Wire wheel situation is debated. 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. 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. Despite being composed of thin and relatively flexible spokes, wire wheels
Driving wheel Driving wheel On a steam locomotive, a driving wheel is a powered wheel which is driven by the locomotive's pistons (or turbine, in the case of a steam turbine locomotive). On a conventional, non-articulated locomotive, the driving wheels are all coupled together with side rods (also known as coupling rods); normally one pair is directly driven by the main rod (or connecting rod) which is connected to the end of the piston rod; power is transmitted to the others through the side rods. On diesel and electric locomotives, the driving wheels may be directly driven by the traction motors. Coupling