The 10 Most Revolutionary Motorcycle Designs
All motorcycles are created equal: it’s just that some are more equal than others
Throughout the history of motorcycling, there have been thousands of individual models, all of which have brought something to the table in every conceivable class, even if it is only conformity. The vast majority of designs are content to follow the general trends of the era in which they existed, while others might introduce a small innovation. There are others, however, that have had a far-reaching influence and changed motorcycling as we know it, bringing whole new concepts to motorcycle design that rivals have scrambled to copy in order to keep up. In reality, there are dozens of such models, but these are the ten that we feel stand head and shoulders above the rest.
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Along with virtually the rest of the American motorcycle industry, Harley-Davidson had relied on V-Twin engines from early in its life. These featured side valve, or ‘flathead’, cylinder heads which caused problems with heat build-up which, in turn, led to unreliability when the engines were developed to produce more power due to public demand. The next generation of Harley V-Twin engine would form the basis of the company’s engine design to the present day, at the same time becoming one of the most distinctive engines of all time. The Knucklehead had an overhead valve cylinder head, the rocker covers looking like the knuckles of a clenched fist. It gave twice the power of the flathead engine and, once teething problems had been addressed, was much more reliable. The future of Harley-Davidson was assured.
Parallel twin engines weren’t new in the 1930s: Triumph itself had released one - the 6/1 - in 1934, but it was heavy, slow and expensive, so only 600 were produced in two years. The genius of Edward Turner’s 1938 parallel twin engine was its compact dimensions - it looked exactly like a twin-port single cylinder and so wouldn’t scare off conservative buyers who were afraid of change - and its excellent power and smoothness. Even the cast iron barrel and cylinder head of early examples didn’t make it a heavy engine, and it proved to be endlessly tuneable. More importantly, it set the template for the British motorcycle for the next 40 years, one which every other manufacturer copied slavishly. The engine’s influence is still being felt today.
If the 1948 Vincent Black Shadow models garner all the headlines, the 1946 Vincent Rapide is listed here as the best example of Philip Vincent’s fertile imagination, which introduced important new concepts to motorcycling. First of all, the engine was used as a stressed member of the frame, of which there was very little, Vincent’s philosophy being: "What isn't present takes up no space, cannot bend, and weighs nothing — so eliminate the frame tubes!” A box-section upper frame member was bolted across the top of the engine which served as the oil tank and to which the front headstock and rear suspension were attached, the latter being a cantilevered triangular swing-arm with twin telescopic shock absorbers, the pivot bolting to the rear of the engine/gearbox casing. Despite this innovation, Vincent stuck with girder front forks, believing them superior to the telescopic forks of the time.
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Immediately after the Second World War, aircraft manufacturer Piaggio was effectively banned from producing aircraft and desperately needed something to manufacture in order to keep the company afloat. Looking at the post-war world, Enrico Piaggio identified the need for a modern and affordable mode of transport for the masses. The eventual product was called the Vespa, because with its bulbous tail and slim ‘waist’ it looked like a wasp and Vespa is Italian for wasp! The two-stroke engine was mounted in unit with the rear wheel and swing arm and the bodywork kept it out of sight as well as protecting the rider. The design was every bit as influential as the later Honda Super Cub and became not only a design icon but a symbol of Italian design flair.
What would motorcycling have looked like without this diminutive and ground-breaking design? Soichiro Honda and business partner Takeo Fujisawa conceived a motorcycle that needed to be light, simple, easy to operate, clean, safe, reliable and could be worked on with the simplest of tool kits, such as many rural owners would likely possess. The revolutionary plastic bodywork hid the mechanical bits and kept the rider protected from road dirt, the gearbox was semi-automatic and easy to learn, the wheels were larger than other scooters to be suitable for bad roads. Thanks to an advertising campaign in the U.S. - ‘You meet the nicest people on a Honda’ - the Super Cub even managed to change people’s perception of motorcycles and motorcycling from something ridden by outlaw gang members to an acceptable means of transport for the family man.
Throughout the 1960s, the Japanese motorcycle industry had been growing at an incredible rate but still the British and Americans underestimated the threat, believing that buyers would start on the small-displacement Japanese models before graduating to the larger motorcycles they built. Then, in 1969, Honda revealed the CB750 and the motorcycling world would never be the same again. In the face of seriously out-of-date designs by the British and Americans, the Honda was from the future: transverse inline four-cylinder engine, which was powerful, smooth, reliable and leak-free, had electric start and a front disc brake. It was fast, well-made and was another nail in the coffin of the British motorcycle industry which was, to be fair, on its last legs anyway, even without the CB750 and later Kawasaki Z1.
Ducati started building motorcycle after the Second World War, much like Piaggio and concentrated on small-displacement, single cylinder motorcycles, albeit with some interesting engineering, such as desmodromic valve actuation. With the arrival of the Honda CB750 and Triumph Trident 750, the motorcycling world was changing so Ducati engineer Fabio Taglioni designed a 90° V-Twin, with a displacement of 750cc. The first bike this appeared in was the 1971 750 GT, which can rightly be called the father of the modern Ducati sports bike, even though it wasn’t necessarily a sports bike. That honor fell to the 750 Supersport, introduced after Ducati’s sensational win in the Imola 200-mile race in 1972. But, as the beginning of a sporting bike dynasty, the 750 GT has the best claim.
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In the late 1970s, BMW’s reputation was suffering a little from being too staid and too expensive. Then, BMW engineers looked at a Range Rover in the car park and asked why they couldn’t make a bike in the same mold - comfortable and fast with off-road capability. So, the R80 G/S (Gelande/Strässe, or ‘Off-road/Road) was born. Powered by a 797cc boxer twin engine and with long-travel suspension and a 21-inch front wheel, the G/S was a new concept in motorcycling and one that caught the attention of the motorcycling public following a quartet of victories in the Paris Dakar rally. Not only is the GS still with us, in the form of the R1250 GS, but it inspired every single manufacturer to follow suit and the adventure bike craze started.
Even though the sporting Japanese motorcycle had existed for several years, it took the Kawasaki GPz900R to solidify the layout of what would become the modern superbike concept. On its launch in 1983, the GPz900R was a leap forward, with a powerful water-cooled inline four-cylinder engine, a fully integrated fairing, monoshock rear suspension and a spine frame, at a time when most Japanese sports bikes had a naked, twin-shock, tubular cradle frame. It was a brilliant performer, both as an all-round sports tourer and a full-on sports bike and would remain in production for an unprecedented 19 years. In 1984, the GPx900R came first and second in the Isle of Man Production TT race, confirming its credentials.
If Kawasaki invented the modern sports bike, then Honda developed the concept into what we accept today as being the definitive sports bike design. Previously, the Japanese manufacturers had chased speed with ever more power, at the expense of weight and agility. The CBR900RR Fireblade changed all that: the engine might have been less powerful than the likes of the Suzuki GS-R1100 (124 horsepower against the Suzuki’s 143) but the bike overall was a lot lighter and much more compact, giving incredibly nimble handling and being far more manageable and, therefore, fun. It immediately made every other sports bike look dated and overweight, and it bought Honda a six-year head-start over the competition.
Harry has been writing and talking about motorcycles for 15 years, although he's been riding them for 45 years! After a long career in music, he turned his hand to writing and television work, concentrating on his passion for all things petrol-powered. Harry has written for all major publications in South Africa, both print and digital and produced and presented his own TV show called, imaginatively, The Bike Show, for seven years. He held the position of editor of South Africa's largest circulation motorcycling magazine before devoting his time to freelance writing on motoring and motorcycling. Born and raised in England, he has lived in South Africa with his family since 2002. Harry has owned examples of Triumph, Norton, BSA, MV Agusta, Honda, BMW, Ducati, Harley Davidson, Kawasaki and Moto Morini motorcycles. He regrets selling all of them.