If you own a bicycle, an air pump is a must-have.

Regularly checking and maintaining optimal air pressure allows for easier riding and extends the life of your bicycle.

■ How to deliver air and attach to the tube

When discussing types of air pumps, we must first discuss types of tubes.

There are three types of tubes for bicycles.

More precisely, the tube itself is the same, but the shape and mechanism of the valve (the part that allows air in and out) differ.

The "English type" is common on city bikes (mamachari), and the "American type" is common on mountain bikes.

Cars and motorcycles also use this type of valve.

Finally, the "French type" is used on road bikes, cross bikes, and some mountain bikes.

We will explain the differences in detail in another article, but for now, just understand that their shapes are different.

Since the shapes are different, the connection nozzles are different.

Most air pumps come with connection nozzles that can accommodate all types.

They are designed as attachments, allowing you to change only the tip.

■ Pumping air into an English valve

Also known as the American type or American valve.

It is common on city bikes (mamachari).

A "floor pump" that you place on the ground and operate by moving the handle up and down is easy and convenient for pumping air.

It has a cylindrical part called a plunger with external threads and a hole on its side.

A cylindrical rubber part called a "mushigomu" (worm rubber) is attached to it to stop the air.

Therefore, when inflating, you need to press the tip of the air pump against the valve to prevent air from escaping.

Then, by applying pressure, air enters the tube.

The pressure for city bikes (mamachari) is set at around 300 kPa.

For mamachari, it's not necessary to precisely match the pressure, so an air gauge is not required.

In fact, due to the valve structure, an accurate reading cannot be obtained.

For compressor-type air pumps found at bike shops, you use them by pressing them on, but for floor pumps, you attach a clothespin-like attachment to the nozzle (the tip of the air pump hose).

You press the air outlet of the clothespin onto the valve and secure the other end by hooking it onto the cap nut.

Since it's fixed by clamping, you can let go of the valve.

This allows you to concentrate on operating the air pump handle while inflating.

■ Pumping air into an American valve

This type is called American style or American valve.

This valve shape is the same as those used on mountain bikes, cars, and motorcycles.

It is sturdier compared to the English type.

Inside the plunger, there is a spring, and by pressing the central pin called the valve core, air can be let in and out.

For MTB tires, the pressure is set between 300 and 600 kPa.

It is advisable to choose an air pump with an air gauge.

The tip of the air pump connects directly to the nozzle without using an attachment.

For ease of inflation, the floor pump type is easier to use.

If the air pump has low airtightness, air will start to leak as soon as the attachment is fixed, so quick action is required.

The idea is to pump air in such a way that the amount of air going in is greater than the amount leaking out.

However, it is the valve that leaks the least when riding a bicycle, so it also has advantages.

■ Pumping air into a French valve

This is also called the French style or Presta valve.

The French valve is designed to withstand high pressure.

It is mainly used in sports bikes such as road bikes.

Among the three, it is the easiest to adjust air pressure and is lightweight.

It is also the longest, making it easily identifiable.

For road bikes, adjust the pressure to around 500-900 kPa.

Since precise pressure adjustment is necessary, be sure to purchase an air pump with a gauge.

It has a mechanism that prevents air from returning, so loosen the valve core before inflating.

Air will not go in if you try to inflate it as is.

■ There are four units for air pressure

Air pumps may display different units depending on the product.

Most often, two or more units are displayed, but be careful not to under-inflate or over-inflate if you don't correctly understand the units on the gauge.

The four units are kPa (kilopascal), bar (bar), psi (pounds per square inch), and kgf/cm2 (kilogram-force per square centimeter).

All of them represent units of pressure.

For mamachari (city bikes), it's around 300 kPa, for MTBs it's 300-600 kPa, and for road bikes, it's 500-900 kPa. The corresponding pressures are shown below:

300 kPa - 3 bar – 43.5 psi – 3.06 kgf/cm2

500 kPa - 5 bar – 72.5 psi – 5.10 kgf/cm2

600 kPa - 6 bar – 87.0 psi – 6.12 kgf/cm2

900 kPa - 9 bar – 130.5 psi – 9.18 kgf/cm2

The appropriate pressure varies slightly depending on the tire, so check the side of the tire to match the correct pressure.

The recommended air pressure is typically indicated on the side of the tire as "minimum air pressure (min) – maximum air pressure (max)."

When choosing an air pump, make sure to select one that matches your bicycle.