Parts of a Typical Bicycle Pump
All bicycle pumps share several similar components, even though many pumps may be designed or operated differently. All pumps have a one-way valve. This value allows air to flow into the chamber and does not allow it to flow out of the valve. The one-way valve is the most important piece on the pump because it essentially controls the amount of air inside the chamber and keeps the air flowing in the right direction. All pumps have a piston that forces the air out of the chamber and through the hose into the tire. The piston is connected to the handle, which allows the pump to be operated by the user. Some pumps may have an air pressure gauge, but this is not a necessary part of a bicycle pump.
Valve Types
There are two types of valves used on bicycle tires, Schrader or Presta. Both valves allow air to flow in when a special adapter is placed and locked on top of the valve. This adapter is often found on the end of all bicycle pumps. When the pin in the center of the Schrader Valve is pressed in, it opens the valve and air flows out of or in to the valve. Most thin-rimmed bicycle tires use Presta valves. This is due to its smaller diameter, compared to the Schrader Valve. Many thick-rimmed bicycles, like mountain bikes, use Schrader valves. Whatever the application, both valves hold high pressure and are extremely reliable and rugged.
How a Bicycle Pump Works
The user attaches the adapter to the bicycle valve, and the user can begin pumping. When the handle is drawn up, air flows through the one-way valve and into the chamber. When the handle can go no further, the user pushes down on the handle and the compressed air flows through another one-way valve out the hose and into the tire. The intake valve remains closed while the piston is being depressed. This means the air has no other way to flow but out the hose and into the tire. The second one-way valve keeps air from flowing out of the tire and back into the pump's chamber.
Member Comments