How to read a tyre sidewall

• 215: Tyre width in millimetres.
• 60: Tyre aspect ratio. Ratio of height to section width.
• R: Construction = Radial
• 17: Internal diameter in inches.
• 100: Load Index. The load index is a code showing the maximum load a tyre can carry at the recommended pressure.*
• T: Speed Index. The speed symbol indicates the maximum speed of use under service condition specified by the tyre manufacturer.

*Maximum load corresponding to the Load Index (LI)

Other marking:

• Brand name: e.g. RIKEN
• Tyre Range name: e.g. Ultra High Performance
• 3PMFS: Sidewall symbol of tyres for use in severe snow conditions. Tyres with the '3 Peaks mountain Snow Flake' marking have been tested and offer snow performances confirmed by regulatory snow tests.

• M+S: Tyres with Mud & Snow marking are snow tyres according to European rulings, the snow performance under winter conditions have not been subject to testing.

• Tubeless: This indicates that this tyre does not require an inner tube.
• Manufacturing information: Tyre Identification Number (TIN) is composed of 8 to 12 digits, please read further for the detailed explanation.
  • T5: Factory code where the tyre was made (code is 2 or 3 digits)
  • 1C: Tyre size code
  • 01YX: Manufacturer construction code (optional)
  • 4416: Week and year of manufacture
• European regulation marking:
  The 'E' and 'e' markings with the approval numbers marks the compliance with ECE 30 ruling and 2001/43 EC directive and tests associated.
  These markings are mandatory for commercialization in EEC countries.

• INMETRO:
  The INMETRO marking with approval number marks the compliance with Brasil’s regulations and associated approval tests.
  These markings are mandatory for commercialization in Brazil.

• NOM:
  The NOM marking marks the compliance with Mexican regulation and associated approval tests. This marking is mandatory for commercialization in Mexico.

• Uniform Tire Quality Grading (UTQG)
  UTQG was established by the National Highway Traffic Safety Administration (NHTSA) to test tyres following government prescribed test methods.
  • Tread wear:
    Grades are based on actual road use A grade of 100 would indicate that the tyre tread would last as long as the reference CMT tyre, 200 would indicate the tread would last twice as long, 300 would indicate three times as long, etc.
  • Traction:
    Grades are based on the tyre's straight line wet coefficient of traction. The UTQG traction test does not evaluate dry braking, dry cornering, wet cornering, or high speed hydroplaning resistance.
    Traction grades are AA, A, B and C (with AA being the highest grade). Any tyre rated under C is considered unacceptable for road travel.
  • Temperature (Resistance):
    Grade indicates the tyre’s ability to dissipate heat under controlled indoor test conditions. The temperature grades, from highest to lowest, are A, B and C. Any tyre rated below C is considered unacceptable.

• Tyre structure:
  This branding on the sidewall of a tyre list the materials and number of layers of each material used to reinforce the rubber in the tread and sidewalls.

European tyre labelling regulation

The European regulation has introduced labelling requirements based on actual testing to display information on fuel efficiency, wet grip, and external rolling noise. Its aim is to increase safety; the environmental and economic efficiency of road transport by promoting fuel-efficient and safe tyres with low noise levels. This regulation encourages end-users to make more informed purchasing choices. Consumers should be made aware that the actual fuel savings and road safety depend heavily on driver behaviour, speed, and road conditions. Furthermore, tyre pressure needs to be regularly checked and corrected for optimum fuel efficiency and grip performances.
This European regulation is evolving and gradually pushes the tyres towards better performances for rolling resistance, wet traction, and noise. Accordingly, fuel efficiency 'G' class and wet traction 'F' class are no longer sold in the European market since November 2014.

Fuel efficiency

7 classes from 'G' (least efficient), to 'A' (most efficient).
The effect depends on the vehicle, driving conditions, and speed; but the fuel consumption differences between an 'A' and a 'G' set of tyres could be up to 5%. It may represent up to 150 euros per year.

Wet Grip

7 classes from 'G' (longest breaking distance), to 'A' (shortest breaking distance).
The effect depends on the vehicle and driving conditions: in wet conditions the difference between an 'F' and an 'A' class set of tyres could be up to 18m of braking distance.

External Rolling Noise

In addition to the noise value in Decibel (dB), a pictogram displays whether the tyre external rolling noise performance is above the European limit value (more black bars = noisier tyre), between the limit value and 3dB below (2 bars = average noise) or more than 3dB below the limit value (1 black bar = low noise).
The decibel scale is not linear: reducing the noise level by 3dB has the same effect as dividing the intensity of the noise source by 2.

Specific labelling has been created in some countries as Saudi Arabia (SASO) and Gulf states (GCC) countries with similar performances associated with different thresholds.

The choice of a tyre must conform to the legislation, in line with the equipment recommended by the vehicle and tyre manufacturer or by an official organisation (size, load and speed indices, tyre structures, etc.).

Depending on the legislation in force and for technical reasons, it is either mandatory or strongly recommended to use tyres of the same type on the same axle.

By “tyre type”, European Regulation means tyres which do not have significant differences between them, in particular relating to:

• the manufacturer;
• the tyre size designation, speed index , and load index;
• the category of use (road use, snow, temporary use);
• structure (diagonal ply, radial, runflat).

It is recommended that tyres of comparable wear are fitted on the same axle. Some country level legislations set maximal differential on tread depth.

In case of buying used tyres we recommend asking a tyre professional to check them.

A temporary spare tyre must not be used on a long-term basis or above the maximum speed indicated on the tyre or wheel. It should only be used in accordance with the tyre and vehicle manufacturer’s instructions. Care should be taken when driving a vehicle with a temporary spare fitted, as the vehicle’s handling may be affected.

General conditions

Storage should be

• Away from any chemical substances, solvents or hydrocarbons likely to interfere with the nature of the rubber
• Away from any object that could penetrate the rubber (e.g. sharp metal)
• Away from any source of heat, flame, incandescent object, material that could cause sparks or electrical discharges and any ozone sources (transformers, electric motors, welding devices, etc.)

Avoid crushing tyres under other objects.

Any tyre stored outside should be cleaned and dried before fitting.

Accessories must be stored in their original packaging, on surfaces that do not present any danger of cutting, tearing or perforation. In all cases, tyres and accessories must be handled with care.

Short-term storage

(up to 4 weeks)
Tyres can be stacked one on top of the other, preferably on pallets. However, the height of the stacks should not exceed 1.2 metres due to the potential instability of the pile.
If a tyre have been distorted, keep it unstacked for 1-2 days so the tyre could return to its normal shape.
When fitted on rims, tyres should be stored inflated, in an upright position on racks or in a single layer on shelves.

Long-term storage

Tyres should be stored upright on racks with no direct contact to the floor.

CHECKS

General recommendations

Any perforations, cuts or visible distortion of the tread, sidewalls or bead area must be checked by a tyre professional to assess if the tyre can continue to be used, need to be repaired or is irreparable.
Any damage to the rim must also be checked by an appropriate expert.

Never put back into service any tyres:

• with visible damage, such as a deformed bead, rubber or ply separation, visible bead wire or bracing plies, damage from hydrocarbons or corrosive materials, marbling or abrasion of the interior rubber resulting from running at low pressure.
• when there is any doubt about their condition or suitability for service.
• which do not comply with legal requirements, for example tread depth below tread wear indicator (TWI).

Each time the vehicle is inspected, check that the valve cap and its rubber seal are in good condition. If in doubt, replace the cap with a new one.

Checking for wear

Checking for wear must always be carried out at several points across and around the tyre.
This check can be carried out using a tyre tread depth gauge or by referencing against the tread wear indicators in the tread grooves. The tread wear indicators (TWI) are located in the main grooves in line with the TWI symbols in the tyre shoulder area.

TWI marking on the shoulder area indicates the position of the Tread Wear Indicator in the groove of the tread pattern.

In precedent tyre lines, the TWI marking was a triangle.

If the legal limit for wear has been reached, the tyre must be removed and replaced.
We recommend you to consult with a tyre professional if there is abnormal wear or a difference in wear between two tyres on the same axle.

Tyre inflation pressure

Given that a tyre slowly loses inflation pressure naturally, it is necessary to adjust it quarterly; this check can also enable any abnormal loss of pressure to be detected.

This check must be carried out on all the vehicle’s tyres (including the spare when there is one).

• Under-inflation

  The use of a vehicle that has tyres with insufficient inflation pressure could lead to an abnormal increase in their operational temperature and may cause damage to internal components. This damage is irreversible and may lead to a sudden rapid deflation of the tyre. The consequences of running with insufficient tyre inflation pressure are not necessarily immediate or visible, and may appear even after the tyre pressure has been corrected. Insufficient tyre inflation pressure also strongly increases the risk of aquaplaning.

• Over-inflation

  Over-inflation can result in increased susceptibility to impacts (e.g. tread damage).
  Over-inflation or under-inflation can cause rapid and irregular wear.

It is recommended that tyre pressures are checked when tyres are cold.
If the check is carried out after driving and the tyres are warm, the tyres should not be deflated as inflation pressure increases with temperature. In case of warm tyres, we recommend to adjust the pressures using a pressure of 0.3 bar higher than the cold pressures recommended by the vehicle manufacturer

Inflation with nitrogen is not an exemption from the need to check tyre pressure regularly.

In all circumstances, keep the pressure level recommended by the vehicle manufacturer or alternatively by the tyre manufacturer.

REPAIR

Tyre damage often cannot be repaired.
All tyres must be inspected and repair carried out by a trained and qualified tyre professional.

In order to check if a tyre that has been run underinflated or flat and may have suffered irreversible damage, the tyre shall be removed from the wheel. It should be inspected to define the type of repair required.

Key points

Tyres with the following visible signs cannot be repaired:

• Bead wire visible;
• Steel belts separated or visible;
• Sidewall worn out due to run flat and sidewall touching the road;
• Obvious signs of under-inflation or run flat (visible from inside).

The inner liner is showing cracks due to run flat.
This is an irreversible damage, the tyre cannot be put back in service.

Presence of powder:
The inner liner has been destroyed, it is likely that the body ply has also been damaged; thus, the tyre cannot be put back in service.

Tyre repair basics

The professional repairing the tyre is responsible for

• the inside examination to ensure that there are no inside damages.
• the quality of the repair (ensure air tightness and full obturation of the hole).

The professional has to evaluate properly if the tyre could be repaired

• without any risk related to potentially existing irreversible damages due to run flat (can only be checked from the inside).
• whether the location of the damage is in the repairable zone (see below).

Repair material

• For tubeless passenger or light truck tyres, the use of Mushroom type repair patches (cold repair) is highly recommended.

  Repair with plug are also acceptable provided that tyre have been dismounted and analysed for potential run flat damages.

  These two type of repair ensure the full obturation of the hole and then limit the risk of further corrosion of steel belts.



• Simple patches are not recommended, they must be avoided because of potential corrosion of the belts.

Mushroom type patches are recommended.

Simple patches are not recommended.

Use of sealing products

• In the event of a puncture, injection through the valve of sealing products (instant puncture sealant, etc.) can only be a partial and temporary solution. These chemical products can cause technical problems with the tyre, wheel, valve, pressure sensor, etc. It is essential to follow the sealing products manufacturer’s recommendations.

• We recommend you to go to a tyre specialist to closely check the tyre, repair it properly or replace it if needed.

Never use the tyre beyond the limits of the technical specifications for which it has been approved.Poor use or wrong choice of tyre can also contribute to premature wearing of certain mechanical parts.

New tyres to the REAR

When replacing just two tyres, we recommend that the new or least worn tyres are fitted to the rear axle for improved vehicle control and safety. This advice applies to front and rear wheel drive vehicles fitted with the same tyre sizes front and rear. Ensure that the tyre inflation pressures are readjusted to comply with the vehicle manufacturer's recommendations.

Specific cases:

• 4 wheel drive vehicles:

We strongly recommends, just as the vehicle manufacturers, that whatever the type of 4x4 system, tyres are fitted in identical sets of 4 (same size, same range, same manufacturer reference, and the same level of wear). An exception is where the vehicle was originally fitted with different tyre sizes front to rear.

This recommendation is because differences in rolling circumference between the front and rear tyres could lead to premature damage of transmission components, such as a drive shaft in a part-time 4x4 system, or the centre differential in a full time or automatic 4x4 system.

To maintain similar wear levels between the front and rear tyres, it is strongly recommended to:

• Replace all 4 tyres at the same time.
• Periodically rotate the tyres front to rear in accordance with the manufacturer's recommendations.

Also, the vehicle manufacturer’s tyre pressure recommendations must be followed to avoid pressure-related differences in rolling circumference that could lead to premature damage of mechanical components.

Introduction

Correct fitting, performed in accordance with recommended operating procedures and complying with the safety rules in force, ensures excellent protection for people and material, and allows the tyres full potential to be exploited.
Poor fitting or non-respect of recommended practice can cause damage to the tyres, the vehicle or to people (serious, even fatal injuries).
It is therefore essential that these operations are carried out in a tyre shop by people who have been trained and who have the appropriate equipment available.

General precautions

If a trainee carries out any part of the tyre fitting procedure, he/she must always be closely supervised by a qualified tyre professional.

In all cases, it is essential to refer to the technical instructions of the tyre manufacturer, vehicle manufacturer and wheel manufacturer, as well as the user manual for the tyre-fitting machinery or equipment.

Operators must:

• Always wear their normal protective clothing (gloves, safety shoes etc.)
• Must have access to an operating procedure.
• Ensure that the vehicle engine is switched off and that the vehicle is properly stabilised (handbrake, blocks, supports, etc.).

Precautions for removing the wheel from the vehicle

In the case of dual (twinned) fitments or if the rim shows evidence of damage, the tyres must be deflated before removal of the fitment assembly.

Ensure that the wheel and tyre are cool enough to allow safe removal.

Comply with the manufacturer’s recommendations and instructions.

Precautions for fitting

Check that the tyre and wheel are of the correct dimensions, are compatible with each other and are compatible with the vehicle's conditions of use.
Check that the tyre, the wheel and its components are in good condition and suitable for service before fitting.
Respect any fitting instructions on the tyre sidewalls (fitting orientation or direction of rotation for example) and ensure the tyres are fitted to the correct positions on the vehicle.

Rubber valves must be systematically replaced in tubeless applications.
Metallic valves must be checked for condition and air tightness. Replace the valve or seals where necessary.
After fitting the assembly to the vehicle, it is important to use a suitable calibrated torque wrench and installation method to tighten the nuts to the torque specified by the vehicle manufacturer.

Precautions for inflation

Correct tyre inflation is an essential factor, not only for optimal tyre performance but also for SAFETY.
It is necessary for correct vehicle handling (road holding and braking) as well as for maintaining tyre condition.

Only use inflation equipment intended for this purpose and fitted with a pressure limiter. In no event must a person or operator be in the immediate proximity of the equipment in order to be out of the path of any potential discharge in the event of an incident.

Tyre operating inflation pressure

Comply with the tyre inflation pressures recommended by the vehicle manufacturer. These can be found:

• On the vehicle itself – on the door, door frame, fuel filler cap, etc... or
• In the vehicle user manual, or handbook, or if not, refer to the tyre manufacturer’s recommendations or professional guide.

Under-inflation or excessive over-inflation can significantly alter the vehicle’s handling and tyre performances.

Balancing

If the fitted assembly is not correctly balanced (dynamically), it may induce vibrations into the vehicle during service.

It is therefore essential to balance all four wheels for a comfortable drive and for sustained vehicle and tyre performance.

For effective wheel balancing, the balancing machine must:

• Have a centring system matching that used on the vehicle hub,
• Be calibrated in accordance with the manufacturer’s instructions.

These two points are critical to the quality of the work carried out, and are often at the root of faulty balancing.

Lack of or faulty balancing manifests itself in the form of vibrations in the vehicle, within various speed ranges. It is therefore essential that these operations are carried out in a tyre shop, by people who have been trained and who have the appropriate equipment available.

Tyres are made from different types of reinforcement materials and rubber-based components, whose properties evolve over time.

For each tyre, this evolution depends on many factors, such as climate, storage conditions (temperature, humidity, position, etc.), conditions of use (load, speed, inflation pressure, road damage, etc.) to which the tyre is subjected during its working life.

These ageing factors vary so much that it is impossible to predict the life of a tyre with any accuracy. This is why, in addition to regular user checks, it is recommended to have the tyres regularly checked by a qualified professional, who will determine whether the tyre is fit to continue in operation.

The older the tyre, the more probable it is that it may be necessary to replace it due to ageing related to its storage and/or usage or because of other factors established during checks.

As a precaution, even if their condition appears to be acceptable and they have not reached the legal wear limit, we strongly recommend systematically replacing tyres 10 years of age or more based on the date of manufacture [including the spare tyre if any].
The tyre’s date of manufacture can be determined from the last four digits of a code on the sidewall. [See the TIN in section "How to read a tyre"]