.