The main component of a bike pump is its barrel. This cylindrical tube is usually made of steel or aluminum and serves as the chamber through which air is pumped into the air hose and bicycle tire. Floor model pumps include a base at the bottom of the barrel to keep it stable while pumping.
The plunger is the long, solid tube that fits through the barrel. The top of the plunger features a handle sticking out the top of the barrel. The bottom end of the plunger often includes a spring so the plunger bounces up for easier use. Smaller, traveling bike pumps will usually not have a long handle sticking out from the plunger but will instead have a handle directly above the pump head that lies flush against the barrel.
An air hose snakes from the side of the barrel to carry the air from the barrel to the bicycle tire. The hose is flexible and usually made of a woven cord. Hose lengths can run up to 20 inches long. Most hoses are detachable, with a coupling on one end that screws into the pump's barrel and makes for easy replacement. The other end of the hose features a pump head.
The pump head is the attachment that connects the hose to the tire valve to fill the tire. The seal is made airtight by either screwing the tip of the head onto the valve or closing the small lever attached to the back of the pump head. Some pump heads can be screwed off to change the type of adapter inside it so it can work with both Schrader and Presta tire valves. If that's the case, the pump head components will include the adapter, a rubber washer and a removable valve cap. Other pump heads are permanently affixed but can still hold a number of adapters.
Bicycle pumps may come with a number of other parts, depending on the type of pump you purchase. An air gauge is a common feature to instantly check the tire's air pressure and avoid over-inflation. Adapters for the pump head are also popular. Needle and cone adapters work to fill balls and other sports equipment. Pumps may also include a clip that keeps the hose in place when not in use.
Article Written By Ryn Gargulinski
Ryn Gargulinski is a writer, artist and performer whose journalism career began in 1991. Credits include two illustrated books, "Bony Yoga" and "Rats Incredible"; fitness, animal, crime, general news and features for various publications; and several awards. She holds a Master of Arts in English literature and folklore and a Bachelor of Fine Arts in creative writing with a French minor from Brooklyn College.