Mon, 29 Aug 2005
The tyres on my car are really worn out (and one of them is of a different type, which is probably illegal here), so I have decided to buy a new set of tyres.
Choosing the tyres is more difficult than I could imagine - even if some parameters (such as dimensions, speed and weight index) are fixed, there still remains a wide variety of tyres to choose from (one e-shop had about 35 different types of tyres which still matched my car specifications). So, which parameters are important, and which are not? I have not found any non-biased test or recommendation with exact measured numbers.
Usually the tyre manufacturers state something like that their high-end tyres generate less noise, which results in lower fuel consumption, etc. However, this can be only a marketing speak (read: a lie), or the difference can be too low to justify a higher price. For example - if a set of tyres lasts 50,000 kilometers, with 8 litres per 100 km and a price of 25 CZK per litre (too low, I know) the gas costs about 100,000 CZK, which means that a set of tyres that is 4,000 CZK more expensive should save at least 4% of the total fuel consumption to justify its higher price. Or, would the twice-as-expensive tyre last twice longer than a "normal" tyre?
And then there are purely emotional parameters, such as "this tyre allows you to brake 10% more efficiently in 11mm deep water". Would I ever be in a situation, where this 10% saves me (as in: would I ever drive 0% to 10% over the limit of a "normal" tyre)? And what about 10mm or 12mm deep water? Is this tyre also 10% more efficient than other tyres in 10mm or 12mm of water?
By the way - what is a "normal" tyre? The manufacturers usually compare their products either to their own low-end products (which they obviously can design as badly as they see fit), or to their older products. But what about comparing the products of different manufacturers?
Another factor is a word-of-mouth, and previous experience. One of my relatives had a bad experience with Barum tyres - they worn out to a saw-like pattern which led to higher noise levels. But does this mean all current (or even future) Barum tyres are this bad? And, on the opposite side, does buying the expensive product of a well-known brand mean that my money will not go to the further marketing and advertisement instead of developing better products?
At last I have decided to buy the Dunlop SP 01, because I guess directional or asymmetric tyres can be made better than symmetric and bidirectional tyres. And I got them dirt cheap (even cheaper than Barums are in many shops).