The foot platform
A pedal is the point where the rider’s body meets the machine. It looks like a simple part, but it must carry a rider’s full weight, allow the foot to push and pull, and spin freely on the crank. This article focuses on the platform itself and how the foot is held to it. The pedal cranks that carry it have a history of their own.
Early pedals
On the first pedal velocipedes, the pedals were simple wooden or metal footrests attached to the cranks of the front wheel. Because the cranks turned with the wheel, riders had to learn to keep their feet in place as the pedals went round.
The standard arrangement soon became a platform that turns freely on a spindle at the end of the crank, so the foot can stay level while the crank rotates. That layout is still the basis of nearly every pedal today.
The rubber block pedal
For many years the standard pedal on ordinary bicycles was the rubber block pedal. It had a metal frame holding two or more blocks of vulcanized rubber that gave grip to the sole of a shoe. The rubber also reduced vibration and was comfortable for shoes of any type. Rubber block pedals were common on roadsters and utility bicycles, and the style remains familiar on many children’s bicycles and city models.
Rubber blocks were gradually replaced by other materials, but the basic idea of a flat platform with a gripping surface stayed. Modern platform pedals often use plastic or metal with studs or pins for grip.
The rat-trap pedal
Another classic was the rat-trap pedal, sometimes called a bear-trap pedal. It had two steel plates with serrated edges, giving a toothed surface that could grip a shoe from both sides. Rat-trap pedals were light and cheap, and they were used on sports and touring bicycles for decades. They were not particularly comfortable on thin-soled shoes, but they were durable and easy to repair.
Toe clips and straps
Racing riders wanted to keep their feet firmly in place and to apply force on the upstroke as well as the downstroke. A solution that emerged around the early twentieth century was the toe clip: a metal or plastic cage fixed to the front of the pedal, with a leather strap across the top of the foot. The shoe slid into the cage, the strap was tightened and the foot was held in position.
Toe clips gave riders more control over their pedaling, but they had drawbacks. The strap had to be loosened to remove the foot, and a rider who stopped suddenly could find it hard to get free. Riders learned to flip the pedal with a toe and slide the foot in, a technique that took practice. Even so, toe clips were standard on racing and sports bicycles for much of the twentieth century. Shoes with slotted soles, called cleats, were used with the pedal to improve the connection.
Clipless pedals
The name “clipless” can be confusing. It refers to the absence of the toe clip, not of any clip-like mechanism. A clipless pedal has a spring-loaded binding, similar to that of a ski, that engages a small cleat on the sole of a special shoe. The rider steps in, and the foot is held; a sideways twist of the heel releases it.
Early experiments with this idea appeared in the 1960s and 1970s. A pedal introduced by an Italian maker in the early 1970s is often mentioned as an early attempt. The system was popularized in the 1980s by a French company whose pedals were used by the Tour de France winner Bernard Hinault in 1985. After that, clipless pedals spread across racing. In 1990, a mountain-bike-oriented design with a recessed cleat made it possible to walk in the shoes, and that development helped move clipless pedals beyond road racing.
Why feet changed riding
Attaching the foot has some effects on riding technique. It lets the rider use a more circular pedal stroke, with a mix of pushing and pulling, and it keeps the foot from slipping on rough ground or in the rain. Riders who prefer freedom to put a foot down quickly may choose a flat platform instead, and in some off-road riding the flat pedal has returned to favor, now with studs and shaped surfaces. These are matters of preference and discipline and not rules.
Materials and bearings
Pedal materials followed the general trend of the bicycle. Early pedals were wood, iron and brass. Steel and aluminum alloys, with improvements in aluminum smelting, made lighter forms possible. Better bearings allowed pedals to turn smoothly, and sealed designs resisted dirt. Replaceable parts such as cleats and pins reflected a growing attention to maintenance.
On electric bicycles, some pedals include sensors that detect the rider’s effort, an example of how an old part continues to take on new roles.