Low profile tyres offer better cornering ability than the old 100 percent variety - and the markings on a tyre give a lot of information. For example, 185/70 VR 15, means the tyre is 185mm wide and has a 70 profile on a 15-inch wheel. The VR means it is suitable for speeds up to 240kmh.
However, with 50 and lower tyre profiles, there are certain dangers to be avoided. To my cost I clipped the kerb in my Mercedes SLK and although damage to the rim was negligible, the tyre had a small chunk gouged out of the sidewall making renewal necessary.
OK, my fault for misjudging the distance from the kerb; my only excuse is that visibility on the SLK is very bad all round. No wonder most owners fit the radar parking devices. As a confirmed skinflint, I neglected that option and am now seriously considering it.
Checking all tyres visually at least once a week is recommended and every couple of weeks they should be checked with a decent tyre gauge. On many cars, the SLK included, a warning comes up on the fascia to tell you when even one tyre has lost pressure. It is then necessary to put in air.
Low profiles must have correct pressures if they are to do their job efficiently. The tread is flat and too high a pressure makes for a convex shape. Conversely, under-inflation leads to a tread with a hollow contact patch. Both mean a reduction in cornering ability and rapid wear.
Tyre makeup and design has come an incredibly long way over the past 20 or so years to keep up with the high performance, rapid acceleration and incredible braking of modern vehicles, but correct pressures are essential.
Fuel saving is a big selling point on any vehicle and tyres play an important role in achieving this. Modern tyres may be considerably lighter than earlier ones. Rolling resistance is another important factor to be considered. As a tyre rotates under load the side walls flex, as does the tread itself. Every bit of flexing costs energy and increases fuel consumption. Special compounds have brought a big reduction in rolling resistance and that benefits us all.
What sort of tyres you buy should largely depend on the car you drive and how fast you drive. It would be a waste of money to go for, say, a VR rated tyre for your ancient Morris Minor, but equally it would be dangerous folly to fit tyres with an S symbol (180kmh) to a car capable of 270kmh.
Insurance companies would not look kindly on an accident claim where high speed was involved but the tyres were unsuitable for it. Used tyres may be fitted if cash is in short supply, but vet them carefully. Get alignment professionally checked when new tyres are fitted and at least once a year regardless. Examine treads and walls regularly for signs of wear.
Above all, when buying get several quotes. There are often specials available that offer big savings. -Star Motoring