## Tire measurement using the ISO method

**Find**out if your tires are NOT ISO measured instead of the conventional method. The ISO system uses millimeters to determine the dimensions of a bicycle wheel. If you do not have a tape measure to measure a wheel in inches, just know that there are 25.4 millimeters in one inch and use a calculator to multiply the width by 25.4.

Make sure the bike is placed against a wall or on a stand. Measure in millimeters from the center of the wheel to the inner edge of the tire. Twice the resulting number to calculate the diameter. Most ISO-measured tires for adults are 650 to 700 millimeters in diameter.

Measure the tire width in millimeters. Use the recommendations above for tread measurement. Remember that tires of different widths can be used on the same bike if the difference is NOT too drastic.

**tire**, remember that width comes first, followed by diameter. For example, a 53.3 x 700 bicycle wheel has a tread 53.3 mm wide and 700 mm in diameter along the inner edge of the tire.

## The most common **bicycle** wheel rim 26 (photo)

Without a doubt, this **size** is the most common in the world. In millimeters, its diameter is 559.

These wheels are used mainly on most adult mountain, walking or urban species.

SEPARATE CASES 26 ” Bicycle Wheel Rim Fitted on Chinese Mountain Teens Models.

It should be noted that on most types of “iron horses” for adolescents and adults, rim (V-brake, tick-borne, hydraulic, cantilever) or disc brakes are installed.

In this regard, wheels of the 26th size differ among themselves in compatibility with their different types.

As a rule, a separate model has been developed for each of them, as indicated in the title. For example: **bicycle** wheel rim 26 (under V-brake) or 26 (under Disc).

## Bicycle tire markings

As mentioned above, in the classic version, the marking is applied to the side surface of the **tire** in the following sequence:

- Diameter in inches.
- Width in inches.

The standard marking looks like 20 / 1.75.

In the case of ISO marking, the sequence looks different:

- Profile height in millimeters.
- Rim diameter in millimeters.

The wheel will also look like 44.4 / 406.

For successful operation of the bike, you should use only tires and tubes recommended by the manufacturer. The fact is that tires that are overly narrowed from the normal **size** are prone to more frequent punctures, and too high a profile will provide noticeable resistance when driving and be damaged more often. Use only the correct tire sizes and enjoy a pleasant cycling ride.

## How to determine the size of the wheels of a car

The same calculations are carried out on cars. For example, to calculate the size of the VAZ-2114 wheels, you need to take data from the marking of a standard tire (175/70 R13). These parameters show that the width is 175 mm and the height of the tire is 70 percent wide. In this example, the height is 175 0.7 = 122.5 millimeters. R13 = 13-inch rim **size**. To calculate the total wheel diameter By summing the tire profile height and the rim diameter, we get 1324.4122.52 = 575 mm. This is the standard full diameter wheel **size**.

## What are the sizes of bicycle wheels?

Wheel sizes depend on bike models, their intended use and the age of the owner. So, for children’s and teenage bicycles, sizes up to 20 and 24 inches with a wheel size of 508-609 millimeters are characteristic. Special bicycles, the so-called mountain bikes, have a wheel size of 26 inches and 660 mm. General purpose bicycles are road bicycles, often equipped with wheels of 28 inches and 711 mm. We should also highlight the category of mountain bikes, with a large size, they have 29 wheels. What is the size in millimeters? That’s right, 736 mm.

To calculate how much a 16-inch wheel will be in centimeters, you need to multiply this value by 2.54 and you get 40.64 cm, and a 10-inch wheel, how many cm? 10×2.54 = 25.4 cm!

Below are the wheel sizes for children’s bicycles.

The dimensions of the wheels of bicycles for a child are most often the following dimensions:

## Diameter and radius

The very first question is how to measure the diameter of a **bicycle** wheel? There are several proven ways to measure the radius or circumference of a tire. To measure the radius, place your vehicle level and, to avoid injury. Secure it with a footrest. Then attach a tape measure (it is better to take a metal or wooden ruler, elastic centimeters can give an error when stretched) with one edge to the ground, and fix the other near the sleeve on the axis. Thus, we measured the radius, multiply by 2 and get the diameter.

## How to **find** out the radius of a wheel on a **bicycle**. What does the wheel consist of?

First of all, it is worth learning about the construction of a bicycle wheel. Regardless of its type (mountain, urban, sports, etc.) The device of this part is identical.

- Hub (bushing). It is located in the center of the wheel and rotates around a fixed stationary axis on bearings. The ends of all the spokes are attached to it.
- Bicycle wheel rim. This is the metal circle to which the second ends of the spokes are attached, as well as the tube and
**tire**.

**Bicycle tire markings**

It comes in several types. The confusion in size designations began in the middle of the 20th century, and even today the UK and France use their designations for marking.

Previously, the sizing system was based on the outer diameter of the tires. It was measured in inches (24 “, 26”, 28 “) or in millimeters (500, 650, 700, etc.).

Over time, this system has lost its meaning, because K. In different products with the same outer diameter of the wheel (together with the height of the tire), the inner diameter (rim landing diameter), on which this tire was worn, did not coincide. This is also superimposed on the marketing moves of manufacturers, and the accuracy of translation and rounded measurements in inches is lower than in millimeters.

To overcome THESE confusion and bring all sizes to one standard, the International Organization for Standardization (ISO) has developed a universal system for designating **tire** sizes. **ISO 5775**. This system was previously known as ” **ETRTO** “. It was proposed by the organization of the same name: ETRTO (European Tire and Rim Technical Organization or in Russian: “European Technical Organization for Rims and Tires”).

### The article will address the following issues:

**Types of bicycle tire markings:**

## Bicycle tires: sizes, types of markings and interchangeability

Sooner or later, almost every BIKE is faced with the question of replacing the rubber on the wheel or cameras for them.

The easiest way, of course, is to look at the **size** of the tire currently installed on the bike (it is written on the side of it), and look for exactly the same one. Some rims also write their landing diameter and width.

In life, everything is always a little more complicated and it often happens that the tires you like have a marking that is not entirely clear or does not coincide with the markings applied to your rubber. Sometimes you need to replace an old bicycle rubber that has served for many years with a more modern one.

What to do? On the Internet, you DO NOT put tires on the bike, but pays money just yes. I don’t want to.

In this article, we will try to help you understand the markings on bicycle tires, and **find** out which ones are interchangeable.

## Bicycle tire sizes: what are they and how to choose the right option?

There are many reasons people buy a bike. Regardless of the purpose of this vehicle, its most important element is tires, which often have to be changed. What they are and how to choose them correctly, you can **find** out from this article.

**The problem of indicating the size of tires in inches as a simple and decimal fraction**

Pay attention to a very important nuance and paradox in the sizes indicated in inches. Tire sizes can be specified as a decimal fraction, for example 26×1.75, or as a simple fraction, for example 26×1 3/4.

Mathematically, these fractions are: 1.75 = 1 3/4.

But, from the point of view of the landing size and width of the tire in millimeters, this is not always the case, and what is most unpleasant is that tires with such dimensions can be **NOT interchangeable**.

And this circumstance must always be taken into account when purchasing a new bicycle rubber.

**If the tire is narrower than the rim:**

- The likelihood of punctures is significantly increased
- Rim damage may occur

## Types of **bicycle** tire markings:

- Marking according to ISO specifications (ETRTO). The most accurate, understandable and user-friendly. Describes all required dimensions in millimeters. For example, 28-622, where 28 mm is its width and 622 mm is the inner (landing) diameter.
- Fractional inch marking, type 28 × 1 1/8. Where: 28 is the outside diameter in inches and 1 1/8 is its width in inches (one point and one eighth of an inch).
- Inch decimal notation. For example: 26×1.75. Likewise: 26 is the outside diameter in inches and 1.75 is the width. What is the difference between simple and decimal fractions in THESE designations, and what problems this brings, we will talk below.
- Designation of sizes in the form of several numbers in inches: 28 x 1 5/8 x 1 3/8. Where: 28 is the outer diameter in inches, 1 5/8 is the height of the bike tire in inches (one point and five-eighths), 1 3/8 is its width in inches (one point and three-eighths).
- French markings. Here it is less common, however, on wheels made in Europe or for Europe, it is often applied.

At first, it was in the form of a number and a letter, for example, 700C. 700 the outer diameter of the tire in mm. The letter determined the width from “A”. the narrowest in “D”. wide.

Now the marking has acquired a more modern look. For example: 700 x 35C. Here the outer diameter of the tire is 700 mm and its width is 35 mm. The letter at the end indicates the inner (landing) diameter. In this case, “C” is 622 mm.

**tire**(rim fit) is 533 mm, and then its width is 37 mm. (Instructions for Soviet bicycles “SPORT“, “Salyut”)

**Bicycle Tires: SIZES, TYPES OF MARKING AND INTERCHANGEABILITIES**

Sooner or later, almost every BIKE is faced with the question of replacing the rubber on the wheel or cameras for them.

The easiest way, of course, is to look at the size of the tire currently installed on the bike (it is written on the side of it), and look for exactly the same one. Some rims also write their landing diameter and width.

In life, everything is always a little more complicated and it often happens that the tires you like have a marking that is not entirely clear or does not coincide with the markings applied to your rubber. Sometimes you need to replace an old bicycle rubber that has served for many years with a more modern one.

What to do? On the Internet, you DO NOT put tires on the bike, but pays money just yes. I don’t want to.

In this article, we will try to help you understand the markings on bicycle tires, and find out which ones are interchangeable.