Archive for July, 2010

Car Tyres Teasers – Important Facts You May Not Know

Monday, July 12th, 2010

‘We’re on your side.’ This sounds like the tag line in an advertisement but here it refers to the codes on a car tyre’s sidewall. Most of us know the obvious ones like those referring to wheel diameter and tyre section. There are, however, many other pieces of vital information to be found, moulded into the sidewall. Let’s consider some of the more important ones.

Did you know that some car tyres have a marked rating that indicates how well they handle heat build up? If you see a mysterious “A” on a tyre, it has the highest rating. A “C” denotes the lowest.

The traction rating shows how well a tyre can stop you on a wet road. This rating goes from “AA” to “CC”. No prizes for guessing which is the best.

Now for some numbers. Tread wear ratings go from 60 to 600 in increments of 20 and the figure shows how long the tyre is expected to last. In theory, a tyre marked “200″ should last twice as long as one marked “100″. This is, however, a relative rating. The actual tyre life will depend on many factors, including your driving style, the road surfaces encountered, correct wheel alignment and the right tyre pressure. Think ‘benchmark.’

The speed rating a tyre carries is extremely important. Using over-specified tyres is a (very expensive) upside here; tyres for high-speed use can be used at lower speeds. On the other hand, if the speed rating is too low and you have an accident, your insurance company may take a dim view of the tyres your car was wearing at the time. Speed ratings run from “L” (75 mph) to “Z” (150 + mph). Currently, H-rated tyres (130 mph) hold the largest percentage of new tyre sales.

So much for speed, what about load? Yes, car tyres tell you about the load they are capable of carrying, They have a marked load index (LI), which is valid for sub-130 mph speeds. Load indices range from 50 (190 Kg) to 169 (5,800 Kg) but the calculations are a touch complex. Let’s say you have a car that weighs 2 tonnes, or 2,000Kg. Divide this by four to get the weight on each wheel; this equals 500Kg. So far so good, but, do you know that all four wheels carry 500Kg or is one end of the car heavier than the other? In practice, it’s usual to add a percentage to cover such factors.

In our example, then, the car needs tyres with a load index of 84. We can add 20 percent, giving a weight bearing capacity of 600Kg. Therefore tyres with a load index of 90 will do very nicely. In reality, a car tyre’s load rating will exceed its actual needs by a long way. However, when speeds reach 130 mph or more, the load index calculations change dramatically. For reasons far to technical to explain here, the theoretical load rating decreases as road speed rises. In the event you run a very, very fast and heavy car where the speed cameras don’t work, there are experts in such matters. Find one!

Lastly, you should never use a tyre more than 6 years old. The date of manufacture is part of the DOT code marked on one sidewall. For example, a tyre marked “2709″ was made in the 27th week of 2009.

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Merityre.co.uk are one of the  leading UK independent suppliers of car tyres. Why not visit their website for an online tyre quote or contact your nearest fitting centre.

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A Matter Of Choice – Selecting The Optimum Car Tyres

Tuesday, July 6th, 2010

Car tyres are car tyres, right? Well, they’re all round, black things that go between your wheels and the road. However, choosing the right tyres for your car and, equally important, for your needs is imperative. Here are some pointers to help you make the right choice.

The Right Type of Tyre

There are five distinct tyre types you can choose from and it isn’t always a case of one tyre type for one car; the choice is also about usability.

Standard car tyres, otherwise known as all-season tyres, are the least specialised. They are suitable for year-round use, in wet or dry conditions. In some respects, run flat tyres lie in this arena. Run flat tyres can do exactly what their title suggests; you may continue using them, albeit at a given maximum speed over a specified mileage, even after a puncture.

The third variety of car tyres differs in the conditions to which they’re suited. Winter tyres can handle colder conditions better than standard tyres and they generally have a tread pattern with larger blocks in a more open pattern, for better grip. Our fourth tyre type is also based on the conditions to be encountered, specifically in terms of terrain, rather than climate. All-terrain tyres can cope with mud, sand and gravel and are often found on 4×4 vehicles used off the road. However, the additional grip in adverse conditions has a cost. All-terrain tyres are noisy when used on ordinary tarmac roads.

Lastly in this quintet, performance tyres are for performance cars. As well as offering superior grip in wet or dry conditions, performance car tyres usually have a higher speed rating.

The Right Tyre Size

When it comes to car tyres, it is anything but a matter of one size fits all. The manufacturer’s recommended fitment may be found in your car’s handbook and if in doubt, you could always have replacement tyres like the existing ones. However, small changes in tyre section and width can be accommodated, often beneficially. The staff of a good car tyre retailer will be happy to recommend the best tyres for you.

The Right Tyres for your Driving Needs

While remaining within the manufacturer’s specified parameters, you can ring the changes by using car tyres that suit your driving style and/or particular needs. You may need economy tyres for better mileage from your gallon. Certain tyre types are particularly quiet in use and therefore better for motorway use. Similarly, some tyres are well suited to stop/start motoring. As mentioned above, you’d be well advised to consult the tyre retailer.

The Right Price

The price of car tyres varies considerably but here, commonsense must play an important role. You can’t for example, have economy tyres fitted to a high-performance sports car and expect good results, not to mention longevity. Conversely, there’s little point in having high specification tyres fitted to a car that covers a small yearly mileage. However, if you use your car daily, economy tyres could represent false economy; budget tyres may not last as long as better quality items.

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Get an instant online tyre quote now or contact your nearest fitting centre to see how much you can save with Merityre car tyres specialist!

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