The Evolution of the MX Bike Through Landmark Examples
Motocross Racers: 30 Years of Legendary Dirt Bikes (Motorbooks, 2003)
By Ray Ryan, Photographs by Bill Forsyth and Jeremy Holland
Review by Jeffrey Morseburg
Motocross Racers is an Australian production that has been published for the American market by Motorbooks, the prolific Minnesota-based motorsports label. It’s a beautifully produced book that serves as both a picture book as well as a guide to the constant evolution of the post-war motocross machine. The author Ray Ryan and photographers Bill Forsyth and Jeremy Holland are all active in the vintage motocross movement and work together on the magazine VMX.
For the uninitiated, motocross is a form of off-road motorcycle competition where the riders race on unpaved circuits with steep hills, descents, straights and corners. Originally these circuits were natural paths through British and European parks, but eventually more challenging, purpose-built courses became the norm. Because the bike has to be muscled around the circuit, with the arms lifting the handlebars and the legs absorbing the shock of repeated landings, it is a deceptively athletic event, requiring good upper and lower body strength as well as endurance. Crashes are also part of the sport, but the most common result of these are muscle strains, bruising and broken bones rather than serious injury, for modern safety gear has made the sport much safer.
Motocross started in Great Britain in 1924, where the sport was originally called “scrambles,” and it gradually became popular in Europe. By 1952 a European Championship was organized, and in 1957 that series became a World Championship. Immigrants from England and the continent brought the sport to Australia and New Zealand, where it became popular after World War II.
In the United States, where flat-track racing on oval courses had long been popular, scrambles on closed circuits only had a small following until the 1960s. By 1966 and 1967, when European riders like Torsten Hallman and Oriel Puig Bulto began to demonstrate their abilities on the relatively easy American courses, some American riders began to specialize in motocross. The Trans-AMA, a U.S. series with the top international riders, began in 1970 and helped to fix motocross in the American consciousness and start an off-road motorcycle boom in the States. In the early years of the Trans-AMA, European riders were dominant, but in 1978, the last year of the series, Bob “Hurricane” Hannah was the victor. By the 1980s, U.S. motocross had come of age and American riders began a 13-year winning streak at the Motocross de Nations, the “Olympics of Motocross.”
In any sport that pits one man and machine against another, competitors will strive to improve their machines in order to gain an edge against their rivals. In the 1940s motocross bikes were usually just street bikes that were stripped of their lights and other road equipment, but gradually these lightly modified machines – which did not cope well with the bumps and jumps of the rough circuits – gave way to stronger, lighter custom frames made of light-but-strong chrome-moly tubing for those who were factory-sponsored or who could afford them. The best riders rode on hand-built factory specials, the production of which was only affordable for factories which sold thousands of motorcycles. Some riders began fabricating “bitsa” bikes (for a bit of this and a bit of that), which gradually led to the mass-production of specialized motocross bikes from major manufacturers who tested components and concepts on their prototype bikes known as “works bikes.”
The Legendary Motocross Beauty, the Rickman-Metisse
During the evolution of the sport of motocross from the 1950s through the 1970s, the top manufacturers in the early years were Belgian (FN or Fabrique National) and British (BSA, Norton, Matchless), then Czech (CZ), Swedish (Lito, Husqvarna), and German (Maico). In the 1960s and ‘70s, the tremendous engineering talent and volume of the Japanese began to tell, and Suzuki, Yamaha and Honda won one world title after another while also dominating the huge new sport of American motocross. By the late 1970s, the four large Japanese factories were selling more than a million motocross bikes a year.
Stadium motocross, known as “Supercross,” began in the United States and soon spread to Europe. Drawing audiences of 70,000 or more, Supercross events were incredibly successful and immediately outdrew the crowds on outdoor circuits. Its tremendous popularity was a lifeline for outdoor motocross in the United States, where the circuits were usually far away from population centers. Because the spectacular supercross events were fast-paced, colorful and easy to film, they made motocross into a trendy sport and top riders like Bob Hannah and Jeremy McGrath became household names.
Engine technology also changed dramatically over the decades. In the 1950s, heavier, more complex four-stroke engines (where the spark plug fires every four times the engine’s piston rotates) were dominant in motocross, but by the 1960s, two-stroke technology had evolved to the point where their greater power and lighter weight made them the mount of choice. However, in recent years things have come full circle as the two-stroke engine, which produces considerably more emissions, has come to be seen as an evolutionary dead-end and has been replaced by new, powerful, lightweight 4-stroke designs.
All this evolution is on display in Motocross Racers, which starts out with four-stroke motocross bikes. First there is an exotic factory-built Les Archer Manx-Norton special, then a lengthy section on the legendary Rickman-Metisse, the English frame kits that made factory “works bike” technology available to the every rider who could afford them in the 1960s. This is followed by an Eric Cheney-built custom bike with the famous BSA Gold Star engine, then a BSA 441 “Victor” Grand Prix bike. The transition to two-stroke technology begins with the unbreakable Czech CZ, a classic Swedish Husqvarna 250 motocrosser that was ridden by the World Champion Torsten Hallman, followed by a 1967 Suzuki TM 250, the Japanese company’s first real stab at what was becoming a growing market. The last bike of the 1960s featured in the book is the small Hodaka Super Rat, a 100cc motocross bike which got thousands of American boys started in the sport.
A Beautifully Photographed Book
Motocross Racers includes the ground-breaking 1973 Honda Elsinore, a Bultaco Pursang Mk 7, then World Champion Joel Robert’s featherweight “works” Suzuki RH250, the rare British four-stroke CCM special, a bike that couldn’t make the grade because of its low power-to-weight ratio, the revolutionary 1974 Yamaha460YB, that began the single rear shock revolution, another Husqvarna, one of the CZ company’s last competitive bikes, a rare Puch factory motocrosser, then there is a steady stream of long-travel 1980s Japanese mounts – Hondas, Yamahas, Kawasakis and Suzukis – only broken up by a Husqvarna and a Maico, as the Japanese had become dominant in racing as well as technological development. The march of bikes concludes with some 1990s Yamahas and Hondas, the development of the monocoque-framed motocross bike and finally, with the Austrian KTM company’s latest model at press-time, the 2003, KTM525SX, a light, powerful 4-stroke bike with a wonderfully broad powerband.
Rather than a steady narrative, author Ray Ryan has chosen to cover each of his motorcycles in its own chapter, describing its unique strengths and weaknesses and the part it played in the evolution of the motocross bike. His writing is clear and concise, and the text is not overly technical, but those new to motocross may want to look some things up on the Internet. There isn’t a lot of information on the riders of each era, but the focus here is on the technical development, rather than the personalities involved. The images are outstanding, with virtually all of the posed in suitable outdoor locations. It would have been nice to see more period action shots, but permission and photo gathering may have been an issue, especially for authors working from Australia. In only 158 pages of text, Ryan covers a lot of bumpy ground. I can’t think of a better introduction to the mechanical side of motocross history than Motocross Racers: 30 Years of Legendary Dirt Bikes.
Rating: 5 Stars
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