The main reason though is for jumping. When you are a pro, or just a rider who jumps bigs your fenders catch A LOT of air soaring through the sky. The more surface area to grab air is more friction which slows you down and you can not go as far. Also if it is really windy it could really move the quad around awkwardly in the air. For jumping your fenders should be as parral to the ground as possibly. The Air/Wind really affects quads soaring through the air after probalby 70 feet. You can start to tell at 60 feet. Think of how the front fenders cup and catch all that air. Air=Friction which slows you down and will not allow you to jump as far through the air.