Where would you be without wheels?

By T. Uncle

Not all the star attractions of the Tokyo motor show in 1993 were cars.

Tucked away on one of the trade stands, far removed from the main hall, was a piece of outrageous technology that was a portent of things to come.

This was the mother of all alloy wheels. No less than 18- inches in radius, it eclipsed any of the oversized, stylish creations seen on the new products displayed in the main hall.

Wrapped around it was something described as a tire, but in reality looking more like a thin, stretched band of rubber intended more to keep the gargantuan wheel's massive rims from scraping the ground than to cushion road shocks.

The intriguing thing about this outlandish creation was that its intended function was to perform as a more-or-less regular road wheel on a more-or-less regular car.

It was, then, the most extreme expression of the way automotive wheel design was headed.

From the small-is-better theories of the 1960s and 1970s, influenced by such cars as Alex Issigonis' Morris Mini with its 10-inch wheels, car wheels had been growing and growing in size, so that by the 1990s, the 15-inch items that were once considered oversize were the rule rather than the exception on regular, full-size road cars.

That was 1993. In 1997, the large-diameter wheel has become accepted hardware on any car with a legitimate performance bent, and the 18-inch wheel doesn't seem that outrageous anymore.

Even the new-age VW Beetle that is expected to hit the world market in the next two years comes as standard with either 15- inch or 16-inch wheels. In this case, purely for aesthetic reasons, linking the latest front-drive incarnation of the world's most familiar automotive shape with the original design.

The fact is that the road wheels are probably the most powerful visual statement that can be made with a motorcar before taking the next step and modifying the bodywork or resetting the suspension.

A set of dramatic but compatible alloy wheels will transform the appearance of any car.

In fact, there is probably some truth in the theory that carmakers deliberately hold back on wheel design when a new model is introduced to leave some scope for the accessory and aftermarket business to sell their image-enhancing products.

One only needs to look at how quickly the aftermarket comes up with wheel and body packages for just about any new car to find evidence that the theory may not be far from the truth.

And the truth is that, today, the alloy wheel is essentially a cosmetic item.

A long way from the days when the first alloy wheels made their appearance on race cars as strong, lightweight alternatives to steel rolling stock, today's road-going alloys generally have nothing to offer in weight advantages over the regular factory items.

The only real gain is that, in order to provide the race-bred, substantial look, the "serious" alloy wheel will assist road holding by allowing the car a bigger "footprint" via its wide- section, low-profile tires.

A well designed wheel will have other advantages other than its looks, of course.

If the design is well executed, the spokes will be fashioned in a way that allows improved ventilation of the brakes while also providing improved strength.

And there is the fact that although aftermarket wheels are generally built with strength and durability in mind, some are better made than others.

A cheap aftermarket alloy wheel will often show its lack of mettle (or the use of poor-quality metal!) through being impossible to balance, or may even display metal porosity that, in addition to compromising strength, will also make it difficult to seal the tire against the rim, or maintain air pressure if a tubeless tire is used.

Poorly made wheels also tend to look that way when examined from close range: the finishing-off is clearly not to the same level as a wheel from a recognized wheelmaker.

There are other things to bear in mind when changing steel wheels for a neat looking set of alloys.

One thing most buyers who go from regular tires to low-profile designs first notice is a loss of ride comfort that is often directly proportionate to any gains achieved in roadholding.

Another phenomenon is the kickback, described as bump-steer, that is a by-product of using a wider rim with a great offset than standard.

Put simply, this comes about because the wheel sits out further from the point where it pivots as it steers, thus increasing the "leverage" effect of any road bump or irregularity.

This is felt by a disconcerting "tugging" the steering wheel on bumpy roads, especially when the brakes are being applied.

The bottom line is that while a set of oversized alloy wheels will almost always dramatically lift the appearance of the car, there's every chance that the car will no longer be particularly pleasant to drive on anything but an ultra-smooth road.

The advice of a wheel and suspension expert is well worth seeking before making a big financial commitment.