Exploitation is the main factor affecting tyre life – all the more when it is improper. Wrong tyre service, overloading, driving with low tyre pressure and no monthly tyre check seriously damage tyres and reduce the grip of the car, making it a real threat on the road. The proper condition of tyres is the basis for safe driving – how not to miss the right moment to purchase a new set of tyres? How to know if your tyre needs to be utilised?
An important element of tyre inspection is checking them for cracks and bulges. They can mean serious internal damage, which in turn can lead to the tyre expoding while you are driving! Remember that one cannot predict that happening and you never know when you will suddenly have to brake to avoid an accident. When assessing whether the current set of tyres requires replacement, drivers should pay special attention to the tread – check the recommendations of the tyre manufacturer for a tread depth which they deem safe for the given tyre. Tyres with a shallow tread must be disposed of.
– Tyres are the only element of the vehicle in contact with the road and the car’s drivability – also in dangerous situations – depends on their quality. Checking the pressure level, tread depth or searching for traces of bumps and cracks on tyres should be a habit of every driver. It takes no time to do that, but it has an effect on both driving comfort and our efficiency in avoiding accidents or fender-benders during difficult traffic conditions – Piotr Sarnecki, general director of the Polish Tyre Industry Association (PTIA) points out. – Damage caused by improper handling is common – torn tyre beads, which are the element of tyres in contact with the rim, broken sidewalls or improperly balanced tyres. All these damages mean additional expenses to drivers. Let's avoid random auto shops, where the price of services is their only advantage.
Choosing the right tyres
If you need a new set of tyres you should remember that they don’t need to be made in a current year to be considered new. Tyres are not foodstuff, they don’t have a shelf life. Tyres produced a couple of years ago in the right storage conditions do not lose their properties. Physicochemical changes occur mainly during use and are caused by warming up of the rubber compound while operating, tension resulting from pressure, deformations and other factors that do not occur in the process of storage.
How to store tyres? Tyres cannot be stored in direct sunlight or in strong artificial light with high UV radiation, so garden does not make for a good warehouse. Tyres shouldn’t be stored close to heat sources, oil, grease or other chemicals and solvents, because they can negatively impact the quality of rubber compound1. The temperature is also important – we can store tyres at a temperature between 5 and 25ºC. It is therefore easy to recognize an unprofessional auto shop just from the fact that they carry out storage service in intermodal containers, inside of which the air temperature during the winter is the same as outside and in the summer it reaches up to 60-70ºC. For both summer and winter tyres such conditions are damaging. Tyres prepared for storage should be clean and dry. Remember to mark the location on the axles on each tyre before you store them.
One of the most serious mistakes made by drivers is buying second-hand tyres. The tread depth of such a tyre or its leak tightness are only superficial aspects. The biggest problem is the unknown history of their exploitation. It is worth remembering that driving with under-inflated tyres for several hundred kilometres significantly deteriorates the condition of their inner layers, which cannot be assessed with the naked eye. We can never know in what conditions the used tyre was previously operated and stored, and whether or not the car in which it was installed participated in the accident. The use of such tyres increases the risk of unexpected tyre burst while driving, which presents a risk of loss of life or danger to health.
Choosing the right size
The size of the tyre is not just a matter of aesthetics. Each car manufacturer determines the appropriate size for the given car model and the type of engine and approves vehicles for use on the road on such tyres. The information on the proper size of tyres for a given car can be found in the instruction manual of the vehicle. In addition, manufacturers place a string of numbers and characters on each tyre that describe their individual properties, for example 205/55 R16 91T, where:
From November 2012, tyres sold in countries belonging to the European Union must come with appropriate labels. They make it easier to compare the three basic tyre parameters before making a purchase:
Such information must also be provided in e-shops or on bills confirming the purchase.
– In addition to the size of the tyres and the data on the labels, let's also pay attention to other tyre parameters – braking on dry surfaces, drivability on dry and wet surfaces, resistance to aquaplaning, durability and, in the case of winter tyres, driving properties in winter conditions – says Piotr Sarnecki. – Such information can be found in many independent tyre tests, where these key parameters are compared – adds Sarnecki.
1 Such are the recommendations of European Tyre and Rim Technical Organisation ETRTO from 2008