Bicycle pump

From Freepedia

A bicycle pump is a type of positive displacement pump specifically designed for inflating bicycle tires. It has one or both of the two types of valve in use on bicycles, Schrader or Presta. Basic types available include:

• floor models
• frame mounted
• compact
• 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. Higher-end models have a built in pressure gauge to indicate when the tire is optimally filled.

Using a gas station pump is seldom a good idea. Some are designed to cut off before the high pressures used in many bicycle tires are reached. Some others may pump enough air into the small volume of a bicycle tire in a short time to blow out the tire. There is also a slight difference between the modern standard for Schrader valves on an automobile and that on a bicycle which makes some more recent valves on gas station pumps a poor fit.

External links

Common Types of Valves Used for Bicycles