Bicycle pedal

The bicycle pedal is the part of a bicycle that the rider pushes with their foot to propel the bicycle. It provides the connection between the cyclist's foot or shoe and the crank allowing the leg to turn the bottom bracket spindle and propel the bicycle's wheels. Pedals usually consist of a spindle that threads into the end of the crank and a body, on which the foot rests or is attached, that is free to rotate on bearings with respect to the spindle.

Pedals were initially attached to cranks connecting directly to the driven (usually front) wheel. The safety bicycle, as it is known today, came into being when the pedals were attached to a crank driving a sprocket that transmitted power to the driven wheel by means of a roller chain.

Just as bicycles come in many varieties, there are different types of pedals to support different types of cycling.

Traditionally, platform pedals were pedals with a relatively large flat area for the foot to rest on, in contrast to the quill pedal which had very little surface area.

One form of the platform pedal had a large flat top area and flat bottom for use with toe clips and toe straps. They were designed for greater comfort when using shoes with less than rigid soles. They typically had a smaller cutaway underside giving greater cornering clearance, which was often needed for track cycling. They were often marketed as being more aerodynamic than conventional quill pedals.

Attaching the shoes to the pedals gives the user more control over the pedal movements. There are two methods for attaching a cyclist's shoes to their pedals: toe clips, a basket-and-strap device which hold the foot in place; and so-called clipless pedals, where specialized shoes with built-in bindings attach to compatible pedals.

In mountain biking (MTB) and BMX, platform pedals typically refer to any flat pedal without a cage. BMX riders typically use plastic pedals made of nylon, polycarbonate, or carbon reinforced plastic, although aluminum alloy, and magnesium are not uncommon pedal body materials. Mountain bikers tend to use aluminum or magnesium because of the necessary use of metal studs to offer grip while the pedals are wet, muddy and slippery. BMX'ers tend to prefer platforms to cage pedals because they offer more support and grip for flexible "skate" shoes by using short metal studs. Cage pedals are more popular in the low end mountain bike range. In general, cage pedals are uncommon in all types of biking, although there is a niche market within mountain biking.

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Wikipedia