Product Type
The type of tyre is the type of vehicle for which it is designed.
This parameter is determined mainly by the height of the profile in centimeters, and in some cases by the size and load index. In general, there are three main types of tyres - for
cars and SUVs, for
SUVs and
vans. Here is a more detailed description of each option.
— Passenger car. Tires with a relatively low profile height for a wide range of passenger cars, aimed primarily at smooth roads and more or less favorable operating conditions. Among such products of the tire automobile industry you can find both rubber exclusively for passenger vehicles and tires for SUVs (SUVs, crossovers, city SUVs). SUV tires differ from their traditional passenger counterparts by increased radius and profile height, reinforced internal structure, as well as increased load indices.
— Off-road. SUVs are designed for more difficult conditions than regular cars; they often have to deal with difficult terrain or some high unevenness. Therefore, tires of this type have a significant profile height - more than 14 cm. It is worth considering that such tires can have different specializations - both all-terrain and off-road; For more details, see “Purpose”.
— Minibuses. Tyres designed for relatively heavy vehicles – minibuses and mini trucks. Such vehicles still does not reach the full-fledged f
...reight transport, however, they have more weight than passenger cars. Accordingly, tyres for such vehicles has a high load index.Width
Tire section width is the distance between the sidewalls of an inflated but not loaded tire. As a rule, this parameter is indicated in millimeters, but there are also inch designations for the profile width.
Width is one of the characteristics that determines the compatibility of a tire with a specific wheel (the second characteristic is the mounting size). It is worth noting that the width of the tire does not have to strictly correspond to the width of the rim; certain deviations are allowed. There are special tables that allow you to determine the permissible width values for a particular wheel; in addition, such recommendations may be indicated in the documentation for a specific car.
The following tire width options are available on the modern market:
135 mm,
145 mm,
155 mm,
165 mm,
175 mm,
185 mm,
195 mm,
205 mm,
215 mm(in inches this is
8.5”),
225 mm,
235 mm,
240 mm(in inches this is
9.5”),
245 mm,
255 mm,
265 mm(in inches this is
10.5”),
275 mm,
285 mm,
290 mm(in inches this is
11.5”),
295 mm,
305 mm,
315 mm,
320 mm(in inches this is
12.5”),
325 mm,
335 mm,
345 mm(in inches this is
13.5”) and
over 345 mm(
over 13.5”).
Aspect ratio
Tyre aspect ratio. This parameter is usually expressed as a percentage of the width, since it is not the height itself that is of practical importance, but its ratio with the nominal section width.
In general, the lower the ratio, the more stable the tyre, the better it is suitable for high-speed driving on flat roads. Higher ratio, in turn, work better on rough surfaces and over obstacles, making them good for bad roads and
off-road. If we talk about specific numbers, nowadays, the following options are spread on the market:
— Low profile tyres:
25%,
30%,
35%,
40% ;
— Medium profile :
45%,
50%,
55%,
60% ;
— High profile :
65%,
70%,
75%,
80%,
82%,
85%, and
90% or more.
Load index
The maximum weight load that the tyre is able to carry. It is denoted by a conditional figure, each of which corresponds to a certain value:
66 - 300 kg, 67 - 307 kg, 68 - 315 kg, 69 - 325 kg, 70 - 335 kg, 71 - 345 kg, 72 - 355 kg, 73 - 365 kg, 74 - 375 kg, 75 - 387 kg, 76 - 400 kg, 77 - 412 kg, 78 - 425 kg, 79 - 437 kg, 80 - 450 kg, 81 - 462 kg, 82 - 475 kg, 83 - 487 kg, 84 - 500 kg, 85 - 515 kg, 86 - 530 kg, 87 - 545 kg, 88 - 560 kg, 89 - 580 kg, 90 - 600 kg, 91 - 615 kg, 92 - 630 kg, 93 - 650 kg, 94 - 670 kg, 95 - 690 kg, 96 - 710 kg, 97 - 730 kg, 98 - 750 kg, 99 - 775 kg, 100 - 800 kg, 101 - 825 kg, 102 - 850 kg, 103 - 875 kg, 104 - 900 kg, 105 - 925 kg, 106 - 950 kg, 107 - 975 kg, 108 - 1000 kg, 109 - 1030 kg, 110 - 1060 kg, 111 - 1090 kg, 112 - 1120 kg, 113 - 1150 kg, 114 - 1180 kg, 115 - 1215 kg, 116 - 1250 kg, 117 - 1285 kg, 118 - 1320 kg, 119 - 1360 kg, 120 - 1400 kg, 121 - 1450 kg, 122 - 1500 kg, 123 - 1550 kg, 124 - 1600 kg, 125 - 1650 kg, 126 - 1700 kg, 127 - 1750 kg, 128 - 1800 kg, 129 - 1850 kg, 130 - 1900 kg, 131 - 1950 kg, 133 - 2060 kg.
While choosing according to this indicator, it is worth considering not only the maximum weight of the car for which tyres are going to buy, but also the distribution of weight along the axles. With passenger cars, everything is simple — the weight is distributed approximately equally, so to determine the load on each wheel, it is enough to divide the maximum mass of the car by 4 (the number of wheels). H...owever, in minibuses, light trucks and SUVs, the situation is different: the weight distribution can be unequal, so you should refer to the manufacturer's documents or other special sources to calculate the load on each wheel.
Anyway, the load index must not be exceeded — this creates the danger of an accident. In fact, the wheel load should be at least 10 – 15% below the maximum, this will give an additional guarantee in case of abnormal loads. Also note that in some high-speed tyres, with the speed maximum approaching, the permissible load decreases: for example, for tyres with the V index (see "Speed rating") with speed over 210 km/h, it is recommended to reduce the load by 3% for every next 10 km/h increase in speed, similar recommendations apply to models with indexes W and Y. These details are usually described in the manufacturer's documentation and other special sources.
Speed rating
The speed rating that the tyre corresponds to.
This indicator determines the maximum speed that tyre is allowed to operate. It is designated by the letters of the Latin alphabet, each of which corresponds to a certain speed limit:
F — 80 km/h; G — 90 km/h; J — 100 km/h; K — 110 km/h; L — 120 km/h; M — 130 km/h; N — 140 km/h; P —
150 km/h ; Q —
160 km/h ; R —
170 km/h ; S —
180 km/h ; T —
190 km/h ; U —
200 km/h ; H —
210 km/h ; V —
240 km/h ; W —
270 km/h ; Y —
300 km/h ;
The maximum permitted speed must not be exceeded — this creates the risk of an accident. However, there are other rules associated with choosing a tyre by this factor. So, ideally, the actual driving speed should be at least 10 – 15% lower than the speed rating of the installed tyres — this will give an additional guarantee in case of emergency situations. In addition, in some tyre models, as the speed approaches the maximum, the upper limit of allowable load is reduced; see “Load Index” for details.
Orientation
The shape of the tyre tread pattern:
—
Directional. Pattern with a characteristic V-shape. Among other things, such rubber is considered to be especially effective on wet surfaces — in rain, on snow, with an abundance of melt water, etc.: the pattern provides effective water drainage, reducing the risk of hydroplaning and increasing grip. Also, these tyres are well suited for high-speed sports cars (although, of course, their speed rating and specialization may be different). When installing directional tyres, the direction indicated by the manufacturer must be kept.
—
Symmetric. The pattern without signs of directionality is the same both on the outer and on the inner part of the tread. These tyres are easier to manufacture than directional or asymmetric tyres, and are generally cheaper, while still having good performance on a flat and dry surface. In addition, symmetric tyres are as simple as possible to install, they do not need to follow the direction. However, for hard conditions, particularly wet weather, they are poorly suited. So, typically, such tyres are designed mainly for city cars used on short trips on relatively high-quality roads.
—
Asymmetric. Tyres with a different pattern inside and outside the tread. Each of these parts plays a role: the inner part provides water evacuation and reduces the risk of aquaplaning, while the ou
...ter part provides the necessary rigidity for manoeuvrability and stability. While installing, you need to take into account the location of the outer and inner sides, they usually have the appropriate marking. Asymmetric tyres are considered the most advanced, although, of course, the actual characteristics and cost of such products may vary, depending on the brand and the general level. Such tyres are designed mainly for cars of medium and top levels; they are often supplied as factory equipment for advanced cars.Studs ready
A variety of tyres (usually winter tyres) that are not equipped with studs, but have slots for their installation. The meaning of this decision is that, firstly, such tyres are typically cheaper than similar models with pre-installed factory studding, and secondly, the owner is given certain freedom of choice — to stud or not to stud the tyre. In fact, it should be noticed that tyres created
for a stud are initially designed for operation with studs, respectively, without them, they will behave worse than ordinary non-studded ones. In addition, studs made after purchase take hold much worse than factory ones — with more or less intensive use, studs tend to fall out, especially if the tyre does not stud right away, but after some run.
Studded
Winter tyres (see “Season”), supplemented with studs — metal pins built into the tread. Studs improve traction on ice and packed snow: “biting” into such a surface, they do not allow the tyre to slide. On the other hand, on hard surfaces and in loose snow,
studded tyres are noticeably inferior in efficiency to a
non-studded ones.
Fuel efficiency
The rolling resistance rating that the tyre corresponds to. The higher this figure, the lower the resistance, the less fuel is spent to overcome it and the more economical the tyre is. Efficiency indices are denoted by letters of the Latin alphabet in descending order of efficiency:
A(highest efficiency),
B,
C,
D,
E,
F,
G(lowest efficiency).
With other things being equal, more economical tyres tend to cost more, but the difference is offset by fuel economy.
