Other authors conclude that the hub "hangs" from those spokes above it that exert an upward force on the hub, and that have higher tension than the spokes below the hub, which pull down on the hub. Some authors conclude from this that the hub "stands" on those spokes immediately below it that experience a reduction in tension, even though the spokes below the hub exert no upward force on the hub and can be replaced by chains without much changing the physics of the wheel. The issue of how best to describe this situation is debated. The tension of all the spokes does not increase significantly instead, only the spokes directly under the hub decrease their tension. The rest of the wheel remains approximately circular. The reaction to a radial load of a well-tensioned wire spoked wheel, such as by a rider sitting on a bicycle, is that the wheel flattens slightly near the ground contact area. Heavier riders require slightly higher air pressures. With the proper air pressure, the tire will absorb light bumps and vibrations and roll faster than a hard, inflexible tire at higher air pressures in the 120-130 psig range. With every rotation of the wheel, there is repeatedly changes in the spoke tension that can contribute to broken spokes because of fatigue failures. When the bicycle is loaded with a rider, then the spokes below the hub have less tension. Typically, each spoke is pretensioned to about 100 pounds of force, on an unloaded wheel. These have advantages in specialized applications, such as time trials, but wire-spoked wheels are used for most purposes. In the 1980s, cast wheels with 5 or 6 rigid spokes began to appear in the Olympic Games and in professional racing. It is claimed that crossed patterns have more strength and stability, and that irregular patterns are art forms and have little structural merit. Many of these patterns have been used for more than 100 years. Wheelbuilders of racing teams and in good bicycle shops build wheels to other patterns such as two-cross, one-cross, or no-cross (usually called radial). īicycle manufacturers build millions of wheels annually, using the common crossed-spoke patterns whose crossings of adjacent spokes are governed by the number of spokes in the wheel. In England, the engineer William Stanley developed the steel-wired spider wheel in 1849, an improvement over the cumbersome wooden spoked wheels then fitted to the tricycles that his employer was making. This development marked a major improvement over the older wooden wheels, both in terms of weight and comfort (the increased elasticity of the wheel helping to absorb road vibrations). They were introduced early on in the development of the bicycle, following soon after the adoption of solid rubber tires. The first commercially successful use of wired wheels was on bicycles. Their second feature was that they were easily detachable being mounted on splined false hubs.Ī process of assembling wire wheels is described as wheelbuilding. These wheels were deeply dished so that steering pivot pins might lie as near as possible to the center-line of the tires. An outer row of radial spokes gave lateral strength against cornering stresses. These wheels owed their resistance to braking and accelerative stresses to their two inner rows of tangential spokes. This was encouraged by the Rudge-Whitworth patented detachable and interchangeable wheels designed by John Pugh. They rapidly became well established in the bicycle and motor tricycle world but were not common on cars until around 1907. īicycle wheels were not strong enough for cars until the development of tangentially spoked wheels. Eugène Meyer of Paris, France was the first person to receive, in 1869, a patent for wire wheels on bicycles. The first patent for wire wheels was issued to Theodore Jones of London, England on October 11, 1826. Although Cayley first proposed wire wheels, he did not apply for a patent. They were invented by aeronautical engineer George Cayley in 1808. Wire wheels are used on most bicycles and are still used on many motorcycles. The term suspension wheel should not be confused with vehicle suspension. Although these wires are considerably stiffer than a similar diameter wire rope, they function mechanically the same as tensioned flexible wires, keeping the rim true while supporting applied loads. Wire wheels, wire-spoked wheels, tension-spoked wheels, or "suspension" wheels are wheels whose rims connect to their hubs by wire spokes. Wire wheels on a Blériot XI, which made its debut in 1909
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