Legal but Lethal... A Brief Look at Tyre Topography for the Uninitiated

Next to the Engine and Under-Bonnet kit, Tyres are probably the most neglected item of most cars. A tyre is a living breathing organism which can expire rather like a human if abused and ignored. However, with just a little effort on the driver's part, safety and economy can be preserved.

Basically there are three parts to a tyre. The Tread; The Sidewall; and the Tyre Pressure.

Starting with the pressure; it is essential that you know what the correct setting for your particular tyre is and that you check them regularly. Every week or every 500 miles (800 kms).The correct pressures can be found in your Owners manual or if this is missing then have a look inside your fuel filler cap or door jam.

Since many Garages seem to have great difficulty in maintaining all their forecourt equipment, the best option is to invest in your own little compressor which will work from your cigarette lighter connection. You can then check your tyres when they are cold, which gives you a true reading and spot irregularities easily. I gave up driving miles to my regular Petrol Station years ago because the air line and the car wash were constantly out of action. Garages take note!

The Tread depth is an important consideration for all drivers. First you have the legal limit which is??? . Worth pointing out here that tyres on the legal limit are 85% worn out so do your math and have a guess at what sort of adhesion you have while driving. In the dry you may be ok but in the wet you will be in a perilous condition. So remember my phrase ..........."Legal but Lethal"

Tyres wear at a different rate depending on which axle they are on. What does this mean? Well, since the front wheels do all the work and support the heaviest part of the car, the power plant, aka Engine, the front tyres wear out twice as quickly as those at the rear. A useful tip here is to switch the tyres round periodically to even out the wear.

Your tyre shop will do this for you when you are in getting a puncture repaired, your wheels balanced or tyres replaced. Remember your best tyres should always be at the front. Why ...well they do all the work whereas the rear tyres just pose and go round and round in circles!

The Sidewall of the tyre is the most vulnerable since it is often in contact with the Kerb, potholes and other nasties. The depth of the sidewall is quite thin hence it's very easy to destroy a tyre by thumping a kerb so keep your distance. A regular check on the sidewall for cuts splits and bulges is important and if you find any of these then you should replace the tyre immediately.

All of these checks form part of the new Technical Check questions you will be asked on the Irish Driving Test. So get used to becoming an Informed and Aware, Learner Driver, instead of an Air Head!

Of course the fact that these technical questions have appeared as part of the Driving Test in Ireland is rather pass