Table of Contents

### By calculation

The required value can be calculated using the formula, knowing the diameter of the tire. The **diameter** can be indicated on the tire itself or determined using the previously described method. The circumference of the wheel is equal to the product of its diameter by the number Pi: C = D π. Unit of measure **inches**.

For example, 20×3.14 = 62.8 “, where 20 is the diameter of the tire in inches, and 3.14 is the pi number (constant).

### Tire width

Measurement, as in the above case, is made with a tape measure. It is placed on the tire perpendicularly and the distance from one edge to the other is measured. The tape should be held strictly horizontally (that is, across the bike tire) so that the result is as reliable as possible.

The width of a **bicycle** tire purchased to replace a damaged one may slightly differ from the original one (be slightly wider or slightly narrower). This fact will not affect the ability to install it.

## How to measure the diameter of a bicycle **wheel**?

When you need to replace a punctured tire or purchase a spare tire, it is important to know the diameter of the bicycle wheel. The marking can be viewed on the currently installed bus. It is printed on the side of the tire, and indicates its diameter and width. If the numbers are erased or the inscription is not readable, you can measure the diameter of a bicycle wheel yourself using two simple methods.

## Wheel circumference

This value is no less important than the previous ones. After replacing an old or damaged bicycle tire with a new one, you need to adjust the exact operation of the instruments (speedometer, odometer, navigator). To do this, the size of the circumference of the wheel is entered into the cycling computer.

You can find out this parameter in several ways.

## Standard measurement method

To determine the diameter, you first need to know the radius of the wheel. Knowing the latter, you can calculate the **diameter**. According to the mathematical formula, the diameter of a circle is equal to two radii: D = 2 r.

### With an inelastic cord

To do this, pull a thread, cord or cable around the bike tire. Its thickness does not matter, the main thing is that it fits snugly against the rubber. Next, you need to make a mark at the place of its contact with the initial end. Then remove the cord, spread it on the ground and use a ruler (tape measure) to measure the distance from the starting end to the marked mark.

### Wheel diameter

The measurement is carried out as follows: a measuring tape is applied from the ground to the center of the sleeve on the wheel axis. This will be the radius of the wheel. Since the bushing is an order of magnitude wider than the wheel, in order to reduce the error, the measurement should be carried out strictly vertically. The tape must not run along the spokes of the wheel being measured.

Further, the found radius in cm is multiplied by 2. The calculated number is the diameter of the wheel. To convert units (centimeters) to **inches**, divide the product by 2.54 (1 ″ = 2.54 cm). For example, the found distance is 34.2 cm. Multiply this number by 2, divide by 2.54 and get 26.929.

If the calculation results in a non-integer number, the total is rounded to the accepted standard wheel sizes in inches. In the described case, the wheel diameter will be 27 ″. Bicycles for adults often have wheel sizes ranging from 26 “to 29”.

[attention type = green] Tip! When taking measurements, it is better to use a wooden ruler or a rigid metal tape measure. The elastic tape can stretch and distort the result. [/ Attention]

## Tire marking

The classic system of standards involves marking the tire in this order: the first number indicates the diameter of the tire, the second. the width. The standard units are inches. For example, the entry 29×2.00 says that the tire **diameter** is 29 “(or 73.66 cm) and the width is 2.00” (or 5.08 cm).

It should be remembered that the marking of bicycle tires according to the international ISO standard has a different form and unit of measurement. millimeters. So, first the value of the wheel width is applied to the rubber, and then the diameter. For example, the inscription 40×700 means that the tire has a width (width) of 40 mm, and its diameter (diameter) is 700 mm.

## Dimensions of **bicycle** wheels 1

A bicycle wheel is a part of a bicycle structure that consists of a tube, spokes, hub, rim and tire.

The wheel must be well balanced and dimensioned to certain standards.

To begin with, you should pay attention that the diameter of a bicycle wheel depends directly on the thickness of the bicycle tire and the diameter of the rim. Most often, the wheel size is indicated in English inches, because the dimensions of the tire, rim and tube must comply with international standards.

Today, there are 6 most common bicycle wheel sizes, which also directly indicate the radius of the bicycle wheel:

- 20-inch wheels (the rim is 406 mm in diameter). fit on children’s and folding bikes, as well as on BMX models;
- 24-inch wheels (507 mm rim in diameter). for extreme sports bicycles and teenage models;
- 26-inch wheels (559 mm for rim diameter) are the most common bicycle
**wheel**size. They are equipped with city, walking models, as well as mountain bikes; - 27-inch wheels (rim in diameter. 622 mm). designed for road bikes;
- 28-inch wheels (rim diameter also 622 mm). for road and hybrid bikes. Many Soviet models are equipped with such wheels;
- 29-inch wheels (also 622 mm in diameter) are a relatively recent standard for mountain bike
**wheel**sizes. The popularity of this particular model is just beginning to gain momentum.

Note that the dimensions of the last three types of bicycle wheels have the same rim diameter, the difference is only in the thickness of the tires. Accordingly, the standard and most common bicycle wheel radius is 311 mm. In order to determine the circumference of a bicycle wheel, you need to do a little test yourself on your bike.

You need to sit on a bike and drive a short distance, while trying to accurately record the moment the surface touches a certain point of the wheel. Then you can simply measure the distance from the first such point to the second and, in accordance with the result obtained, determine the circumference of the wheel

In order to determine the circumference of a bicycle wheel, you need to do a little test yourself on your bike. You need to sit on a bike and drive a short distance, while trying to accurately record the moment the surface touches a certain point of the wheel. Then you can simply measure the distance from the first such point to the second and, in accordance with the result obtained, determine the circumference of the wheel.

All these manipulations are necessary for the correct selection of tires of the desired size. Guided by the above simple data and tips, you will better understand your bike and be able to equip it accordingly.

## Circle

The second required dimension is the circle. There are several surefire ways to measure the circumference of a bicycle’s rim:

- We take a non-elastic thread, wrap it around the top of the rubber. We lay it out exactly on the surface, take a ruler and op!. we get the length of our tire.
- From the course of school mathematics according to the formula: circumference = πr 2.where π is a constant number 3.14, and r is the radius (the method of measurement is above).
- With a drop of paint. Place a dot on the tread, then run your bike on a level mowing line and on a smooth (eg asphalt) surface. The point will be printed twice, the distance between them will be the circumference.

## How to find out the diameter of a bicycle wheel. the standard method

Finding the size of a bicycle wheel is easy enough.

- vehicle (bicycle);
- calculator;
- roulette.

First, you need to determine the radius of the bicycle wheel. Only after that it will be possible to determine the size. You can determine the radius using a special calculator or using the formula.

On the Internet, you can find all the basic formulas for determining the radius. We recommend using the following formula: D = 2 r.

## What are the sizes of bicycle wheels?

The geometric parameters of bicycles differ according to a strict pattern. this also applies to the size of the frame and the diameters of the wheels. First, let’s present a size chart:

20/508 406 Children, teenage, folding, BMX 24/609 507 Teenage, folding adult 26/660 559 Mountain 28/711 622 Road, hybrid, road 29/736 622 Mountain 29er

### How to Measure a Bicycle Rim and Hub

The first column shows the traditional wheel diameters in inches and millimeters. The wheel is measured with the tire. To find out the size of the rim, you need to subtract the height of the tire, multiplied by two. Standard rim sizes are shown in the second column.

Bicycle wheel measurement systems:

- classic, in inches;
- in centimeters;
- ISO standard, in millimeters.

The International Organization for Standardization (ISO) has implemented a universal wheel measurement system to avoid confusion. All bicycle manufacturers adhere to it. The dimensions of the wheels are made up of the **diameter** of the “clean” rim and the width of the tire profile.

When choosing new tires, you need to know the rim landing diameters. these numbers on the tires must correspond to them. This will come in handy when changing to a different tire profile. In everyday life, a wheel is measured in **inches**, and it is more convenient to give dimensions in inches. And by the size of the wheel, you can also determine the type of bike. walking, mountain or road.

Wheel sizes are important to know when choosing a child’s bike. There is a direct relationship between the numerical values of the diameters with the height and age of the child, the so-called “wheel size”. Below is a table of standards:

Diameter, inches | Height, cm | Age |

12 | up to 98 | 3 |

fourteen | 98. 104 | 3. 5 |

14, 16 | 104. 110 | 4. 5 |

16, 18 | 110. 116 | 5. 6 |

twenty | 116. 128 | 6. 8 |

24 | up to 164 | over 8 |

Wheel sizes for kids ‘bikes are separate from adults: kids’ range ends on 24 “wheels, while for adults it just starts (excluding 20” BMX). 24-inch wheels can be safely attributed to teenage and universal (for small adults). Of course, this data will only help you choose a bike, otherwise you need to try it on.

## What does the wheel consist of?

First of all, it is worth learning about the structure 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.
- Knitting needles. Together with the rim, they take up most of the load when driving. Depending on the size of the wheel and its type, there can be a different number of spokes, in addition, they can be intertwined in several ways. There are special holes on each rim for attaching these devices. Since the rear wheel of a bicycle always has a heavy load, until the 80s. XX century. it always had a larger number of spokes. 40 (and 32 on the front). However, most modern bicycles have an equal number of spokes on both wheels. Depending on their size, their number ranges from 24-36 pieces. So, for example, on one of the most common sizes of a bicycle wheel rim (26). 32 spokes.
- Tires and tubes. Most models have both, but many mountain bikes use specialized tubeless tires. Air is retained in them due to their tight fixation on the wheel rim.
- In addition to all of the above, plastic reflectors. reflectors are attached to the part of the bike under consideration. Their type and number usually depends on the wishes of the vehicle owner.

1Place your bike upright against a wall or on a stand. http://pad2.whstatic.com/images/thumb/4/4d/Measure-a-Bicycle-Wheel-Step-1-preview.jpg/550px-Measure-a-**Bicycle**-Wheel-Step-1-preview. jpg http://pad2.whstatic.com/images/thumb/4/4d/**Measure**-a-Bicycle-Wheel-Step-1-preview.jpg/300px-**Measure**-a-Bicycle-Wheel-Step-1-preview.jpg http://d5kh2btv85w9n.cloudfront.net/3/3b/Measure a Bicycle Wheel Step 1.360p.mp4

2Measure the distance from the point where the tire touches the ground to the point where the rubber tire enters the metal rim. The resulting distance will be the thickness of the tire. http://pad2.whstatic.com/images/thumb/1/11/**Measure**-a-Bicycle-Wheel-Step-2-preview.jpg/550px-**Measure**-a-Bicycle-Wheel-Step-2-preview. jpg http://pad2.whstatic.com/images/thumb/1/11/**Measure**-a-Bicycle-Wheel-Step-2-preview.jpg/300px-Measure-a-Bicycle-Wheel-Step-2-preview.jpg http://d5kh2btv85w9n.cloudfront.net/1/1a/Measure a Bicycle Wheel Step 2.360p.mp4

3 Multiply this value by 2 as the tire covers the wheel from all sides, top and bottom. http://pad1.whstatic.com/images/thumb/d/da/Measure-a-**Bicycle**-Wheel-Step-3-preview.jpg/550px-Measure-a-Bicycle-Wheel-Step-3-preview. jpg http://pad3.whstatic.com/images/thumb/d/da/Measure-a-Bicycle-Wheel-Step-3-preview.jpg/300px-Measure-a-Bicycle-Wheel-Step-3-preview.jpg http://d5kh2btv85w9n.cloudfront.net/7/76/Measure a Bicycle Wheel Step 3.360p.mp4

4 **Measure** the diameter of the wheel rim. http://pad3.whstatic.com/images/thumb/0/04/Measure-a-Bicycle-Wheel-Step-4-preview.jpg/550px-Measure-a-Bicycle-Wheel-Step-4-preview. jpg http://pad3.whstatic.com/images/thumb/0/04/Measure-a-Bicycle-Wheel-Step-4-preview.jpg/300px-Measure-a-Bicycle-Wheel-Step-4-preview.jpg http://d5kh2btv85w9n.cloudfront.net/c/ca/Measure a Bicycle Wheel Step 4.360p.mp4

5Add the rim **diameter** to the thickness of the tire you multiplied by 2. This adds up to the wheel size. http://pad2.whstatic.com/images/thumb/c/c4/Measure-a-Bicycle-Wheel-Step-5-preview.jpg/550px-Measure-a-Bicycle-Wheel-Step-5-preview. jpg http://pad2.whstatic.com/images/thumb/c/c4/Measure-a-Bicycle-Wheel-Step-5-preview.jpg/300px-Measure-a-Bicycle-Wheel-Step-5-preview.jpg http://d5kh2btv85w9n.cloudfront.net/1/12/Measure a Bicycle Wheel Step 5.360p.mp4

## Sizes of bicycles and tires

We measured the rim, how to find out the diameter of a bicycle wheel. we found out, you can get acquainted with the standard sizes of your tires, as well as find out what type of bike they are mounted on.

Choose the size of the rubber for your two-wheeled friend, not for beauty and personal sympathy, but based on the environment and road surface.

- On small pieces, for example, for children, folding, BMX. wheels with a radius of 20 inches and a rim of 406 mm are installed.
- For teenagers and folding bicycles for adults, a “shoe” with a radius of 24 inches and a rim of 507 mm is recommended.
- Mountain models are equipped with rubber with a diameter of 26
**inches**and a rim of 559 mm. These tires feature an aggressive tread pattern to aid traction in off-road conditions. - If you are a fan of city cycling, as well as participating in races and competitions, then most likely you are the owner of either a road or road two-wheeled partner. Your manufacturer has supplied you with a 28 ” rubber with a rim circumference of 622 mm.
- Finally, the owners of mountain 29ers “put on” the largest tires with a diameter of 29
**inches**and a circumference of 622.

A few words about the exact size when buying a new rubber, you should know the rim rim diameter. You will need it when buying new wheels.

## Correct ratio of bike frame to height

Before we look at the most common bicycle wheel sizes, you should know that the total diameter of a bicycle wheel depends on the rim diameter and the thickness of the bicycle tire.

### How to Measure Bicycle Wheel Circumference For A Cycling Computer

A proper bicycle wheel consists of a rim, spokes, hub, and a tire with a tube. In some modern models, individual components are missing or combined.

**Bicycle** wheels have their own parameters, which often serve to determine the type of this vehicle. For example, wide 26 “wheels are found on mountain bikes, while 700 mm (28”) wheels are often found on a road or road bike. The diameter and width of the wheels affect the speed characteristics and cross-country ability of the **bicycle**: the larger the diameter and narrower the **wheel** rim, the faster the bike will go, and the bike with wide and small wheels will not be able to move fast.

Of great importance in the design of a bicycle wheel are the spokes, which are designed to give the wheel strength and elasticity. Most modern wheels have 32 spokes in their set. Wheels with an increased number of spokes are used for bicycles with increased reliability without weight restrictions.

Most often, the diameter of the bicycle wheels is indicated in English inches. There are currently seven of the most common bicycle wheel sizes: 20, 24, 26, 27, 27.5, 28 and 29 inches (although these are rough estimates). So:

20 inch wheels (rim diameter 406 mm). BMX bikes, folding bikes and kids bikes.

24 inch wheels (rim diameter 507 mm). teenage bicycles, bicycles for freeriding and similar extreme disciplines, old Soviet bicycles such as Altair and Salut.

26 inch wheels (rim diameter 559 mm). mountain bikes, city bicycles and walking bikes. Most common wheel size.

27 inch wheels (rim diameter 622 mm). road bikes.

27.5 inch wheels (rim diameter 584 mm). mountain bikes. The wheel diameter of 27.5 inches is an intermediate option between 26 and 29 inch wheels on mountain bikes. Bicycles with such wheels appeared on the market in 2013.

28 inch wheels (rim diameter 622 mm). hybrid and road bicycles, old Soviet bicycles such as “Ukraine” and “Aist”.

### Bicycle Parts. **wheel** and tires size

29-inch wheels (rim diameter 622 mm) are a relatively new standard for mountain bike wheel dimensions and are rapidly gaining popularity in the market. A bicycle equipped with 29 inch wheels is called a Twentiner or simply Niner.

As you can see, wheels with a **diameter** of 27, 28 and 29 inches have rims of the same diameter. 622 millimeters. The difference in wheel size is due only to the thickness of the tires.