Advice 1: How to read tire sizes

The inscription on the side of any tire are full of information about the tire. Knowing how to decipher these inscriptions, it is possible to obtain all the characteristics of rubber and find out whether it is suitable to a certain type of car or type of disc. There are metric how to specify tyre size and the so-called English.
How to read tire sizes
Carefully inspect the sidewall of the tyre. Look for her label of species 165/70R13 (tire VAZ-2106). Figures may vary depending on the dimension of rubber, but, as a rule, the label has just such an idea. The first digit (165) indicates the section width in millimeters. The second number (70), third the stroke / indicates the height of the profile as a percentage of its width (the first digit). The letter R signifies the type of tyre (radial). The next number after the letter R shows the diameter of the tyre in inches. 1 inch = 25.4 mm. rim diameter tyres shall be equal to the diameter of the disk.
The designation of cross-ply tires, which had widespread until the early 80-ies of the last century, has the form 8,10-15. The first digit represents the section width in inches, and the second is the diameter of the tire, also in inches. The height of the profile not specified, but most often is equal to 80% of its width. In addition, occasionally found the same designation, expressed in millimeters. For example, 205-380. The numbers are rounded to the nearest five or zero.
The English system the dimensions of the tires most often found on tires designed for tuning SUV, ATV tire, truck terrain. Has the form 25х8-12 (tire for ATV). The first digit represents the overall diameter of the mounted and inflated to recommended tyre pressure. The second number that comes always after the cross, means the total width of the profile. The third is the diameter, which should be equal to the diameter of the disk. In the domestic truck ATV size tire are also described, but instead used inches millimeters. Occasionally found other references of this size, for example 25х8R12. Numbers their meaning thus preserve.
Before the digital designation tire size can include the letters P or LT. The letter P indicates that the tire is intended for passenger cars, the letter LT for light trucks. In the United States for light trucks include SUVs, pickups and vans. Letter, size after standing at some distance indicates the speed index of the tyre, i.e. the maximum speed at which it is designed. In addition, radial tyres with metric designation dimensions often the speed is indicated before the letter R.

Advice 2 : How to decipher the markings Bicycle tires

For marking of Bicycle tyres, there are certain standards. With the exception of Britain and France, which use their own systems. Labeling gives information about the width and internal diameter of the tyre, sometimes about altitude.
How to decipher the markings Bicycle tires

The diversity and mutual inconsistency of marking systems sunglasses

The standard classification of Bicycle tires was developed by the International organization of standardization. She is known by the acronym ETRO - European technical organization rims and caps. Only in Britain and France this system is not adopted. In the marking are given width women's shoes and its inner diameter in mm. It is necessary to know to select the size of the rim. Often the parameters are specified in inches, but such marking is not precise enough. You can consider the marks in detail.

Understanding labeling bike tires is complicated by the fact that one and the same size tire can be in different countries are marked in different ways. So often the same encoding does not mean identical size. The confusion began in the mid-twentieth century at times equally marked tyre suitable on the same rim. As a result, the rim 26 size fit tyre width of 25mm, and the actual outer diameter of the wheel was equal to 24 7/8’. Also in the 70s was marked, deliberate dishonesty of the manufacturer to specify the parameters of the tyre, to gain advantage in the competition.

Traditional marking and European standard

Traditional is the marking of the two numbers. The first one is the value of the outside diameter of the tire. For example, a 26’ or 700 mm, depending on the accounting system. The second number is the width of the tyre. In France, this use of the letter code, where A is the most narrow tire, D is the widest. Thus, the marking on velasina looks so: 26×1.75, 27×1 1/4, 650B. You can see that the width can be indicated as a decimal or simple fraction. It is necessary to clarify that it is not interchangeable notation despite the mathematical equality. It tires of different sizes.

Unlike traditional systems, a common standard ETRO acknowledges specifying parameters only bike. the result is a three-digit number. Can result according ETRO and traditional systems with simple fractions: 622 = 28x1¾, 635 = 28x1½, 622 = 28x1½, 630 = 27x..., 622 = 27×1 ¼ , 571 = 26×1, 597 = 26×1 ¼, 590 = 26× ¼ 1, 584 = 26×1½", 571 = 26×1 ¾ , 520 = 24×1, 547 = 24×1 ¼, 533 = 24×1 ½ , 540 = 24×1 3/8, 445 = 20×1 ¼, 406 = 20×1¾, 419 = 20×1¾, 205 = 12 ½ ×2¼. Complying with ETRO, and a traditional system with decimal fractions: 559 = 26×1.00 to 2.3, 599 = 26×1.375, 507 = 24×1.5 to 24×2.125, 406 = 20×1.5 — 20×2.125.
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