Finding the right summer tyres for your car is not that difficult. Behind the frightening intricacies of alphanumeric tyre designations are quite explainable parameters, which you need to focus on when choosing tyres. The most important of these is the size.

Size

Tyres for a car are selected according to the size grid, like shoes for a person, in accordance with the size of the feet. Unsuitable tyres for the car will cause a lot of problems – from the banal fender liner erasure in the wheel arches and ending with the decrease in controllability or off-design loads on the chassis of the vehicle. Ideally, the tyre size should be the same as it is indicated in the car manual. Can there be exceptions to this rule? Yes. Many car manufacturers allow the use of alternative tyre sizes and a different rim size grid. How much difference in tyre size is acceptable? You can find approvals for suitable sizes in the technical documentation or on a sticker, which is often located on the inside of the glove compartment cover, on the side of the car in the doorway, on the inside of the fuel tank hatch, on the end of the open driver's door.

Some car owners experiment with tyre sizes at their own risk. For example, they install low-profile tyres on the wheels, thereby emphasizing the appearance of the car. Others put tyres with a high profile height to improve ride comfort. Installing tyres that are not the right size can result in increased fuel consumption, poor controllability, and excessive noise. In addition, the car's speedometer and odometer will display incorrect data: their values decrease when using larger tyres and increase if the size is smaller than the factory one.

Our advice to you is to stay within approvals and common sense. If you already decide to put the tyres at your discretion, then select the size one step more or less than the standard one.

Basic information on a particular model is encrypted in the inscriptions on the sidewall of the tyre.

So, what is hidden behind the tyre size designation. Take, for example, the most popular passenger car size 205/55 R16 91V :

  • 205 is the width of the tyre profile in millimeters. There is little disagreement in determining the width parameter, since some manufacturers measure it between the protruding outer points of the sidewalls, while others measure it by the contact patch of a fully inflated tyre with the roadway. However, the measurement errors in both cases are small. But do not be surprised if, in practice, tyres with the same designation from different manufacturers will vary slightly in width.
  • 55 is the aspect ratio of the height of the tyre profile to its width. It is important that the height is measured in percentages, not in millimeters. For the example in question, the profile height in the metric system is 205 ⋅ 0.55 = 112.75 (mm).
  • R – type of tyre design (many confuse this designation with radius). The letter of the Latin alphabet R stands for radial design. Other types are almost non-existent in the modern tyre industry.
  • 16 – and this is also not a radius, but the inner size of the tyre in inches (the rim diameter, in other words). The indicator determines the possibility of installing a tyre on a rim of a specific size.
  • 91 is the tabular value of the load rating. The parameter characterizes the maximum load that the tyre can withstand when moving at the maximum allowable speed.
  • V – the speed rating, which determines the maximum allowable tyre operating speed.

You can read more about tyres size comparison, and all the markings of tyre products in the article "Tyres marking from A to Z". Load and speed ratings play an important role in the selection of summer tyres. Therefore, it is desirable to take a closer look at their analysis.

Popular summer tyres

Load and speed ratings

The load rating determines the car load capacity. It describes the maximum load in kilograms for the indicated maximum permissible speed while maintaining the correct tyre pressure. Decryptions of load ratings are given in the special tables. You can also calculate the required rating yourself: for summer tyres, it is enough to divide the curb weight of the car by 4 and multiply the result by 1.2.

The tyre load rating must not be less than the factory value. And if it's bigger, it's even better. The reserve allows the tyre to withstand excessive loads and makes it less vulnerable to the formation of "bumps" when driving on bad roads.

Special requirements regarding the ability to withstand increased loads are made to tyres for crossovers and SUVs. Cars of these classes have a high center of gravity and have a greater mass in comparison with passenger cars. In addition to high load ratings, such tyres usually have a reinforced cord and sidewall design in order to maintain a constant contact patch and not be damaged under heavy loads. In the size designation, reinforced models are often labeled XL, Reinf, Reinforced or RF.

Deciphering the load and speed ratings in the labeling of tyre products.

The speed rating of tyres is indicated by the letters of the Latin alphabet. Its decoding is given in the table above. Behind each letter is the maximum permissible speed for safe movement in a car, at which the performance specifications of tyres are maintained, laid down by the manufacturer. The further the letter down the alphabet, the faster the tyre is. If you are a fan of speed and know where you can speed up safely for yourself and others, feel free to take tyres with a larger speed rating.

Tyre pressure

An important aspect of the proper operation of tyres is maintaining the required pressure in them. How many atmospheres it is necessary to pump up the wheels is indicated on the sticker mentioned above with an acceptable size grid of tyres suitable for the car. Recall that it can be found on the back of the glove compartment cover, on the rack in the doorway, in the fuel tank hatch, at the end of the open driver's door.

Pressure value depends on the size of the tyre, the load level of the car, and the speed limit. Usually, all these options are indicated on the sticker. So, when traveling with the whole family on a long journey with a lot of luggage, it is advisable to pump up a 205/55 R16 tyre from 2.1 atm to 2.4 atm (the numbers are taken arbitrarily and are not the ultimate truth, for different cars they may differ).

To inflate the wheels and maintain the correct pressure in the tyres, it is enough to get an autocompressor.

If the tyre is over-inflated, it becomes noticeably harder, loses proper traction, increases braking distance, and may be vulnerable to damage when hitting rocks or road potholes. And if the pressure is below normal, there are difficulties in driving the car, the tyre roll increases when cornering, the level of fuel consumption increases, and the tread wears out faster. You can control the pressure in the tyres and pump up the wheels using a pump with a pressure gauge.

Date of manufacture

The date of manufacture of the tyre is indicated by a four-digit number on the sidewall (often inside an oval stamp). The first two digits are the serial number of the week, the last two digits are the year of manufacture of the tyre. For example, the number "0720" stands for the 7th week of 2020.

The date of release of the tyre from the conveyor is indicated by a four-digit number: the first two digits are the serial number of the week, the last two are the year of production.

New tyres that have been properly stored and not dried out will perform better on the road than stale tyres. Failure to comply with the storage rules will cause a loss of elasticity and the appearance of microcracks. These signs of aging degrade tyre performance. It is preferable to buy new summer tyres, released no more than a year ago. Tyres can be stored for up to 3 years, but it is very difficult to check the conditions for their proper preservation. This remains on the conscience of the tyre seller and it must be clarified before buying.

Popular summer tyres with non-directional symmetric tread pattern

Tread pattern

The summer tyres segment is dominated by an asymmetric design of a tread pattern. Protectors of a similar structure have equally stable driving qualities both when driving on hot dry asphalt and when conquering water obstacles in rainy weather. The inner zone of the asymmetric tread is usually responsible for "wet" grip and the rapid removal of water from the contact patch, while the outer part ensures the car's stability when maneuvering. Note that tyres with such a tread pattern must be correctly put on according to the Inside and Outside marks.

The non-directional symmetric tread pattern has an average driving parameters. Installing tyres with it does not depend on the direction of rotation of the wheel. This versatility allows user to easily perform scheduled wheel changes to maintain even tread wear. Tyres with such pattern are well suited for the rhythm of city driving. Their strengths are comfort and durability, their weaknesses are relatively low resistance to aquaplaning and reduced maneuverability at high speeds.

The directional symmetric pattern is aimed at quick self-cleaning of the tread from water when driving on a wet roadway. It provides stability of control and driving stability of the car during rainfall. However, summer tyres with a characteristic herringbone pattern are the noisiest. They are chosen for safe high-speed driving, when comfort is secondary. Rubber with a directional symmetric tread is placed on the wheels, taking into account the direction of the car. The wheel rotation vector is indicated by an arrow labeled Rotation on the sidewall of the tyre.

A visual difference between different types of tread pattern in summer car tyres:
on the left – non-directional asymmetric; in the center – directional symmetric; on the right – non-directional symmetric.

Symmetric tread pattern is often found in the all-season tyres segment. Formally, all-season tyres wear out faster, do not tolerate frost and intense heat, and are several times inferior in terms of driving properties to specialized winter and summer tyres. It is very difficult to combine opposed characteristics in one tyre, therefore, such tyres can only be recommended for regions with mild winter and moderate summer climates without scorching heat.

Directional symmetric summer tyres

Noise, durability, wet grip, fuel efficiency

Noise, wear resistance, wet grip and fuel efficiency ratings are more of a marketing ploy and semi-sales test results. However, all other things being equal, these parameters can be taken into account.

Quiet tyres with a low noise level give acoustic comfort on the road. This indicator directly depends on the tread pattern and tyre wear rating. The higher the Treadwear value, the longer the tyre will last. But the tyre will be stiffer and, as a result, noisier. Low-cost summer tyres from Chinese tyre manufacturers very noisy as well.

The wet grip rating of a tyre is usually denoted by letters of the Latin alphabet from A (best grip) to E (worst grip). The parameter is important for those who often have to drive in wet weather: the higher the grip rating, the better the tyre “holds” the road and the safer the ride. The fuel consumption rating is marked in the same way. This figure includes the tyre's rolling resistance. Less resistance promises savings in petrol consumption, and vice versa – a high rolling resistance rating increases fuel consumption.

Interesting fact. Lately, the so-called "green" tyres, manufactured with care for the environment, are gaining popularity. Eco-friendly tyre contains natural and recyclable raw materials in its composition, it is assigned high fuel efficiency ratings. Eco tyres contribute to the protection of the environment by reducing fuel consumption, which minimizes the amount of harmful emissions into the atmosphere. Also, efficient tyres are often installed on the wheels of electric vehicles from the factory.
Low noise summer tyres

Puncture proof

To protect the driver from the need to change a punctured tyre with a spare tyre somewhere on the side of the road RunFlat and Seal tyres will help. Tyres of the first type have a particularly reinforced sidewall design and allows user to continue driving for several tens of kilometers with a complete loss of pressure. Visually, such tyres do not sag, which prevents damage to the rim. RunFlat tyres will help you get to the tyre shop without having to take the spare tyre out of the boot. Inexperienced drivers behind the wheel will certainly appreciate such a gift of fate in the event of a wheel puncture.

RunFlat tyres allow to continue driving with punctures for up to several tens of kilometers.

The downside of RunFlat tyres is their heavy weight and stiffness, which reduces ride comfort, as well as the need to use pressure sensors in the wheels.

Different tyre manufacturers call the technology differently. The most common options are listed below:

  • ZP, ZP SR (Zero Pressure) – Michelin ;
  • RFT (Run-Flat Type) – Bridgestone ;
  • SSR (Self Supporting Run-Flat) – Continental ;
  • ROF (RunOnFlat) – Goodyear ;
  • Run Flat – Nokian ;
  • XRP (eXtended Runflat Performance) – Kumho ;
  • DSST (Dunlop Self-Supporting Technology) – Dunlop.

Seal self-sealing tyres offer a different principle of puncture protection. Special sealants are added to the composition of their rubber compound, which tighten small punctures in the tread area and allow driver to continue moving. Tyres produced using this technology are no different in terms of weight and ride comfort from traditional summer tyres. However, they cost more. Self-sealing tyres also do not have a single designation – they are labeled with the designations SelfSeal, SEALGUARD, SealInside, etc.

Seal technology seals small punctures by self-sealing the tread.

Self-sealing technology provides protection only from small punctures – severe tread damage and side cuts are too hard for it.

Brand

The lion's share of the tyre market is controlled by a few reputable companies that produce top tyre brands. Under the name of the original brand, they produce high-quality premium tyres. In particular, these are summer models best tyre brand Continental, Michelin, Pirelli, Bridgestone, Goodyear, Toyo, Hankook, Kumho. The giants of the tyre industry run a huge number of sub-brands. With a less popular name, tyres from the subsidiaries of large corporations are made to the same strict quality requirements, but they are cheaper to purchase. More details about the "Subsidiary brands of leading tyre companies" are described in the material of the same name.

The best developments in the tyre industry are first introduced into practice in the original products of reputable brands. Tyres from their "daughters" often use the developments of a couple of years ago, once used in the top models of past seasons. By the way, buying summer tyres that are not the latest developments can turn into a profitable investment –models from previous years are cheaper and they often have a lot of reviews. In small sizes, the difference between the low-cost segment and the top level of summer tyres is usually small. And if you pay a little more for the brand, you can get high-quality summer tyres with safety without compromise.

Original branded tyres and subsidiaries' products from the giants of the tyre industry can be produced at the same facilities.

A separate story is the tyres come from the China. At first, Chinese tyre manufacturers produced, to put it mildly, very mediocre products. However, years of careful polishing of manufacturing processes have done their job and China's tyre industry has made a notable breakthrough. "Should I buy Chinese tyres?" and “Which Chinese tyres does it make sense to buy?” – read in separate articles.

Euromarking and homologation

Since 2021, the updated European Union regulation on tyre labeling has come into force. Henceforth , stickers with basic information on the model are put on all new tyres. In appearance, they resemble energy label stickers, which can be seen on the body of any new household appliances.

Euromarking stickers contain a QR code with a link to the tyre page in the unified EPREL database, information about the model, brand, size, speed and load ratings of the tyre, manufacturer's code. Also on the euro labels ratings of wet grip, fuel efficiency, noise comfort level, grip on snow and ice are indicated . “Updated Tyre Labeling Rules” is available in the relevant material.

The Eurolabel contains key information about a specific tyre model.

For specific brands and models of cars , homologated tyres have been produced. Such tyres are developed taking into account the advantages of a particular car and the agreement of the automaker. It reveals the potential of powerful power units under the hood of top-end cars. When developing homologated tyres, the technical and design features of the vehicle are taken into account so that the vehicle can adapt to its tasks as much as possible.

Specialized tyres take into account the speed specifications of the car, the dynamics of braking and acceleration, controllability, stability on the road, smoothness and comfort, fuel consumption, noise level, safety, weight and vehicle design. After a series of tests at the test sites, changes are made to the composition of the rubber compound of the tyre and its tread pattern so that the model meets the needs of the automaker as much as possible. Homologated tyres are recommended to be installed only on the wheels of those cars for which the tyres are intended. More information about "What are homologated tyres" is described in the material of the same name.

_____

It is advisable to take care of the search and purchase of summer tyres in advance. Before the onset of mass hype, there are more choices in stores, and prices for tyre products are more pleasant. Good luck on the road!