BMX

BMX, cycle sport in which participants ride bicycles that are specialized for performance on dirt tracks built with features such as rollers, jumps, and banked curves or that are specialized for stunt riding. BMX includes recreational and off-road riding as well as competitive BMX racing and BMX freestyle. BMX is represented in international events, including the Olympic Games and the X Games.

History

The origins of BMX can be traced to the mid-1960s in southern California, where young riders built dirt courses on vacant lots and raced around them. The emergence of the sport was facilitated in part by the development of relatively small, easily maneuvered and customized bicycles, particularly the Schwinn Sting-Ray. Participants and enthusiasts referred to the sport variously as pedal cross, BX, and pedal power. The first official BMX race took place on July 10, 1969, having been organized by Ron Mackler, the superintendent at Palms Park in Santa Monica. Earlier that year a group of kids who were riding on the dirt trails at Palms Park persuaded Mackler to build a motocross-like track at the park. Mackler organized races there from 1969 through 1984.

Interest in BMX grew significantly following the release in 1971 of the motorcycle racing documentary film On Any Sunday. The movie’s opening credits feature a group of kids racing their bikes on dirt trails, catching air over jumps, and popping wheelies while imitating the sounds of motocross bikes. The film, which featured American actor Steve McQueen and was nominated for an Academy Award for best documentary feature in 1972, is credited with opening the doors for the sport across the United States.

In 1973, with the increasing popularity of BMX, motocross promoter Ernie Alexander founded the first national sanctioning body for the sport, the National Bicycle Association (NBA). In 1974 George Esser, who led the National Motorcycle League, founded the National Bicycle League (NBL). In January that year he organized a BMX race at Miami-Hollywood Speedway Park in Florida. The first “unofficial” national BMX championship was held in September 1974 at the Los Angeles Memorial Coliseum. It was a promotional event, named the Yamaha Bicycle Gold Cup finals, after track operator Scot Breithaupt persuaded the company to invest in the race to promote its new line of bicycles. More than 5,000 spectators attended the event. In 1975 the NBA hosted what is widely regarded as the first official national BMX race, in Phoenix. Two years later BMX promoter Gene Roden and Merl Mennenga, a track operator, formed the American Bicycle Association (ABA) in Arizona. In 1981 the NBA ceased to exist, and finally in 2011 the two remaining organizations—the ABA and NBL—merged to operate under a single sanctioning body, USA BMX.

BMX racing

The tracks in BMX racing vary substantially. For example, some tracks are as short as 275 meters (about 900 feet) while others can reach lengths of almost 400 meters (about 1,300 feet), and tracks can have different layouts and obstacle sizes. However, on all tracks, regardless of length and layout, racers begin at an eight-lane, 7.3-meter- (24-foot-) wide starting gate at the top of a starting hill, which allows riders to accelerate quickly upon descent. Obstacles on the track can include double jumps (two hills spaced apart to give riders the option of jumping from the first to the second or jumping each individually), step-up jumps (a short hill followed immediately by a taller hill), step-down jumps (a tall hill followed immediately by a smaller hill), berm turns (180-degree, 90-degree, or long sweeping turns), rollers (small hills—often two to more than four—in succession), rhythm sections (a combination of jumps of varying sizes), and table tops (jumps with a plateau as their peak).

Bikes for BMX racing usually have 51-cm (20-inch) wheels with knobby tires and are equipped with upright handlebars with crossbars, a lightweight saddle, a single-speed crank, and platform pedals. The frame of the bike typically is made of either aluminum or chromoly (chromium-molybdenum) steel. The goal generally is to make the bike as lightweight as possible without sacrificing its sturdiness, handling, or other performance capabilities. Rider size and ability, as well as track conditions, greatly influence bike handling, and thus many BMX racing bikes are highly customized.

BMX freestyle

BMX freestyle slowly emerged from the mid-1970s, when riders experimented with their bikes on obstacles and ramps intended for skateboarding. Riders increasingly came up with tricks that could be performed in midair, such as flips, and eventually competitions were introduced. BMX freestyle competitions typically are held at purpose-built skate parks, on wood or concrete surfaces that incorporate a variety of obstacles. The competitions involve timed runs, wherein riders perform a sequence of tricks, including front- and backflips, 360s to 1080s (one to three full turns), tailwhips (frame spins), barspins, and any combination thereof, on the obstacles. Obstacles include jump boxes (used to jump from one side to the other), quarter pipes (ramps to turn on while performing tricks), spines (two back-to-back quarter pipes with a large platform on top), hitching posts (elevated bars on top of a ramp), and rails of different heights, shapes, and forms.

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Freestyle bikes need to be sturdier than bikes used for racing, and thus the frames are often made of reinforced high-tensile steel. The wheels are either mag-style, being made with sturdy nylon, or 48-spoke heavy duty; the tires are wide with smooth tread. Freestyle bikes have both rear and front brakes, the front brake cable being routed through a detangler to allow for barspins. The bikes also are equipped with stunt pegs to allow riders to perform grinds (sliding part of the bike along an obstacle).

BMX worldwide

BMX racing was introduced as an Olympic sport at the Beijing 2008 Olympic Games. BMX freestyle made its Olympic debut at the Tokyo 2020 Olympic Games (held in 2021 because of the COVID-19 pandemic). Today numerous countries have BMX organizations, and racing and freestyle competitions are hosted worldwide. Major events include the British BMX Championships, the European Cycling Union (Union Européenne de Cyclisme; UEC) European Championships, the Asian BMX Championships, the Pan American Games, and the International Cycling Union (Union Cycliste Internationale; UCI) BMX Racing World Cup.