Tires evolve as technology improves, and they are subject to fashion, also. Good and bad, here are the current trends.
What are the current trends, and whether they’re good or bad
- Original equipment tires are larger and have increasingly lower profiles. This is usually an unfortunate development: many new cars have tires with an unnecessarily low profile that are poorly adapted to our roads; these low profile tires often come with high speed ratings (V for sustained running up to 240 km/h!), so they also wear out faster and are more expensive to replace. The large alloy wheels that are matched to low profile tires are expensive and vulnerable to rim damage.
- Higher performance tires are now more affordable, thanks to stiff competition in the segment and improved manufacturing techniques.
- “Run-flat” tires that remain roadworthy with little or no air pressure are becoming more common on high-end vehicles, most notoriously on the all-wheel-drive Toyota Sienna minivan, and BMW 3-series as of 2006. To a certain degree, tires that can run normally after losing air pressure represent an added safety measure in the event of a blowout at speed. However, run-flat tires are expensive, and heavier than their conventional counterparts, which increases fuel consumption. The stiff sidewalls run-flat tires require to support them when air pressure has been lost, make them hard riding and increases the force of impact transmitted to the wheels. Run-flats also tend to wear out quickly. Finally, “run-flat” does not mean you will never have to replace the tire in the event of a flat. Major damage that slices the casing will require tire replacement, and for minor damage the retailer has to go through a precise inspection procedure before repairing a flat — frequently, the tire is rejected. If the failure occurs on a driving wheel, it is often necessary to replace TWO tires, as tire wear must be relatively even on the same axle.
- Low rolling resistance tires are a welcome change from the current “fantasy era” of tire and wheel design. These tires, frequently identified as “energy saving” by their manufacturers, are reported to save 1-3% of fuel consumed; that’s equivalent to a tank or two of gasoline a year. In theory, their extra cost is repaid in fuel savings over the life of the tires.