How Stuff Works

Knock-off wire wheels

Unless you are reading this in the 23rd century and hover or maglev cars are commonplace, wheels are essential equipment if you want to get anywhere fast – or slow.

Wheels do have an inherent problem, though, and that is that they are ‘dead’ weights. What I mean by that is that they are unsprung weights, rolling and bouncing down the road, and the more unsprung weight a vehicle contains, the harder it is to control.

Imagine driving a Land Rover with no springs and solidly mounted engine and gearbox, with a wooden block for a seat. Your eyeballs and internals would be vibrating so violently that progress at anything but a snail’s pace would be excruciating, not to mention the vehicle bouncing all over the place under the influence of road surface imperfections.

Now, perhaps the above scenario is a tad far-fetched, but keeping the unsprung weight of a car to a minimum is desirable and that’s where the wire wheel comes in.

Early cars often featured spoked wheels made from wire or wood. Had solid wooden wheels been used on such vehicles, the gyroscopic effect would have been phenomenal, such that turning corners could have been interesting. Besides, a lot of early cars were built by bicycle manufacturers and so, naturally, featured bicyclelike wheels, constructed using a central hub with spokes radiating from it, out to a relatively lightweight rim, eliminating most of the material otherwise needed for a solid item.

Wire wheels were, however, timeconsuming and expensive to make. Gradually, as manufacturing methods improved, it became possible – and far less expensive – to produce complete, lightweight pressed-steel wheel centres, with rims welded onto them. These weren’t necessarily as light as wire wheels, but light enough. Besides, wire wheels started to be offered as an option, but the appeal for what could have been looked upon as ‘old-fashioned tech’, came from a different direction.

Race and competition cars had long used wire wheels as an aid to getting cooling air to hard-pressed brake drums, thus keeping brakes operable even under heavy use, when excessive heat reduced the coefficient of friction between brake drum and brake-shoe lining material.

The aforementioned lighter weight was, of course, a useful addition to the package, but it was the method of attachment of the wheel that became a huge part of the attraction.

Knock-on, knock-off, RudgeWhitworth-type hubs, with single central wheel nuts, featuring ‘ears’ or ‘wings’ – used for tightening or loosening with the judicious use of a soft-faced hammer – were a commonplace feature on competition cars, where the speed of wheel changes could mean the difference between winning or losing.

Such wheels, fitted to their special splined hub adapters, were often fitted as standard to sports cars, but could – and did – add rakish flare to otherwise humdrum everyday cars.

Pressed steel wheels with these fixings were also produced and both remained commonplace options on new cars up until the early 1970s, when lightweight and modern alloy wheels stole the show.

Today, wire wheels remain a popular modification on periodcorrect classic cars, with body-colour painted versions being particularly in vogue, although silver painted and chrome-plated remain evergreen choices among afficionados.