A tire iron is a specialized metal tool

Tool

A tool is a device that can be used to produce an item or achieve a task, but that is not consumed in the process. Informally the word is also used to describe a procedure or process with a specific purpose. Tools that are used in particular fields or activities may have different designations such...

 used in working with tire

Tire

A tire or tyre is a ring-shaped covering that fits around a wheel rim to protect it and enable better vehicle performance by providing a flexible cushion that absorbs shock while keeping the wheel in close contact with the ground...

s that have inner tubes.

Tire irons have not been in common use for automobile

Automobile

An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...

 tires since the shift to the use of tubeless tire

Tubeless tire

Tubeless tires are pneumatic tires that do not require a separate inner tube. Unlike traditional pneumatic tires which use a separate inner tube, tubeless tires have continuous ribs molded integrally into the bead of the tire so that they are forced by the pressure of the air inside the tire to...

s in the late 1950s. The term is occasionally mistakenly used to refer to a lug wrench

Lug wrench

Lug wrench is the U.S. name for a type of socket wrench used to turn lug nuts on automobile wheels. In the UK it is commonly known as a wheel brace or wheel wrench....

, which is included along with a spare tire and jack

Jack (mechanical)

A jack is a mechanical device used to lift heavy loads or apply great forces. Jacks employ a screw thread or hydraulic cylinder to apply very high linear forces.-Mechanical jack:...

 on most new cars.

Bicycle

Bicycle

A bicycle, also known as a bike, pushbike or cycle, is a human-powered, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A person who rides a bicycle is called a cyclist, or bicyclist....

 tire irons are still in use for those tires which have a separate inner tube, and can have a hooked C-shape cut into one end of the iron so that it may be hooked on a bicycle spoke to hold it in place.

Description and use

Tire irons usually come in pairs, or threes, and are used to pry the edge of a tire away from the rim

Rim (wheel)

The rim of a wheel is the outer circular design of the metal on which the inside edge of the tire is mounted on vehicles such as automobiles. For example, on a bicycle wheel the rim is a large hoop attached to the outer ends of the spokes of the wheel that holds the tire and tube.In the 1st...

 of the wheel

Wheel

A wheel is a device that allows heavy objects to be moved easily through rotating on an axle through its center, facilitating movement or transportation while supporting a load, or performing labor in machines. Common examples found in transport applications. A wheel, together with an axle,...

 it has been mounted on. After one iron has pried a portion of the tire from its wheel, it is held in position while a second iron is applied further along the tire to pry more of the tire away from the wheel. This allows enough of the tire to be separated so that the first iron can be removed, and used again on the far side of the other iron. Alternating in this way, a person can work his way all the way around the tire to fully remove it from the wheel, in order to reach the tube that sits inside.

Bicycle tire irons

Tire irons for bicycle

Bicycle

A bicycle, also known as a bike, pushbike or cycle, is a human-powered, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A person who rides a bicycle is called a cyclist, or bicyclist....

s are usually referred to as tire levers, as they are often made of plastic, not metal.

Tire levers for bicycle tires have one end that is tapered and slightly curved. The other end is usually hooked so that it can be hooked around a spoke to keep the tire bead

Tire bead

Tire bead is the term for the edge of a tire that sits on the wheel. Wheels for automobiles, bicycles, etc. are made with a small slot or groove for the tire bead to sit in. When the tire is properly inflated the air pressure within the tire keeps the bead in this groove...

free of the rim at one point, allowing a second lever to be manipulated forward, progressively loosening a larger segment of the tire bead from the rim.

A common feature of tire levers is the lack of sharp edges. The slightest pinch of an inner tube by a lever can weaken or puncture it. It is good practice to examine a set of tire levers for any sharp edges and file them smooth and round. Classically tire levers were made of metal. However plastic ones are now manufactured which are even less sharp and less likely to puncture the tube. There are also some single lever varieties, which can be popped under the bead at one point then quickly pushed around the rim to pop the bead off.

Tire levers are not necessary or desirable in all cases. In some cases, the tire can be reinserted on the rim, and sometimes removed from the rim, without the use of tire levers. This reduces the chance of puncture caused by pinching the tube between the rim and the tire bead. Sometimes they are used to fit the tire back on, but this can be done without the levers.