Tyres are arguably one of the most important elements of a vehicle, however they are often so easily neglected, despite the abuse they can face on a regular basis.
On a daily basis they are worn down through normal use, have to withstand heat and cold and are often bashed by potholes and kerbs, it is no real surprise that they can become easily damaged.
It is for that reason that we must educate ourselves to pay more attention to our tyres, so that we can get the best out of them, and the safest driving experience possible.
It is important that our tyres have sufficient tread to enable them to maintain contact with the road surface in any weather conditions. The grooves in the tyres are used to displace surface content to ensure the tyres grip the road, and so it is only if there is enough of a gap for that surface material, water for example, to go into that the tyres remain efficient.
The minimum tread depth of a tyre is 1.6 millimetres across the central ¾ of the tread around the complete circumference of the tyre. Many vehicle manufacturers recommend replacing at 3 millimetres. At 1.6 millimetres in wet weather it takes an extra two car lengths (8 metres) to stop at 50 mph than if your tread was 3 millimetres. Over or under inflated tyres will cause uneven wear and so the tread might also be uneven, possibly deeper on one side than the other.
We can and should check the tyres on a regular basis to ensure that they are at their optimum inflation and with consistent tread. We need to get close to the tyre and look at each one of them separately. Firstly, we can feel around each tyre with our hands, including the sides, feeling for anything that doesn´t seem correct, such as bubbling or even items protruding from the tyre. It is possible for example for a tyre to contain a nail but the nail is plugging the hole it has made and so deflation can be very slow, despite this potentially dangerous situation.
As we look around each tyre we should also check the tread. If the tyre is under inflated then there may be more wear towards he edges of the tyres. If a tyre is over inflated there could be more wear in the centre. As we work our way around the tyre we should also look within the tread pattern for ridges between the tread. These are called the Principle Grooves and are indicators of tyre wear.
We should check each tyre individually, including the spare, to make sure that the tread wear is consistent and sufficient. We should also check the tyre pressure, although we may have to go to a local service station to do this. Most modern vehicles have a plate stuck to them, often on or near the door, which indicated the optimum pressure under normal driving conditions. If not, you might have to check your manual. You should always check tyre pressure when they are cold.
The tyres themselves also contain a series of numbers and letters which reveals a wealth of technical information. The tyres your vehicle is fitted with are registered on your ITV card, although you can change them for another size with a tolerance up to 3% from the size you have on your ITV card.
If you look at the side of the tyre you will see a sequence which looks something like this sample, “195 / 55 R 16 87V”. Here, “195” refers to 195 millimetres, the nominal section width of the tyre. “55” is 55%, the aspect ratio, representing the height of the tyre sidewall as a percentage of the nominal section width, i.e., in our case, 55% of 195mm. “R” stands for radial construction. “16” is the diameter of the tyre´s inner rim, this time in inches. “87” is the load capacity of the tyre. “V” indicates the maximum permitted speed.
Another code stamped onto the tyre reveals the month and year of manufacture. For example, a code “4108” indicates that the tyre was manufactured in week 41 of the year 2008. There are many cheap tyres on offer for sale which, when you look closely, might well be very old tyres. This is something to be very conscious of, especially as the recommendations are that tyres should be replaced at least every 5 years, so you might not be aware that you are replacing your tyres with those already older than the recommendation.
Because of the importance of tyres and the functions they perform, it is always worthwhile spending that little extra effort, time and even money to ensure they are correct. Garages like Autos Direct in San Miguel will be able to check your tyres for you, if you have any doubt, and can recommend any remedial action you might need to take. However, it is also crucial that we each perform the basic checks mentioned here on a regular basis, at least monthly and every time before a long journey to ensure our vehicles are safe and at optimum performance for fuel efficiency.