Bike Rims

Bike rims are essential parts of a bike. These are what hold the tires, make them a constant sturdy circle and make the main support of the wheel. Without bike rims, bikes can’t run.

The rim is an extrusion that is butted into itself to form a circle. Rims are now typically made of aluminum alloy, although until the 1980's most bicycle rims - with the exception of those used on racing bicycles - were made of steel, normally with a chrome finish. Some very high-end rims are made of carbon fiber (Like those built for race cars. Beyond the subdued bling factor, these kind of rims provide a number of dynamic benefits, including improved acceleration, braking and steering feel, the ability to allow softer dampening settings and the capability of dissipating heat more efficiently than conventional forged or cast rims.), and some very low-end rims are still made of steel. Rims have even been made of wood in the past and thermoplastic.

Rims designed for use with rim brakes provide a smooth parallel braking surface, while rims meant for use with disc brakes or hub brakes sometimes lack this surface.

The Westwood rim is designed for use with rod-actuated brakes, which press against the inside surface of the rim (or the pads pull upward against the rim). These rims cannot be used with caliper rim brakes. Westwood or the Raleigh Westrick pattern rims are required for those brakes.

Rims can either have a single-wall or double-wall cross section. Single-wall rims are usually less expensive and weaker or heavier; double-wall rims tend to be stronger and more expensive. Double-wall rims may have a deep profile either to reduce aerodynamic drag or for additional strength or rigidity, especially for wheels with fewer spokes.

Aluminum rims are reinforced with either steel washers, single eyelets, or double eyelets. A single eyelet reinforces the spoke hole much like a hollow rivet. A double eyelet is a cup that is riveted into both walls of a double-walled rim. Aluminum rims have superseded steel, because they are lighter, stronger, and more dependable.

The number of spoke holes on the rim normally matches the number of spoke holes in the hub. For a double-walled rim there are usually holes for spokes in both walls, although some factory built wheels have rim designs without holes in the wall that contacts the tire. For example Campagnolo, Shimano and Mavic brand road rims/wheels and Velocity and Mavic brand mountain bike rims.

Related Websites:
Motorcycle
Racing Tires