Information about tyres
Tyres appear quite similar to the eye, but take a closer look at a tyre and you will soon see evidence of the rapid development in technology and design that characterises today's tyres. The modern tyre designs offered today provide much better driving comfort than the tyres that were on the market ten, five, or even just one year ago.
Today's highly advanced tyres are composed of up to 200 different raw materials. Recently, even the design of the tyres has become of importance to consumers. Manufacturers of tyres are doing their utmost to introduce new summer and winter tyres of the best design in terms of appearance and quality.
Radial and diagonal tyres
Today's tyre market consists mostly of radial tyres. The radial tyre was introduced to the market in 1946, and it became a success; previously what was termed diagonal tyres were used. The difference between radial tyres and diagonal tyres is the placement of fabric cords in the tyre's rolling direction. In diagonal tyres, these were placed diagonally relative to the rolling direction of the tyres while in radial tyres the cords are positioned radially relative to the rolling direction. This transition was a vast improvement in tyre properties and nowadays radial tyres are virtually the only tyres being sold.
Although tyres differ in characteristics, basically they have more or less the same structure:
Body of fabric cords. This usually comprises one or two layers, or plies, and they are held together by several rubber coatings.
Belts are layers of steel wires or fabric that increase the stability of the tyre.
The bead, which consists of bundles of steel wires and acts as a seal between the tyre and the rim.
The tread consists of a combination of synthetic and natural rubbers. The rubber in tyres, along with the tread pattern on each tyre provides good properties for how the tyre is used. This may involve for example directional stability, water drainage and braking ability.
The pattern on a tyre is crucial for the specific properties of the tyre. Among other things, the tread affects the grip to the road surface, durability, driving ability and water drainage. It also affects driving comfort, noise level and fuel consumption. Tread patterns can be divided into four categories:
These tyres have the same overall properties no matter how you mount them.
The tread of an asymmetric tyre is divided into two or more parts, so that a special shoulder should be facing outward and the other inward. Tyres that are asymmetric are marked with an inside and an outside.
Fixed-direction tread patterns
On a tyre with a fixed direction tread pattern the parts of the tread point in the direction of rotation for better water drainage at high speeds. These tyres are marked with arrows indicating the direction of rotation.
Some tyres are both asymmetrical and directional. In this case you have left-side and right-side tyres.
Longitudinal tread patterns
The longitudinal patterns, the grooves in the tyre, affect the directional stability of the tyre and its ability to drain water. They also impact the noise level.
Transverse tread pattern
Transverse or non-directional tread patterns affect driving and braking performance. Tyres with this type of pattern drain water better, but cost a bit more.
Sipes are small slots on the tread blocks of a tyre. They have a positive effect on driving and braking performance, but are negative for stability. Well placed sipes improve durability and the noise level of the tyre.
Markings on the tyre
Manufacturer and product names
Tyre size. Example: 195/65 R15. The first number, 195, represents the width of the widest part of the tyre in millimetres. The second number, 65, represents the height of the tyre specified as a percentage of the width. The next number, 15, is the rim diameter and the R in the size designation stands for Radial.
Speed Designation. This is the recommended maximum speed for the tyre in question.
Load index. This number indicates the maximum load that the tyre can withstand.
Serial number and date indication. Example: 3502. The tyre is manufactured in week 35 of the year 2002.
M&S stands for Mud & Snow. A tyre with this marking is developed for winter conditions. These tyres are not always approved as winter tyres when they are marked with M&S, so you should double check. XL, EL stands for Extra Load and indicates that the tyre in question can handle higher loads with higher tyre pressure.
Load and speed index
The load and speed index of the tyre are given together with the dimension specifications. Click on load index and speed index for information on what the indexes on your tyres mean.
195/65 R15 91H
Such a marking on tyre shows, in addition to the width, height and rim diameter also the maximum weight the tyre can withstand. It is in this case the numeral 91 that indicates the maximum weight. The letter H that follows indicates the maximum driving speed to which the tyre can be subjected. What these markings mean exactly can be found in more detail in our guide on speed index and load index.
Change tyres in time for winter!
A winter tyre can be studded, or can be a stud-free, a so called friction tyre. The winter tyres on your car should be marked with M+S, M.S, M&S, M-S, MS or Mud and Snow – these or all similar varieties of a marking and mean the same.
Some tyres on the market are marked with M and S without being tyres specifically designed for winter use, for example, heavy-treaded SUV tyres for jeeps or 4x4 vehicles. You are not permitted to have both studded and non-studded tyres on the same vehicle during winter road conditions.
Tread depth on winter tyres
During the period in which winter tyres are necessary the tread on the tyres should be at least 0.11”. This applies also to trailers being towed by vehicles during the winter. Ideally, however, the tread pattern should be deeper than that.
Winter road conditions
Winter conditions are defined by the presence of ice, snow, frost or slush on any part of the road you will drive on.
Studded tyres or studless tyres?
Different winter tyres have different qualities. When choosing your tyres, you should consider the prevailing driving conditions where you are planning to drive, and choose the tyres that are best suited to those conditions. Winter tyres can be both studded and studless, called studded tyres and friction tyres.
Studded tyres gives you generally better grip on icy surfaces but on a surface with loose snow studless tyres provide the best traction. On hard-packed snow the advantages of studded winter tyres and studless winter tyres are considered to be similar. A summer tyre is never an alternative to a friction tyre because the rubber compounds in summer tyres are not adapted to cold temperatures and therefore harden during the winter. Conversely, the same is true for friction tyres during the summer. The rubber mixture of studless winter tyres is suited for winter conditions.
The difference in road grip between studded and friction has significantly been reduced with the development of tyres; today there are several friction tyres with the same qualities as studded tyres. Most important for driving safely in winter is of course that you adapt your driving style and speed to the road conditions of the roads on which you are driving.
Using winter tyres during summer
It is possible to use studded snow tyres during the summer, but it is of course not recommended. Winter tyres are designed for use during the cold winter and therefore are made of a softer rubber mixture than summer tyres. Summer tyres are safer to drive in high temperatures and during summer conditions. Because of the soft rubber mixture winter tyres wear abnormally quickly when used during the summer months.
Changing the dimensions of the tyres/rims
Changing to a dimension that is not approved for your car might be risky. The general rules of thumb for changing dimensions are as follows:
Tyres and rims should have free space clearance for maximum suspension and steering.
Tyre and rims are covered by the vehicle's fender.
The speedometer shows the correct information, also after the change.
Changing the tyres and rims does not affect the vehicle’s driveability negatively, in terms of, for example, braking capacity, steering capacity or aquaplaning.
However, the dimensions of the tyres and rims should as always be fitted for the car's maximum axle load and speed capacity.
Aging of tyres
Tyres usually hardly age before they are first used. The proper storage of tyres has a positive impact on the aging of tyres, while incorrect storage reduces the tyre's life. It has been shown that a tyre that has been well correctly for 3-5 years still functions properly. The normal aging process starts only when the tyre is used, and when the tyres have been used for 5-6 years you should make a thorough inspection of the tyres and replace them if cracks or damage begin to show even if the tyre still has ample tread depth.
A retreaded tyre is a tyre which is made of previously-used tyres. When a tyre is used, the tread on the tyre always wears down. If the frame of the tyre is intact, then a retreading of the tyre will mean you get a new tread and the tyre can be used again. The technique of retreading tyres has been used for several years. Choosing to retread your tyres is good for the environment as well as your wallet. Retreading provides a reuse of materials as well as a saving of energy, natural resources and money. Only one third of the raw materials required for a new tyre is used for retreading, providing a cheaper price for you as the end user. In our online shop you can find retreaded tyres from suppliers like WinterTact and AGI.
Get more out of your tyres
It is important that you take good care of your newly purchased tyres, partly to minimise wear but also to reduce the risk of traffic accidents. Worn tyres are one of the biggest risks in traffic and one of the main causes of accidents. By checking your tyres regularly, you can gain a few extra years for your tyres while also driving safely on the roads.
Check the air pressure in your tyres regularly. It is recommended that you check air pressure at least once a month. The air in your tyres carries the vehicle's weight and therefore affects the car's road handling. Without the correct tyre pressure the car's driveability is affected and uneven pressure causes the tyres to wear unevenly. Tyre pressure should always be checked when the tyres are cold.
Also check the tread depth on your tyres regularly. Wear indicators in the form of small bumps become visible inside the tread. A tyre should never be used when the tread passes the wear indications (0.06”). During the winter, tyres should have a minimum tread depth of 0.11”. Summer tyres can be driven down to the wear indicators, but it is recommended to replace them before the limit is reached.
Avoid driving into curbs or other forms of chipping. Tyres and rims can obviously get damaged, but also other vital parts of the car. Chipping can affect wheel alignment on your car which leads to uneven tyre wear. Any damage that occurs due to chipping might not be noticeable immediately but can create accidents later while driving.
Rotating front and back tyres
Tread wear on front and back tyres is not equal. Rotating them at regular intervals is therefore advisable. This gives you more uniform wear on all tyres. Remember that the best tyres should always be at the rear.
Checking the wheel alignment
It is very important that all the car's wheels are properly aligned. Improperly aligned wheels affect the car's driveability and cause the tyres to wear unevenly. A regular check-up of wheel alignment avoids uneven or abnormal wear of your tyres.
The Scandinavian tyre & Rim Organization