Bicycle Pump

A bicycle pump is a type of positive-displacement pump specifically designed for inflating bicycle tires. It has a connection or adapter for use with one or both of the two most common types of valves used on bicycles, Schrader or Presta. A third type of valve called the Woods valve exists, but tubes with these valves can be filled using a Presta pump.

Several basic types are available:

• Floor models or track pumps
• Frame mounted
• Compact or mini
• Foot operated
• Double action

In its most basic form, a bicycle pump functions via a hand-operated piston. During the up-stroke, this piston draws air through a one-way valve into the pump from the outside. During the down-stroke, the piston then displaces the air from the pump into the bicycle tire. Most floor pumps, also commonly called track pumps, have a built in pressure gauge to indicate tire pressure.

Electrically-operated pumps intended to inflate car tyres (as available in most service stations) can in principle be used to inflate a bicycle tyre if the right type of connection is available. Some such pumps are designed to cut off before a suitable pressure (much higher for a bicycle than a car tyre), and will much underinflate the tyre. Others may not cut off, but deliver a high rate of flow to fill the larger car tyre, with a risk of overinflating and bursting a bicycle tyre unless it is stopped with split-second timing.