How Does Friction Affect Speed on a Skateboard?

Friction and skateboarding do not mix. You need good-working, lubricated bearings to operate correctly for your skateboard move as desired. However, lack of maintenance and bad surface conditions can contribute to problems. The results end up causing the rider to have a horrible skateboarding session or, worse, fall off and get injured.

  1. Basic Friction and Inertia

    • A skateboard is propelled by the rider pushing off on a free foot while balancing his body on the skateboard deck with the other foot. This initial push will generally move the board well at first. However, the momentum of the skateboard will slow down because of rough ground surface conditions as well as the friction on the wheel bearings as they roll. Eventually, the board will slow to a stop if the rider does not push forward again.

    Corrosion

    • Wheel bearings are made of metal. When oxidation occurs from exposure to moisture, the bearings can begin to rust and corrode. As corrosion occurs, grit and rust can get between the bearing rollers inside to cause friction. Over time, the bearings can get so bad that they won't spin easily, if at all. Only very hard pushing on the skateboard will cause the bearings to overcome the friction of the rust inside in such cases. Replacing the bearings in the wheels, however, solves the problem.

    Ramp Design

    • While plywood decks can be used on skateboard ramps to provide a basic surface, good ramp design will incorporate smoother final surface layers made of masonite or similar material. Such surfacing benefits the ramp enjoyment in two ways: it cuts down on the surface friction that occurs when a rider falls, avoiding slivers, and it allows the skateboard to roll smoother. With less resistance from wood, skateboarders can use their momentum and the ramp design to build up speed going back and forth on a half-pipe ramp design. The results can be amazing tricks as the rider gets launched well above the top ends of the ramp to come back down seconds later.

    Road Hazards

    • Skateboards use relatively small wheels in their design. When a skateboard is rolling fast down a street with an incline, it can be prone to wheel lockup if the board's wheels happen to run across dirt or small rocks. If this happens, the rider, who still has the original speed momentum, will fly forward off the board and to the asphalt as the board suddenly gets stuck or slows down. The friction of the obstacle material can cause the board to dramatically move slower than the rider on the board, causing the accident.