Summer, winter, 16s, 17s… Almost everyone knows at least the basic characteristics of a car tyre. However, we can read a whole range of details from the marking of the shoes, some of which you may not even have had an idea about.
The tire marking can be found on its outside, so it is easy to read on any car. As an example, let’s take a tire with a label 225/45 R17 91H. What does such marking tell us? Let’s go step by step:
- 225 = width 225 millimeters
- 45 = ratio of height to width, in our case 45% of 225 mm
- R17 = diameter 17 inches
- 91H = weight and speed index, i.e. the highest tire properties
Tire mass index
The mass index number is not directly related to the load capacity, so to get a specific value, it is best to look at the clear table. Our tire has a weight index of 91, which means that one tire can carry up to 615 kg. All mass indices can be found below:
| Mass index | kg / 1 ks pneu | Mass index | kg / 1 ks pneu |
|---|---|---|---|
| 75 | 387 kg | 100 | 800 kg |
| 76 | 400 kg | 101 | 825 kg |
| 77 | 412 kg | 102 | 850 kg |
| 78 | 425 kg | 103 | 875 kg |
| 79 | 437 kg | 104 | 900 kg |
| 80 | 450 kg | 105 | 925 kg |
| 81 | 462 kg | 106 | 950 kg |
| 82 | 475 kg | 107 | 975 kg |
| 83 | 487 kg | 108 | 1000 kg |
| 84 | 500 kg | 109 | 1030 kg |
| 85 | 515 kg | 110 | 1060 kg |
| 86 | 530 kg | 111 | 1090 kg |
| 87 | 545 kg | 112 | 1120 kg |
| 88 | 560 kg | 113 | 1150 kg |
| 89 | 580 kg | 114 | 1180 kg |
| 90 | 600 kg | 115 | 1215 kg |
| 91 | 615 kg | 116 | 1250 kg |
| 92 | 630 kg | 117 | 1285 kg |
| 93 | 650 kg | 118 | 1320 kg |
| 94 | 670 kg | 119 | 1360 kg |
| 95 | 690 kg | 120 | 1400 kg |
| 96 | 710 kg | 121 | 1450 kg |
| 97 | 730 kg | 122 | 1500 kg |
| 98 | 750 kg | 123 | 1550 kg |
| 99 | 775 kg | 124 | 1600 kg |
Tire speed index
The same applies to the speed index of the tire, which is symbolized by a letter, a letter and a number or two letters. The speed index indicates the maximum possible speed from 5 to 300+ km/h. If the sample tire above has an H index, it means a maximum speed of up to 210 km/h. The speed index table will tell you more:
| Speed index | Max. speed | Speed index | Max. speed |
|---|---|---|---|
| A1 | 5 | L | 120 |
| A2 | 10 | M | 130 |
| A3 | 15 | N | 140 |
| A4 | 20 | P | 150 |
| A5 | 25 | Q | 160 |
| A6 | 30 | R | 170 |
| A7 | 35 | S | 180 |
| A8 | 40 | T | 190 |
| B | 50 | U | 200 |
| C | 60 | H | 210 |
| D | 65 | VR | >210 |
| E | 70 | V | 240 |
| F | 80 | W | 270 |
| G | 90 | Y | 300 |
| J | 100 | ZR | >300 |
| K | 110 | – | – |
Special tire markings
Other tire brands include, in addition to the traditional ones winter tire flakes for example letters XL denoting reinforced construction, they are usually tires suitable for SUVs, off-road vehicles, but also pick-ups and vans. Mark FR means rim protection, letters SSR, RFT and others similar can mark tires run-flat.
Then you can still find marks on the tires indicating that it is a specific tire developed according to the requirements of the car manufacturer. For example, BMW tires have an asterisk, Audi a letter A or A0tires for Bentley cars have B in the wheel, the tires for the Porsche 911 have letters THAT and so on. Sometimes, however, you will also come across specially designed tires from “mass” brands, especially their stronger models, or cars that have a higher towing capacity.
Photo: Porsche
Tires for the Porsche 922 model bear the designation “NA”, which has the following meaning: N – approved by Porsche, A – developed for the Porsche 992 model. “Enka” differ from other tires mainly with regard to the geometry, the rubber compound used and the testing procedure .
Tire efficiency marking
In May 2021, there was a change in labeling of tires. The new labels, which we must find on the shoes, now carry more information. European officials hope that drivers will be better informed and, as a result, will save costs and the environment.
On the new labels the structure of listing the rolling resistance classes has changed a braking efficiency on wet roadswhile the noise level is indicated as a number of decibels and at the same time on the scale with the letters A, B or C. In addition, after reading the QR code, customers gain access from the label to additional information about a specific tire in the online EPREL database (European Product Registry for Energy Labeling = European product database with an energy label).
Photo: Continental Barum
This is how the shape of the label changed in May 2021…
Another change concerned light commercial vehicles (categories C1 and C2). For footwear for cars and vans class D is no longer unusedas it was before, but tires that belonged to class E will be moved to it. Tires with properties at the level of classes F and G have been moved to class E in the new labeling. At the same time, the have limited the maximum permitted values of rolling resistance a braking distances on wet surfaces.
The new label also reduced the number of values on the alphabetic and color-coded scale from seven to five. Classes A to C remained unchanged. C1 tires intended for passenger cars, or C2 intended for vans, which were previously in class E for rolling resistance and wet grip, are now classified in class D, which was not used in practice. Tires previously belonging to classes F and G are now classified in class E. The label was supposed to become clearer and easier to understand for consumers.
Photo: Continental Barum
… and thus the individual values. On the new ones, instead of seven (AG), we can now find only five (AE).
And why all this? According to EU representatives, the new label is intended to help consumers it is easier to choose shoes with higher fuel economy and at the same time provide him information on stopping distances. Choosing tires with lower rolling resistance can lead to lower consumption and lower emissions. Information on noise while driving is intended to help reduce noise levels caused by road traffic.
