Wire wheel 6 rigid spokes began to appear in the Olympic Games and professional racing: these have advantages in specialized applications, such as time trials, but wire-spoked wheels are used for most purposes. 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. The rest of the wheel remains approximately circular. The tension of all the spokes does not increase significantly. Instead, only the spokes directly under the hub decrease their tension. The issue of how best to describe this
Tire Wear bars (or wear indicators) are raised features located at the bottom of the tread grooves that indicate the tire has reached its wear limit. When the tread lugs are worn to the point that the wear bars connect across the lugs, the tires are fully worn and should be taken out of service. Most wear bars indicate a remaining tread depth of and are tires are deemed "worn out" when the tread is worn down to that point. The tire bead is the part of the tire that contacts the rim on the wheel. The bead is typically reinforced