Tyres

The new Passat is the first car in Australia to be fitted standard with Continental's new ContiSeal tyre which seals itself in most punctures.If the tyre is punctured by a sharp object no wider than 5mm, a polymer coating on the inside of the tread will seal the hole without loss of air pressure.Volkswagen Group Australia service general manager Phil Murray this week demonstrated the tyre's ability to withstand a puncture by drilling into a non ContiSeal tyre with a 5mm drill bit, deflating the tyre. He then drilled into the ContiSeal, which stayed inflated."This is not a run-flat tyre," Murray says."Its performance is the same as the standard high-performance (Continental ContiSportContact 3)."You don't have the harshness of a run-flat tyre."And in the unlikely case you have to change a tyre there is still an alloy full-size spare wheel."Murray says the ContiSportContact 3 tyres with ContiSeal cost $550, which was $50 more than the tyres without ContiSeal.Gregor Stone, general manager of marketing for Continental importer Tyres4U, said ContiSeal was available as a 235/45R17 94W Continental ContiSportContact 3 for $648 with fitting and balancing and 235/40R18 95W Continental ContiSportContact 3 Conti Seal at $787.Stone says the ContiSeals did not weigh extra like run-flats and were not restricted to distance and speed when punctured.Continental has warned that because the motorist won't notice when their tyre has been punctured, they should regularly examine the tyre for nails or screws.The polymer coating is only on the inside of the tread, not the sidewall, however Murray said 85 per cent of punctures were in the tread area. 

One of the biggest users (and spruikers) of run-flats – BMW – is changing back to conventional tyres on some of its models.BMW will later this year switch to normal tyres on popular variants of its Mini for international markets.For Australian Minis, the standard 15-inch wheel will continue to be fitted with a conventional tyre. The larger 16-inch wheel, currently shod with run-flat rubber and selected by more than 90 percent of buyers, will also change to a conventional tyre. Run-flat rubber will now be offered as a $200 option.The 17-inch wheel will remain with run-flats.Models with conventional tyres will come with BMW's mobility pack, consisting of an air compressor and glue kit to make temporary puncture repairs.The move appears to be a cost saving measure by Mini's parent as the world-wide economic crisis hits home. Sources within Mini in Germany say BMW, which has been promoting the virtues of run-flats for years, has been disappointed that rival manufacturers Mercedes-Benz and Audi had not adopted the technology. Their added volume would have reduced the production cost of the controversial tyre for the motoring industry.Run-flats are essentially a tyre with stiffer sidewalls which allows the car to be driven if the tyre is punctured. They have been widely criticised for their harsh and unforgiving ride, especially if combined with sports suspension set ups.The lack of a spare wheel however offers substantial weight savings and wins back extra boot space.At this stage the switch back to conventional tyres has not affected BMW models, sold in Australia, most of which use run-flat tyres. 

WHENEVER I turn corners in my BA Falcon, even slowly, my tyres screech. I thought it might have been caused by under-inflated tyres or low tread, but I checked the pressure and it was fine, around 32psi, and the tread seems fine also. Is there any other reason it might happen?

AT $4 million per 30-second spot – that’s about $130,000 per second — America’s Super Bowl ad breaks are the most expensive in the world.But with an audience of around a billion – half of whom are estimated to tune in for the commercials rather than the final action of the football season — they’re also the most-watched ads for a single screening.Advertisers vie to make a splash with novel and exciting spots, and car manufacturers have been among some of the best over the years.But the 2009 Super Bowl was yet another sign of how far the industry has slumped, with few car companies showing, and none of them the US Big Three who usually dominate.Audi took advantage of the release of Transporter3 to show a Jason Statham chase scene, Toyota’s Venza linked cutting-edge design to a mundane-looking SUV, but their Killer Heat spot showed a Tundra towing a load up a flaming corkscrew ramp. (See below for more Super Bowl ads).Korea’s Hyundai had five commercials, the most entertaining one showing rival carmakers from Germany and Japan venting their anger at the Hyundai Genesis sedan being named US Car of the Year.But possibly of more interest these days was Hyundai’s `Contract’ ad, promising Americans that if they bought a new `Hunday’ and then sadly lost their income in the next year, they could return it with no impact on their credit.The only other automotive-related brand was Bridgestone tyres, which screened two commercials – an animated Mr and Mrs Potato Head, and a `moonwalk’.If the lunar one might possibly annoy viewers who don’t warm to dance music, the potato one is probably set to inflame a few feminists, with Mr Potato Head’s joy when his spouse’s mouth falls off after a sharp corner.

I HAVE never used the spare tyre in my 2000 Mitsubishi Lancer, but was wondering if it was safe to use it now that it's eight years old, or do tyres deteriorate with age?

I HAVE been frustrated by a lack of competence or poor service at various tyre service companies in my area. The result is I feel I have replaced tyres prematurely. They just want to sell tyres and never seem to be able to get the alignment right. What do you think?

I WANT to replace the run-flat tyres on my 2003 Mini Cooper with regular tyres for better ride and handling. There's no room for a spare, so I will have to rely on a foam can repairer. How reliable are they?

I'VE just replaced all four tyres on my TS Magna V6 Sedan. The tyre people told me that 36 psi is the recommended pressure for Australian roads and this would prevent the tyre edges wearing. I thought that was too high and would result in a hard ride and that not all of the tyre footprint would be in contact with the road. Four years ago these same people recommended I run 32 psi, which I've always done and have had no problems with handling, wear or performance.

Actually, it's not all that secret, but the Australian importer for Cooper Tyres has unlocked a code on every tyre, and it could be the key to getting the best grip and the best value for every tyre you buy.Most people consider new tyres a grudge purchase, replacing them only when they are bald and useless, but it does not have to be that way.The round, black hoops are never going to be as sexy or appealing as a bottle of perfume or a trip to the movies, but knowing the code can make it surprisingly interesting to see what you get for your money.And, for once, we have the US to thank. Under its consumer rules, every tyre sold must have stamped rankings for tread wear, traction and temperature. And that means almost every new tyre sold in Australia also has the rankings. But how does it work?The tread-wear ranking is a genuine reflection of how a tyre will last, compared with a “standard” tyre with a ranking of 100.Tyres are tested over a set 640km course for 11,520km, then given a comparative number.So a tyre with a 200 ranking is twice as good as the base tyre, and so on.For traction, or grip, the rankings are based on stopping power on a wet road. That's a good reflection of the softness of the rubber and its cornering power, with rankings from a basic C through to AA.For temperature, important for wear and grip, the rankings are A, B or C based on the tyre's resistance to heat and thus its ability to avoid blowouts.“Once you know these rankings, and where to find them on the tyre, you can learn a lot about the tyres on your car,” Smith says. “They also allow you to make a genuinely informed choice when you go shopping for tyres.“If you want maximum wear, go for the highest tread-wear number. If you want ultimate grip, you need an AA traction tyre.”Most people will be somewhere between the extremes, but unlocking this code is so simple. 

I AM sick and tired of the harsh ride from the run-flat tyres on my BMW 530. Can I fit ``normal'' tyres without compromising safety?