Rim Blow $37. A rubber pad encasing wires was mounted around the entire inner surface of the steering wheel rim. Rather than pressing a suspended horn ring, a center horn pad, or switches on the spokes, to make the electrical contact, the inside of the rim could be pressed anywhere on its circumference. Applying pressure to soft rubber inner rim of the steering wheel, a driver could activate the car's horn without moving their hands from the wheel rims. Technical issues, such as hardening (difficult to activate) and shrinking (causing the horn to sound without activation) of the rubber, and a lack
Bicycle wheel of center. "Vertical truing" refers to adjustments of local deviations (known as hop) of the radius, the distance from the rim to the center of the hub. "Dish" refers to the left-right centering of the plane of the rim between the lock nuts on the outside ends of the axle. This plane is itself determined as an average of local deviations in the lateral truing. For most rim-brake bicycles, the dish will be symmetrical on the front wheel. However, on the rear wheel, because most bicycles accommodate a rear sprocket (or group of them), the dishing will often be asymmetrical: