The bad news is, new technology is altering Homo sapiens' evolution such that, in one generation, few of us will know how to change a tire, a basic skill man has been performing for millions of years. Still, the technology shows progress in our species. The spare tire is disappearing, and standard equipment nowadays is more likely to be a canister of tire sealant—or a cellphone to call for roadside repair. Unless, of course, you have run-flats.A cross section of Bridgestone's run-flat tire shows how steel and rubber combine to keep you rolling. For 50 miles, anyway. (A) Molded fins on the outer edge draw heat from the tire so it lasts longer. (B) Reinforced sidewalls keep the deflated tire from collapsing.A run-flat tire will run, uh, flat for 50 miles at 50 mph, enough to get you to a repair shop. It's built with stiff sidewalls so that even when deflated it can support the car. Though the technology has been around since the 1980s, the Bridgestone Drive Guard is the first to really go mainstream—and at a price that's comparable to an equivalent touring-grade tire ($100 to $200).

Can I put them on my old Honda Accord? Run-flats should be installed only on cars that have a tire- pressure monitoring system (TPMS) that alerts the driver to a pressure decrease. That includes most new passenger cars since 2008, though the system can be retrofit on older cars.Is it as good as a normal tire?Earlier generations of run-flats were too heavy, too noisy, and not durable. But the DriveGuard has a taller profile that yields a better ride. We maneuvered a Toyota Camry equipped with them through a tricky course with a deflated front-left tire. One tight corner would have pulled a flat standard tire off the rim, but the DriveGuard stayed put. Well, kind of: Bridge stone had painted a mark on the tire, so you could see that the tire had slipped a little around the wheel rim, something the engineers said is acceptable. It pulled a little under braking, and there was noticeable noise, but not the flapflapflap of a typical flat. On a wet course we found traction on both DriveGuard and Bridge stone's traditional Turanza to be the same.

If it works so great, how will I know I have a flat?The tire-pressure warning light on the dash glows.What happens if I just keep going?In a deflated run-flat tire the internal flexing generates lots of heat, which destroys both the rubber and the underlying steel-and-fabric structure. DriveGuards feature something called cooling fins molded into the sidewalls to disperse heat. Still, they're pretty much toast after 50 miles.part worn tyres glasgow scotland streetSo, I can't fix it?tire stores lindsay ontarioProbably not, unless it's just a puncture in the tread and you caught it early. car tyres in gwentIn most cases you'll need a new tire.part worn tyres goodyearDoes this mean I don't need a spare?tires and rims for jeep commander

Well, neither run-flats nor sealant-and-compressor kits can fix a bent rim. Plus, run-flats typically have a lower profile, so they provide even less rim protection. If you break a rim, you'll miss having a fifth wheel, so if you're buying a new car and a spare is available as an option, get it. And if you see a teenager, show him how to change a tire. For the good of the species.Spare the run-flat tires, spoil the ride on Lexus SC430used tire shop jefferson ga Run-flat Tires Getting A Bigger Toehold Spare tire: safety net or space waster? Hit The Road, Jack Spare the run-flat tires, spoil the ride on Lexus SC430 Autos BMW is offering Goodyear Eagle run-flat tires... Don't let price be an object in replacing run-flat Out with Z3, in with Z4 Retort to call for tort reform Spare Tires May Be Headed For Museum Display Cases Tight trunk dictating Lexus tires

Run-flat Could Save You Spare Under pressure to introduce tire monitors ConnectLike us on FacebookFollow us on TwitterAs automakers increasingly ditch the doughnut in favor of run-flat tires and emergency inflator kits, AAA is making a plea to spare the spare. The roadside-services provider says it has seen no decline the past five years in the more than 4 million flat-tire assistance calls it receives annually, and despite newfangled substitutions there's no substitute for a trusty ol' spare tire in the trunk. Related: Getting the Right Tire "Tire inflator kits, a high-cost alternative for consumers, have replaced the spare tire in millions of vehicles over the last 10 model years and, due to their limited functionality, cannot provide even a temporary fix for many common tire-related problems," AAA stated, estimating that 30 million drivers could be left stranded at the roadside as a result. Despite what AAA calls "minimal savings in fuel consumption" due to weight reduction, spare-tire alternatives have expanded from being found in just 5 percent of vehicles to more than a third between 2006 and 2015 — and at a cost.

Kits can cost as much as 10 times more than a tire patch and need replacement in as little as four years, AAA said. Moreover, AAA's testing of common inflator kits revealed that they were effective only when the tire was punctured in the tread surface with the object still stuck in the tire — and not useful in the case of sidewall damage or a blowout. "Automakers are facing increasingly stringent fuel economy standards, and the spare tire has become a casualty in an effort to reduce weight and boost miles per gallon," said John Nielsen, AAA's managing director of automotive engineering and repair, in a statement. "Advances in automotive engineering allow for weight to be reduced in ways that don't leave motorists stranded at the roadside." BMW is well known for its use of run-flat tires, which come on most of the automaker's vehicles, with some exceptions. All M-badged BMWs come with standard tires and an inflator kit except for the X5 M and X6 M, which come with a space-saver spare tire;

M performance models such as the M235i and X4 M40i can get run-flats as a no-cost option. A space-saver spare is also available as an option on the X1, X5 and X6 SUVs, as well as on the 7 Series sedan. The lone BMW model that allows customers to get standard tires and a spare in place of run-flats as a no-cost option is the X1. Hector Arellano-Belloc, a spokesman for BMW, said the automaker's customers "enjoy the advantages" of run-flat tires. One such perk, of course, is not having to get out of the car and change a flat at the roadside, and instead being able to drive to the nearest convenient repair shop. An unintended consequence of the gradual disappearance of the conventional spare tire has been to make it the eight-track tape deck of emergency automotive equipment. According to AAA figures, compared with drivers ages 35 to 58 — 90 percent of whom know how to change a tire — less than 20 percent of 18- to 34-year-olds possess this once-basic skill. These AAA statistics may be face-palm inducing for old-school tire changers who still value this skill.