There are many reasons for which people buy a bike. Regardless of the purpose of this, the means of movement is the most important element are tires that are often changed. What are they and how to choose them correctly, you can learn from this article.
Standard tire parameters
The size of the wheels (rim) is a decisive factor, because they depends on what purpose a bike is suitable. Previously, during the selection of cycle bumps, they were focused only on the external size of the circle, but over time, a rather large number of manufacturers appeared in the world, as a result of which confusion arose. In order to be easier to navigate in the types of tires and properly select them for their bike, was developed Unified system of standards.
It was developed by the International ISO standardization organization, known earlier as Etro. According to this system, the width of the tire, internal and outer diameters of the rim and height is taken into account.
These parameters are directly dependent on the year of release, the manufacturer and, of course, the destination of the bike.
Children's bicycles, hunters, scooters and some folding structures have, as a rule, the external diameter of the rim from 12 to 24 inches. In models for adults, this parameter is within 26-28 inches.
The inner diameter of the rim, or, as it is also called, the landing diameter is the most important parameter at the tire, since it should coincide with the inner width of the bike rim.
Internal tire size, according to ISO standards, closely connected not only with an external diameter, but also with a width. It, depending on the purpose of the tire, can fluctuate in the range of 18-75 mm.
There is a table in which the tire parameters are specified in accordance with the produced bicycle models and their destination.
For two-wheeled vehicles produced in France and in some other European countries, there is a table of conformity in which the designations of internal and external diameters, widths and heights have a slightly different kind.
What does marking mean?
Marking on the tires is almost always on the side.
Most often, dimensions indicate millimeters. Marking in the form of two numbers, such as 35-559, or 37-630, denotes the width and inner diameter (landing rim) of the tire. The first number is the width, and the second - diameter.
Sometimes the marking has a slightly different kind, and the numbers are indicated in it not only in millimeters, but also in inches. For example, such a combination of numbers as 622x19, indicates the inner diameter in millimeters and the external size of the part in inches.
Tires can also be marked by numbers only in inches. The view 24x1 indicates that the number 24 is an external diameter, and a strange one at first glance a combination of numbers 1 and? Indicates the width of the tire. Sometimes instead of an integer and fraction, the width indicates in the form of a non-target number with a point, for example, 26x1.75.
Often there is a marking of three numbers: 20x1.75x2 or 28x1 ⅝x1. In this case, the first number is the outer diameter, the second is the height, but the third is the width.
For bicycles produced in France or some other European countries, a different marking has been adopted. The type of 650A means that the outer diameter of the tire is 650 millimeters, the letter A is its width. But such marking is currently being found more and less often, a more accurate designation of diameter and width came to replace it. Today it is customary to label cycling tires as follows: 650-38C, where the first number is an outer diameter, the number that stands after hyphena denotes the width of the tire, and the letter (in this case it is C) is the size indicating its inner diameter.
Measuring wheel diameter
In order to find out the wheel diameter, it is necessary to measure its radius using a roulette. To measure the bike is installed on a flat surface and, having put forward a flexible tool tape into several centimeters, lowered its lower edge to the ground or floor, pre-placing the elongated part as close to the sleeve axis.
To find out the full diameter of the wheel in millimeters, you need to multiply the result by 10, and then 2.
You can determine the diameter of the wheel and without roulette. For this you need Apply the coloring composition in the form of a bracket and turn the wheel to one turn. The length of the line from 1 point to the second is divided by π (3.14) and, if necessary, translated in inches, separating the result obtained by 2.54.
How to choose?
In order to choose a new tire correctly, you must navigate, of course, on the marking and compare the data with the notation specified on the old bus. The compatibility of the parameters must be maximum. But, as practice shows, comparing first of all the width of the tire with the inner width width.
From the ratio of these two magnitudes, two very important parameter for the cyclist are dependent: Ranat and clutch. Wide relative to the inner size of the rim Tire allows you to better control the bike on the turns, the clutch with the surface of such a tire is better. But unfortunately, The bike with such width is worse.
The optimal ratio between the width of the tire and the inner size of the rim is 1: 1.5 or 1: 2, and all the values lying from 1.5 to 2.
For a highway bike with a rim width of 13 mm, tires from 18 to 25 mm are in width, and in the case of 15 mm it is better to stop its selection on a tire with a marking of 23-32 mm.
For light cross-country models with a rim width of 17 mm, 25-37 mm tires are needed into width, and instances with a width of 28-44 mm are suitable for heavy crosses with a rim.
Models intended for mining cycling, with a rim of 19 mm, a tires are suitable width of at least 28-60 mm. For bicycles used in cycling and easy extreme, in which the size of the rim is 20 mm, produce tires width from 28 to 47 mm. And with the rim width in 21 mm, the width of the tire will be within 35-50 mm.
The bicycle used in extreme sports, with a rim at 23 mm, the width of the tires should be within 40-50 mm, the width of 44 to 57 mm is suitable for the rim in 25 mm, and for the largest rim in 32 mm, the bus width is not less than 75 mm.
It must be remembered that Too narrow tire greatly increases the risk of puncture and damage to the rim.
Too wide tire will reduce the handling at low speed, even if it is slightly dropped. When the turn is overly a wide tire can lead to a breakdown from rim. Besides, Wearing of such tires occurs much faster than the correctly selected option.
Affects the choice of width of the tires. The presence of spikes. Too wide studded tires together with a narrow rim - not the best combination for a good clutch with the surface, since when turning the spikes located in the side part, they will practically not touch the surface.
The inverse situation will be folded with a narrow tire and a wide rim.
When performing the rotation of the spikes completely in contact with the surface, but the insufficient width and bias will lead to the fact that the bike will go on the right or left, depending on the rotation, board.
What are the sizes of bicycle tires, see the next video.