Pressure in the wheels of a hoverboard: how to measure and what are the standards

How many times a day does it become necessary to pump up a car tire? Not in the same one, although it happens. In general, in all cars, of which there are so many in the world that no one can give an exact figure. And with literally every hour of owners of personal cars, everything increases and increases. Today, perhaps, it is easier to name a country where motor transport is almost absent than those states that already have a car for every family.

Multiplying by four, i.e. for the number of wheels, you can get a huge number. And each of the wheels is not immune to punctures. Or maybe it's all about the nipple. Or the rubber does not fit tightly to the disc. The result is always the same: the tires require pumping up. And if so, then someone who has encountered such a problem for the first time has a question: how to inflate a car tire

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How to properly inflate bicycle wheels: tips from the pros

Driving on flat tires is fraught with many consequences: from deterioration of maneuverability and reduced speed dynamics due to an increase in the area of ​​contact of the tires with the ground, to punctures and damage to the wheels.

In addition, excess pressure promises deterioration in road grip and the risk of tube breakdown.

We will tell you how to inflate bicycle tires, what are the nuances of using a hand pump and whether it is possible to do without special devices.

How to inflate a bicycle tire with a hand pump?

A bicycle pump is an essential device in the arsenal of every cyclist. Its presence allows you to solve the problem of tire pressure yourself, rather than taking the bike to a gas station or service station.

Hand pumps on the market are usually divided into 2 categories: conventional and equipped with a pressure gauge - a special recording device.

For riding on asphalt trails, the recommended pressure is 3.5 atm, for driving on dirt – 2.8 atm.

How to inflate a bicycle wheel with a hand pump: algorithm of actions

1. Place the wheel with the nipple down
2. While holding the nipple tab, unscrew the protective cap and release all the air.
3. Insert the pump outlet pipe into the nipple and unscrew the valve
4. Place the device vertically and smoothly move the rod, pump air into the chamber

Road bikes and some hybrid bikes are equipped with wheels with Presta thin nipples. Such tires require extreme care in handling, as well as a special small-volume pump or adapter for inflating bicycle wheels.

How to inflate a bicycle with a car pump?

Most models of modern bicycles are equipped with a car or “shrader” nipple, which allows you to inflate the tube directly at regular gas stations.

Algorithm for pumping simple wheels with a car nipple

1. Having released the nipple, insert the compressor pipe
2. When using a universal pump, the jumper must be installed with the large end outward in the “auto nipple” position.
3. Close the front cover and connect the pump
4. During the process, monitor the pressure you need
5. How to inflate a bicycle tire with a Presta thin nipple at a gas station
6. First of all, you need to install a special adapter at the output end of the tire
7. Connect compressor
8. When using a universal pump, the jumper must be pointed outward with its thin end
9. Pump several times until the required pressure is reached.

How to inflate a chamber without a pump

Not everyone knows that a standard chamber can be inflated without using a pump. Of course, to achieve optimal tire pressures, a constant flow of air will be required, but the minimum acceptable values ​​are quite achievable. Let's consider several ways:

• Inflating tires using a vacuum cleaner. Many vacuum cleaner models have a blowing mode, when activated, air is not drawn in, but blown out. This function should be used to inflate the tires. A flexible hose can be used to connect the device to the nipple. The more airtight this connection is, the more acceptable pressure indicators can be achieved, therefore, for greater sealing, use any available means: clamps, rubber gaskets, pieces of fabric.
• Bottle compressor. You can also inflate a bicycle using two simple plastic bottles, one of which will act as a rod, and the other as a cylinder. First of all, you need to cut off the bottom of the bottle and use a thin hose to connect its neck to the chamber outlet. Then insert the second bottle into this structure and begin pumping air into the hose through the cylinder. In order to ensure that the junction of the neck and the hose is airtight, you need to coat it with sealant or put a rubber lining of a suitable size.
• Inflating tires with your mouth. This method will help out if the tires are flat and you don’t have anything in your arsenal to pump them up. By removing the nipple, you can inflate a bicycle wheel using the principle of a balloon. However, this is not so easy to do, in addition, there is a risk of releasing all the air while tightening the nipple.

Despite the fact that you can inflate bicycle tires without using a pump, it is better to have this compact and easy-to-use device at your personal disposal. Properly inflated wheels are the key to a comfortable ride without unpleasant surprises in the form of burst tires or punctures.

Affecta Sport provides tire inflation service free of charge as part of any of the bicycle repair services offered.

Let's start pumping up the wheels

Inflating bicycle tires occurs in the following sequence:

• After releasing the tire valve, you need to completely release the air from the wheel.
• A pump is connected to the nipple and the wheel is inflated to the required level.
• During operation, the pump is disconnected from time to time to check the pressure with a pressure gauge.
• At the end, the pump is moved to the side and a protective cap is screwed onto the nipple.

Similar actions are performed with the second wheel. A tire will be considered optimally inflated when the pressure level is approximately 5-8% higher than the value marked on the tire.

The main thing is not to forget to count the number of strokes until the required level of pressure is achieved. This will save you a lot of hassle and effort in the future.

How to inflate a bicycle tire without a pump? It would seem impossible to cope with such a task. However, when you don’t have a standard means for inflating tires at hand, you can use a homemade compressor from a vacuum cleaner with a reverse air injection function. The main thing is to find a suitable hose for this and reliably isolate all connections of the homemade device.

What to pump up

When you have a flat tire, you need to fix the problem urgently.
If this is not done in a timely manner, the stroller:

• becomes poorly managed;
• may tip over on its side and the child will be injured;
• A flat tire will quickly wear out and you will have to buy a new one.

It is necessary to monitor the pressure in the wheels and inflate them regularly.

You can upload:

Hand bicycle pump. They are inexpensive and don't take up much space. Wheels on strollers do not require a lot of pressure and volume of air, and a bicycle pump is perfect for inflation. Most bicycle pumps are configured for 2 types of nipples - AV (auto valve) and FV (french valve). Sometimes they are called Shrader and Presta. 98% of stroller cameras come with an AV or Shrader nipple. When inflating a wheel with a bicycle pump, it is necessary to transform its head into a car nipple. They will explain and show you how to do this when purchasing a pump at a bicycle store. To pump, you need to firmly insert the pump into the nipple and squeeze out the special locking tab. If the pump has a pressure gauge, you should be guided by its indicators; if there is none, just press the tire with two fingers. If the tire is pressed 2-3 mm under each finger, then the pressure is within normal limits.

Floor-mounted bicycle or car pump equipped with a pressure gauge. The pressure required for inflation is indicated in different units of measurement on the side of the tire in Latin letters in Bar, or kg/cm2. You need to determine in what units the scale on the pressure gauge indicates and navigate according to it. If the rim of the stroller is made of plastic, the required pressure may also be indicated on it. You need to carefully examine the inscriptions on the sides of the rim. Sometimes the recommended pressure is 1 Bar on the rim, and 2.5 Bar on the tire. If you don’t notice this and inflate to 2.5 bar, the tire will hold up, but excess pressure can deform or tear the plastic rim.

A car mini compressor that runs from the cigarette lighter. A small compressor that comes with any car. Equipped with a pressure gauge, which is convenient for monitoring pressure, and a flexible hose with a fitting at the end for fixing to the nipple. Energy is consumed from the cigarette lighter.

Professional compressor used for vulcanization

Before inflating the wheel, you must draw the attention of a specialist to the recommended pressure on the tire or rim. They can, out of habit, pump up pressure like a car and damage the rim.

A flat tire on a baby stroller: reasons

Among the main reasons are:

• Puncture of a tire with a sharp object. Most often, the place of descent can simply be sealed. To do this, you need to purchase a bicycle kit with ready-made rubber patches and glue. If the puncture or wear is large, it is better to replace the entire wheel. Experts recommend replacing the entire axle at once. Tires and tires for baby strollers can be purchased at bicycle shops. Before purchasing, it is better to remove the old sample and select a replacement directly from it.
• Non-use of transport for a long time.
• Failure to comply with the rules of preventive maintenance of a baby stroller. Tires should be inflated at least once every 2-3 months.

Why do you need to maintain tire pressure?

Tire pressure is the main parameter that is responsible for the speed of movement, grip on the road surface and the safety of the cyclist. The average minimum value for bicycles is 2 atmospheres. For driving on asphalt, the recommended value is within 3.5 atm, for primers – 2.6 – 2.8 atm.

Determining the pressure inside a bicycle tube is easy and simple using a pressure gauge - separate or built into the pump:

1. Place the bike with the nipple down.
2. Unscrew the protective cap.
3. Install a pressure gauge on the nipple tongue or connect the pump tube to it and tighten the valve.
4. The device will show the current value.

Another method: use your fingers to feel the entire circumference of the tire. If the tires do not sag, then you can drive. It should be noted that this method will give accurate results only for thin slicks on road bikes and tires on city bikes.

Consequences of underinflated tires:

• decreased dynamics due to an increased contact patch;
• force costs to overcome resistance;
• deterioration in bicycle maneuverability;
• punctures;
• wheel damage.

On the contrary, excess air in the chambers threatens the following:

• deterioration of road grip;
• risk of puncturing a tire;
• uncomfortable ride.

Maintaining the recommended pressure will eliminate all these disadvantages and allow you to get maximum benefit and pleasure from your trips. Below is a table of values ​​depending on the weight of the cyclist:

*1 atm = 14.696 Psi

Methods of “pumpless” pumping of chambers

Is it possible to inflate bicycle inner tubes without a pump? It is unlikely to reach the recommended pressure, since a regular supply of air under pressure is required, but it is possible to reach the minimum values. Let's look at several methods of pumping chambers that can be used without using a pump:

Vacuum cleaner. Many models are equipped with a blower mode, when switched to which the air is blown out. A thin hose can be used to connect the wheel nipple. The result directly depends on the tightness of the connection between the hose and the nipple. Here you can use rubber pads, clamps and even rags.

Bottle pump. You will need two plastic bottles. One of them will serve as a cylinder, the other as a rod. Cut off the bottom of the first bottle and connect its neck through a thin hose to the chamber outlet. Next, insert the second bottle into it and pump air through the cylinder into the hose with progressive movements. To ensure a tight seal, coat the connection between the neck and the hose with sealant or install a rubber pad. It will not be possible to create high pressure, but you can ride a bicycle for N distance.

The third way is to remove the nipple and inflate it like a balloon. The method involves difficulties in removing it and installing it in its rightful place. It will be especially difficult to install it back, since during this time all the air can be released.

An alternative to tire inflation is using a bicycle air fork pump. You will have to work hard, since this pump is designed for small volumes.

Despite the fact that a resourceful person will find a way out of any situation, it is recommended to have a special pump for inflating tires. Moderately inflated bicycle tubes are the key to comfortable rides without unpleasant surprises in the form of a burst tube or damage to the wheels.

How to inflate a tire using a hand pump

In general, a bicycle pump is a necessary thing for every cyclist. With the help of this simple device, you will be able to inflate your tires yourself, rather than taking your bike to a service station or gas station.

Hand pumps are divided into two types: simple and with a recording device (pressure gauge). It is recommended to purchase the second option, but if you have a separate pressure gauge lying around in the closet, you can buy a cheaper pump.

Universal hand pump with dial pressure gauge

For the convenience of pumping with a conventional hand pump, you can immediately count the number of air intakes until the optimal pressure is achieved and then pump in exactly this way, even without the additional use of a pressure gauge.

How to properly pump air into the chambers:

1. Rotate the wheel until the nipple is down. You can also inflate the bike upside down or the wheel separately if the bike is being dismantled.
2. Unscrew the cap and release all the air while holding the nipple tab.
3. Insert the pump outlet and turn the valve until it stops.
4. Place the device body in a vertical position and use smooth movements of the rod to release air into the wheel.

Pressure tracking:

• according to the pressure gauge arrow;
• periodically disconnect the pump by inserting a separate device into the nipple;
• check tire hardness.

By the way, it would be a good idea to do the latter with a pressure gauge, since the pressure inside the pump may increase during pumping, but air will not enter the chamber (the valve is not completely closed) or escape through a hole in it.

Common options for bicycle nipples are automotive and Dunlop. For thin wheels, a Presta valve nipple is used. It requires cleanliness and care in handling.

Presta thin nipple cameras are installed on road bikes and some hybrid models

A special small-volume pump is selected for it. A regular bicycle frame may not fit, or you may need to use an adapter.

Car pump - how to inflate tires with it

Most bicycles have a "schrader" or car nipple. The standard option allows you to inflate wheels directly at gas stations and public bicycle pumps (of which there are only a few in our cities so far).

How to inflate simple tires with a car pump:

1. Release the nipple and insert the pump outlet into it.
2. The larger diameter hole is sharpened just for the Schrader valve.
3. On a universal compressor, you will have to install the jumper in the “car nipple” position - with the large end outward.
4. Screw on the top cover and connect the compressor.
5. Monitor the required pressure.

How to pump up Presta with a compressor at a gas station:

1. Install a special adapter cap at the output end of the bus.
2. Connect the compressor to the “car” outlet.
3. If the jock is universal, place the jumper outward with the thin end.
4. Pump in small bursts, gradually reaching the desired pressure.

In this case, it is very important to know exactly how many atmospheres it is necessary to let air into the chambers. If the pressure increases, it can quickly burst.

The last option left is Dunlop. It is identical in size to a car nipple, but its design features are similar to the French one (aka Presta). When inflating a wheel, you should follow the rules for a sports analogue.

How to inflate car tires

Pressure plays the most important role in proper tire inflation.

If you don’t know exactly what indicators are inherent in a particular car, then you can get into a lot of problems. Professionals recommend starting the inflation procedure before the trip, that is, on “cold” wheels. In this state, the pressure in them is optimal and the atmospheric indicators are quite clear.

And if inflation is planned after a trip, then the pressure in heated tires will be higher, this is an obstacle to achieving the correct indicators. Also, some car enthusiasts argue that it is not worth inflating the wheels to the recommended parameters. This is due to the reduced load on the suspension and a comfortable ride. But there are also disadvantages of this method, for example, higher fuel consumption and rapid wear of the outer edges of the tread.

When underinflated, the braking distance of the car is greatly reduced, and this is a good indicator of safety. But the overall controllability of the car suffers in this case. It is also not worth over-inflating the wheels, as this has a detrimental effect on the suspension. While moving, it receives more impacts, and thus its parts fail. And driving on such tires is very inconvenient, there is no comfort at all.

Each manufacturer has its own requirements regarding tire pressure. It also directly depends on the load on the machine. Typically, such parameters are written on the side pillar or on the gas tank hatch.

Optimal pressure at different loads

The greater the weight load, the higher the pressure must be, otherwise the tire will do too much work, overheat and wear out faster, and there will be increased rolling resistance. If you plan to load it into a passenger car, then the wheels should be pumped up a little. This will help maintain good handling, as well as provide fuel economy and extend tire life.

I pumped up 7 atmospheres and went to training

Results of the 60 km training
The cameras, by the way, are constantly being lowered. On a mountain bike - less, on a road bike - more. The thinner the chambers, the more air oozes out of them. There are very light and thin latex bladders - they generally hold pressure for 1-2 days. On my MTB it takes 1 atmosphere in a week, on a road bike it takes 1 atmosphere in 2 days.

This time I decided to pump at the minimum level - 7 atmospheres. I called Fedor - but they took him “for potatoes” - and I went alone on a 60-kilometer circle.

I don't know what played a bigger role. Maybe I was shaking less. Perhaps I recovered normally (2 days), perhaps there was not a very strong wind (13 km/h), perhaps the weather was cool (17 degrees). But as a result, I set a record for the best time on a 40 km section.

Now I have settled on this pressure for now - 7 atmospheres for training. We'll see, as they say.

60 km training schedule

By the way, if you leave 3 atmospheres on a mountain bike (instead of 4.5), then the rear wheel starts to bounce disgustingly (like a ball) and kick into the butt

How much do you pump into your bike?

Alex “On the Bike” Sidorov

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How much does this set cost?

As we said earlier, the cost may vary depending on additional items. The simplest sets cost from 1000 rubles with an adapter and a cylinder. But we advise you to purchase more advanced options, with a pressure control valve - with its help, once you have pumped up the required pressure, you will not waste the leftovers and will be able to use them in the future for the next puncture (the main thing is not to forget to take a spare cylinder on your next trip).

It would also be nice if the adapter was threaded. All the pressure will go into the chamber and not into the environment.

The cans themselves also cost different amounts. As you can see, three cartridges for 16 grams of C02 will cost around 350 rubles. For 25 grams - 750 rubles for three cartridges in a set. Provided that you still need to manage to puncture three times during a cycling season, these pressure stores will last for a long time.

If you want to take it to a more advanced level, here are a few features that can help make the device more convenient to use:

Pressure gauge. So that you know how much CO2 has gone into the tire (this is certainly a convenient thing, especially when you first get acquainted with the device).

A shroud or sleeve to protect your hand and fingers from the cold fitting. Even frost will appear on the metal during operation of the device. You can get a cold burn (frostbite). However, you can operate the device with gloves.

What you need to know about bicycle wheels

In order to accurately measure whether the wheels are sufficiently inflated, you must have a pressure gauge, a special device for measuring the amount of atmosphere in the tires. However, the optimal pressure may vary depending on the type of tire and its manufacturer.

A bicycle tire consists of a tube and a tire. The tire is responsible for the maximum pressure values. Regardless of the tube, the optimal pressure that needs to be maintained in the tires depends on the values ​​indicated on the tire.

Why are you pumping so much?

When I asked Fedor how much he pumps into his road bike, he replied that “about 4-5 atmospheres.”

In response to my 10, he said that I was crazy, and he pumps that much only for competitions. By the way, on my second trip on a road bike, my tube burst (it was pumped up to 10 atmospheres). On the way, I flew into some kind of hole - on an MTB bike I don’t pay any attention to them at all - but here it delaminated along the seam. Well, the camera was extra-light.

There is, of course, another side to the coin. If you inflate the wheels less than what is indicated on the side of the tire, then on some harmful bump/hole/pebble you can “bite through” the tube. The tire is pressed on the edge of the hole to the rim. And the camera bites inside the tire between this unevenness and the rim - and breaks through in two places. In general, you need to look for a subtle compromise option

Fire extinguisher

But this is perhaps the most unusual way to inflate a tire. After conducting an experiment with a large 6-kilogram fire extinguisher, we managed to increase the pressure to a completely ridiculous value of a couple of tenths of a bar. And this despite the spool being turned out. Everything around was covered with a rather nasty powder. Unacceptable!

The average car owner usually has a powder type fire extinguisher in the trunk. A rather large-volume powder fire extinguisher worked extremely poorly. It was not possible to inflate the wheel.

The average car owner usually has a powder type fire extinguisher in the trunk. A rather large-volume powder fire extinguisher worked extremely poorly. It was not possible to inflate the wheel.

How to inflate a tire?

Drivers have faced, and will continue to face, the problem of a “flat tire” more than once. Usually, such a problem falls on you, most often in the morning. You're in a hurry to get to work, you don't have time, and then you get a flat tire. Pumping up is not a problem for an experienced driver, who also has an electric compressor. But for beginners, I will explain this procedure in more detail.

How to inflate a tire? To do this we take a compressor. From it comes a thin wire and a cylindrical tip. We connect it to the cigarette lighter. Then we unscrew the cap and put the rubber hose with the tip on it all the way down, and turn the plastic handle 90 degrees. If you did everything correctly, you can see on the pressure gauge how many atmospheres are in the wheel. It is necessary to inflate to the required atmospheric level, but it is different for each car. This value must be known in advance. Latest actions. We align the plastic handle, remove the compressor, screw the cap back onto the wheel, disconnect the pump from the cigarette lighter, roll it up and put it in the trunk.

How to properly inflate a tire? What is hidden in these words? These words contain only one word - pressure. This value is calculated for each vehicle separately in order to ensure good driving characteristics, ease of operation, and extend the life of tires and load-bearing capacity. The driver should monitor this indicator regularly, especially if you are planning a trip. Upper and lower pressure readings are always given. You should match this data very precisely otherwise:

• If this indicator is exceeded, the smoothness of the ride may deteriorate, dents may form or the tire may be damaged, and contribute to rapid wear of the middle part of the tread;

With reduced pressure, the tires may squeal when turning the car, steering will become difficult, the treads will wear out very quickly but unevenly, especially at the edges, various dents and breaks in the tire rim or tire cord may form, and a fairly high temperature will be created in the tire; Uneven pressure in four wheels also has a very bad effect on the car. There may be uneven braking at the wheels, the steering may be pulled to the side, or the vehicle's handling may generally deteriorate, especially when accelerating or during acceleration.

How to inflate a stroller wheel? This poses no difficulties. You just need to find the pump that comes with the stroller. If it is not included in the kit, then a simple bicycle pump will do. We unscrew the cap, screw on the pump hose, pump it up by hand, remove the hose and screw on the cap. That's all.

But there are situations when you need to pump up a tire, but there is no pump. How to inflate a tire without a pump? Quite quickly, but during this procedure you must be as careful as possible and adhere to all safety measures. Petrol, gas, any spray, alcohol, deodorant or even hairspray will suit us. We inject a little substance into the wheel and set it on fire. The wheel is fine, you can go.

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Inflate to desired pressure

Inflating tires, especially road wheels where high pressure is required, requires some physical effort from you. You can use both arms and legs - straight arm squats can even be used as a small warm-up! But remember, you are pumping your wheels, not your muscles, so keep an eye on the pressure gauge.

After inflating the wheel, remove the hose head from the nipple, tighten the nut and screw the protective cap on top. Your tires are pumped up and you're ready to hit the road! If road conditions require lowering the wheels, unscrew the cap, nut and press on the rod, controlling the pressure in the tire by touch with your other hand. Don't get carried away if you don't have a small pump with you - you can release too much pressure, which increases the chance of a flat tire. And, of course, check the tire pressure before each trip!

What pressure should be in bicycle tires (how many atmospheres)

In this article we will answer the question that many cyclists ask: what pressure should be in the tires of a bicycle? Let us immediately note that tire pressure is the most important factor that affects the cross-country ability and rolling ability of your bike. This is why the tire pressure must be correct.

The required pressure will help you determine the permissible values ​​​​on the tires. All products, regardless of manufacturer, must indicate the minimum and maximum permissible pressure. In rare cases, only one value is indicated - the maximum.

Also, these values ​​can be indicated in different units of measurement: PSI - pressure in pounds (American designation) or BAR - pressure in bars or atmospheres.

A floor or hand pump with a pressure gauge will help you determine the tire pressure correctly. Be careful when using compressor pumps as... they supply large amounts of air at high speed, which can cause the chamber to explode.

Additional tips for choosing the right pressure:

When choosing the appropriate bicycle tire pressure, you should also pay attention to factors such as:

• The surface you are riding on. So, when driving on rough terrain, dirt or sand, it is enough to inflate the tires slightly above the minimum value, this way the grip on the road will be better. When driving on asphalt and flat surfaces, it is better to choose a value close to the maximum - this will improve the roll-up.
• The type of your bike. Depending on the type of bike you have, we recommend using different pressures. For a mountain bike this value should be lower than for example for a sports road bike. The principle here is that the narrower the tire, the higher the pressure in it should be. And vice versa.
• Temperature outside. In hot weather, it is better not to inflate the wheels to the maximum, because... the air in the chamber heats up and the pressure further increases. And in winter, even when driving on snow, the pressure should not be lower than average in order to achieve maximum tread traction.
• User weight. You should inflate your tires more if you weigh a lot or carry a heavy load on your bike.

To summarize, there are no strict rules on how many atmospheres your wheels should have. And the correct answer will be your accumulated experience!

Why do you need to maintain pressure inside your bicycle wheels?

I would like to draw your attention to the following fact. It is almost impossible to overinflate the wheels, since high-quality tires have a fairly high upper limit. Therefore, if you are full of strength and energy, then all the same, excessive efforts will not be enough to break the lids from excess air. The worst thing is to ride an iron horse with flat tires. This can lead to punctures and other damage and subsequent serious repairs or the purchase of a new bicycle tube.

What is written on the tires

The secret to making the right choice is very simple: just look at the inflated tire. Next to the information about the tire size there will also be information about the permissible pressure range in the chamber.

Why is this information not indicated on the camera itself? Because in it the only point subject to real load is the nipple, and its mechanism is very reliable. Otherwise, the normal pressure, which increases by an order of magnitude when riding fast, is taken by the tire, and how much it will be compressed is the main limitation.

So, if the pressure is too low, the tire will break closer to the rim, bite the tube, leading to a breakdown, and if it is high, it may simply burst on one of the bumps or when driving on hot asphalt.

How is blood pressure measured?

Pressure is denoted in three units of measurement:

• Psi – pound-force per square inch – pound-force per square inch;
• BAR – bars, usually equated to a measurement in “atmospheres”;
• Pa – pascals.

Since many tire manufacturers focus on the American market, you can most often find the designation Psi. In English-language sources it is usually simplified to “pound”, or pound, i.e., when they say that a pressure of 2 pounds, they mean Psi. This unit of measurement is outdated, used only in the USA, but, as they say, “more alive than all living things.”

Data from a smart pressure sensor on a smartphone screen

Bars also belong to outdated units of measurement, but are actively supported in Russia and many other countries, incl. European. This unit of measurement is actively used, as it echoes the “atmosphere” that is quite convenient for measurements.

Pascal is the only metrically correct unit of measurement from the list, but is rarely used in bicycle notation.

The relationship between all units is as follows: 1 Bar = 100,000 Pa = 14.504 Psi.

Markings

What do they write on the tires? For example, (2.38-4.0) is clearly atmosphere, or BAR, and (95-135) is Psi. If the number has more than 3 digits or the prefix “k” (kilo), we are talking about metric Pascal. Most often, the desired value is located under the size designation and is duplicated in BAR and Psi in the form of a range, clearly indicating to what pressure it can be pumped.

Actually, the manufacturer indicates by range the limits within which the tire can function, then – the freedom of the cyclist.