Tyres

THE new Holden Captiva I bought in 2008 also required four new tyres in less than 15,000km of useage. This is because of incorrect camber settings since new which resulted in each tyre being severely worn on the inner sides.

MY 2008 Ford Mondeo TDCI tracks on some roads. It's fitted with Goodyear Excellence 235/45/17 tyres. I have had the Goodyear agent do a wheel alignment, but the problem still occurs. Is it because the tyres are asymmetric, or perhaps the low profile? If it is the former, should I replace them, when replacement is required, with regular symmetrical tyres? Can you help?

It was the first in a very long time, and the first I can remember when I was not doing something silly like driving down a rutted forest track making pacenotes for a rally.  This time I was driving an Audi TT RS and there was no warning. No pop, no bang, nothing nasty on the road, but when I got home the left- rear tyre looked a little unhappy.Less than 30 minute later the rim was down to the road and I knew I had a problem.  At this point, having paid more than $130,000 for their hot new German coupe, the vast majority of TT RS buyers would pull out their iPhone and call the Audi emergency number.But I resist the temptation and decide to investigate the brave new world of 21st century tyre changing.  Except there is no way to change a tyre on a TT RS. It doesn't even have a jack.Instead, it has a compressor you plug into what was the cigarette lighter - now called the power socket - and a can of pump-in tyre sealant goo. But there is a wheelbrace.Since this is an experiment, I borrow a jack from another car and remove the wheel to check the puncture, discovering a nine-millimetre cut through the tread.  I'm not optimistic - I can still remember a nasty motorcycle flat and a can of useless goo in the 1980s - but I hook up the repair kit and pump away. And the tyre inflates and the rush of air from the slash slows to a dribble . . .It's a good effort and I'm impressed. The tyre holds on the run back to the Audi dealer for a replacement.  I'm still not entirely happy, and I would prefer a spare in any car, but the pump-up repair seems like a reasonable system and it means you don't have to suffer the harsh ride of far too many runflat tyres.Follow Paul Gover on Twitter!

Most people regard tyres as a grudge purchase, to be done as cheaply as possible, but a new national survey confirms the expert view that quality tyres are worth the extra.  Really cheap buys - such as no-name Chinese imports - have been exposed through the research.A Beaurepaires survey found that better tyres can also reduce stopping distances by up to 7m compared to cheaper ones.  Beaurepaires marketing manager Melinda Wood, says a tyre's quality, as well as its inflation, tread depth and condition, greatly influence its ability to stop a vehicle in an emergency.Good tyres can mean the difference between having and avoiding a collision, she says.  With the Christmas holiday season about to start, motoring organisations like the RACV are recommending that drivers check their tyres for the correct inflation pressure, any defects and the whether they are roadworthy. Brakes should also be checked.A Victorian Automobile Chamber of Commerce survey recently found that 25 per cent of Victorian vehicles would fail a five-point safety check involving tyres, steering, seatbelts, headlights and brakes.RACV research has found that more than 20 per cent of all vehicles on Melbourne's roads are driving on at least one unroadworthy tyre and that one in five vehicles have under-inflated tyres.  An unroadworthy tyre is one with a tread worn below 1.5mm or has been physically damaged.The RACV's chief engineer, Michael Case, says cheaper tyres are often a false economy.  "In general you get what you pay for," he says."Cheaper tyres are not necessarily a bargain because they don't last as long."Case says that the economic downturn has forced many motorists to neglect vehicle maintenance or resort to budget imported tyres.  "Anecdotally there is a connection between the economy and vehicle maintenance," he says.The RACV's own tests have shown that a car travelling at 60km/h on worn tyres will need an extra 3.9m to stop.  The Beaurepaires survey found that just one in eight drivers (12 per cent) understand that premium tyres are safer."More worryingly, many drivers think there is little difference in stopping distances between premium and cheap tyres - 33 per cent think this stopping advantage is less than 6m," Wood says.  Women are more likely than men to underestimate the stopping distance advantage of premium tyres.Almost two in five women (38 per cent) consider the difference in stopping distance advantages between premium and cheap tyres to be less than 6m, compared to 28 per cent of men.Beaurepaires tyre experts tested 16 different sets of tyres, from many leading brands, in both wet and dry conditions.  Dunlop and Goodyear - distributed by Beaurepaires - were the best performers, stopping up to 7m earlier in the wet than the other tyres.These same tyres also led the way in dry conditions, with almost 2m on their competitors.  Stopping distance depends on several factors like reaction times, speed, driving conditions, and the condition of the tyres and brakes.Under-inflated tyres will also significantly affect a vehicle's handling and ability to stop in an emergency.  Drivers unsure about the condition of their tyres should have them checked by an expert.  Most reputable dealers have free safety inspections.Recommended Stopping Distances:Speed/Stopping Distance40 km/h/37m60 km/h/55m80 km/h/82m100 km/h/116mTyre Tips1. Check tyre pressures regularly2. Replace any worn or defective tyres3. Have tyres balanced and steering alignment checked 4. Check your spare tyre is correctly inflated and roadworthy 5. Practice how to change a tyre

AS ANOTHER of your readers has reported, I too have had the rims on my BMW X5 Sport crack in normal driving situations, and I know of two others who have had the same problem. BMW says they have never had any complaints, but I find that hard to believe. I had the cracked rim examined, and was told by the company who checked it that they had seen it before. As far as BMW customer service goes, that leaves a lot to be desired.

I FEEL the front tyres on my Renault Laguna are wearing very poorly. The wear is not even and it's quite heavy on the outer edges. At 10,000km I requested the front tyres be rotated to the rear and that the wheel alignment be checked, but the ``new'' front tyres have worn again. I have had the wheel alignment checked -- it was found to be spot-on -- and have increased the tyre pressure without any improvement. One tyre dealer told me the wear was normal for low-profile tyres such as the Continentals fitted to my car. Is this correct?

That’s because the rolling resistance of tyres sucks up about 20 per cent of what pours down the bowser hose.So tyre companies are taking a significant role in the growing search for better fuel economy.The latest to join in is Korean manufacturer Hankook with their enfren – short for ‘environmentally friendly’, apparently – a new range which incorporates specially bonded silica.Hankook says independent testing in Europe showed the enfren had a rolling resistance of 8.32, where a conventional tyre had 10.54, meaning a reduction of 21 per cent.When that 21 per cent is deducted from the 20 per cent of fuel used up by rolling resistance, it means you’re using 5 per cent less fuel overall.The European results were repeated last week in testing at Eastern Creek outside Sydney, with the enfrens facing off against a set of conventional steel belt radials.Taking just over four hours on identical Hyundai i30 SLX CRDi hatches, the test resulted in the conventional tyre using 22.13 litres (5.79L/100km) while the enfren used 21.06 litres (5.51L/100km).We were given the chance to try the enfrens through a series of slaloms, corners sets and brake tests around the track, but weren’t able to compare it to other low rolling resistance tyres at the track.We ran an informal – and fairly unscientific — comparison with the enfrens on the manual Hyundai diesel hatch against a set of conventional tyres on a Mazda6 manual diesel hatch. This showed that understeer entered earlier with the enfrens, but not by much, and some of the time difference would be attributed to the difference in wheel size: 16” on the Hyundai and slightly wider 17” on the Mazda.The enfrens also added a couple of metres to the stopping distance at 70km/h, but at no time did they feel unsafe or out of order for what would be normal circumstances.And the fuel saving makes them worthwhile, according to automotive industry engine consultant John Cadogan, who says they are a cost-effective solution for fuel economy.“Car companies should jump at the chance for a five per cent solution,” Cadogan says.“Rolling resistance is an easy to tackle, retro-fit, bolt-on solution with a direct correlation between consumer and environmental benefit."“The link between fuel and CO2 is absolute, you can’t reduce CO2 by any other way than to reduce fuel consumption.”Cadogan says that lwo rolling resistance tyres could save a billion litres a year from Australia’s 20 billion annual burn.“A billion litres is a football-field sized box – that’s a lot of fuel,” he says.“The environmental benefit is even better, saving two million tonnes of CO2 per year.“Then there’s energy security – it would be a much happier thing if the Middle East had two-thirds of the world’s reserves of brussel sprouts. But what they have is two-thirds of the world’s reserves of oil.“And most other areas where it exists are not sending us Christmas cards either.”

I have a 2008 Mazda 3 SP23 that transmits road noise into the cabin. Before I bought this car I test drove a demo with Bridgestone Potenza tyres and that also produced excessive road noise. I then inquired about the most suitable, quiet tyre and was recommended Michelin Pilot Proceda, which are fitted to my car. They made no difference and the noise still exists, especially on coarse bitumen roads. I looked under the carpet and found a reasonable amount of soundproofing foam and carpet insulation had been fitted. Can you suggest how I can reduce the cabin road noise by perhaps fitting more insulation materials under the floor carpets or something under the wheel arches?