Why you should avoid vehicles with run-flat or spacesaver tyres:
Flat tyres are a pain and no one likes to deal with them, but they are generally not hard to change and not all that expensive to fix – at least until recently.
Now carmakers are starting to sell cars with run-flat tyres and no spare wheel – when you have a puncture you simply keep driving to the nearest tyre shop and replace the whole tyre, at a cost of several hundred dollars. Once these run-flat tyres have been driven flat you are not legally allowed to use them on the road again. These tyres are designed for Europe and Japan, where convenience is everything and there’s always a tyre shop nearby. However, run-flat tyres can only be safely driven between 80 and 150 kilometres and there are plenty of places in New Zealand and Australia where there’s no tyre shop within that range.
Imagine you’re on your way to a wedding late one Friday night, travelling between two distant cities. There may not be an open tyre shop for 500 kilometres or more. That’s assuming that the tyre shop has a suitable replacement tyre when you get there. Right now, on makes like BMW, you’ll probably have to get your tyre from a BMW dealer. How many BMW dealers do you think are open on a wet Sunday night? There’s a spot on Australia’s Highway One where you are 2000 kilometres from the nearest BMW dealer.
European carmakers are quick to point out that punctures are relatively rare and that many motorists don’t like changing wheels. Indeed they don’t, but most motorists would at least like the option of having a wheel to change if they’re stuck in the middle of nowhere.
There are also numerous reports of run-flat tyres wearing out alarmingly quickly, requiring the replacement of all four tyres at low mileage. Other owners complain of vibration and poor handling attributed to the run-flats.
Run-flat tyres aren’t even particularly clever. They’re simply a conventional tyre with a self-supporting system inside, to keep the wheel from going flat if it gets a puncture.
Car companies promote run-flat tyres as a gift to the consumer, pointing out their safety and convenience. This is basically crap. Run-flat tyres were developed so that carmakers could increase boot space, save weight and avoid paying out for a spare tyre, jack and tools. Our only sane advice is to simply avoid cars with run-flat tyres.
Almost as bad are ‘spacesaver’ tyres, supplied with most Japanese domestic cars and many local models. Basically spacesavers are a small, thin tyre that is designed to get you to the nearest tyre shop at low speed. Tests by The Dog & Lemon Guide on a racetrack show that cars fitted with spacesavers handle very poorly and are difficult to control at even moderate speeds. Spacesavers have already been linked to at least one fatality. There’s no valid reason for spacesaver spares – they’re simply another cost-saving exercise at your expense.
At least you can do something about spacesavers: don’t buy new cars with one, or insist that the dealer replaces the spacesaver with a conventional tyre. In many cases there’s enough space in the boot to fit a full-size wheel. If there’s not you may need to work out some way of restraining the larger tyre when it’s in your boot. However, given that your life rests on your tyres, the extra hassle seems well worth it.作者: hare 时间: 2012-6-12 22:25:06