Wire wheels

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Wire wheels, a.k.a. laced wheels, are a term primarily used in the context of motorcycles. Nearly all bicycle wheels have spokes and so the term wire construction type is assumed. A Wire Wheel has a central hub connected to the rim of the wheel via spokes made of wire. These spokes are generally quite solid and will not easily bend as would typical wire cord. Nevertheless, they mechanically function as wires under tension holding the rim true and providing strength to the wheel. The process of assembling wire wheels is called wheelbuilding.

"The fundamental fact is that the hub, and thus the vehicle borne by the wheels, in fact hangs on the spokes, which thus have to be tensioned not to break. The spokes can only be put under a pulling strain, otherwise they break."

The explanation above illustrates the common misconception that the hub of a wire-spoked wheel "hangs" from the upper spokes. A hub-spoke-rim wheel properly tensioned applies near equal force along all spokes in each direction, causing the wheel to act as one unit. Despite the common misconception that a bicycle wheel "hangs" from its upper spokes, the upper spokes show no significant change in tension. A load on the hub causes the wheel rim to flatten only very slightly against the ground as the lowermost pre-tensioned spoke shortens and compresses, losing some of its pre-tension.

For explanations, computer models, and tests confirming this odd behavior, see this analysis which shows the lower spokes of pre-tensioned bicycle wheels compressing (losing their pre-tension) as they roll under a loaded hub.

The alternative to wire wheels are solid cast (or very rarely constructed) wheels, on motorcycles know as mag wheels.