of status, a cultural icon for individualism, a prop in Hollywood B-movies. The motorcycle also became a recreational machine for sport and leisure, a vehicle for carefree youth, not essential transportation for the mature family man or woman, and the Japanese were able to produce modern designs more quickly, more cheaply, and of better quality than their competitors. Their motorbikes were more stylish and more reliable, so the British manufacturers fell behind as mass-market producers. Honda, which was officially founded in Japan on September 24, 1948, introduced their SOHC inline-four engine CB750 in 1969, which was inexpensive and immediately successful. It established the across-the-frame-four engine configuration as a design with huge potential for power and performance. Shortly after the introduction of the SOHC, Kawasaki demonstrated the potential of the four-stroke four-cylinder engine with the introduction of the KZ900. Suzuki, Kawasaki and the Yamaha each started producing motorcycles in the 1950s. Meanwhile, the sun was setting on British dominion over the big-displacement motorbike market. Japanese dominance The excellence of Japanese motorcycles caused similar effects in all Western markets: many Italian bike firms either went bust or only just managed to survive. As a result, BMW's worldwide sales sagged in the 1960s, but came back strongly with the introduction of a completely redesigned "slash-5" series for model year 1970. From the 1960s through the 1990s, small two-stroke motorcycles were popular worldwide, partly as a result of the pioneering work of the East German Daniel Zimmermann (rotary disc valve) and MZ's Walter Kaaden who developed the two-stroke expansion chamber in the 1950s. These ideas were taken up by Suzuki when Ernst Degner, the MZ engineer and rider, defected to the West on 13 September 1961 after retiring from the 125cc Swedish Grand Prix at Kristianstad. Degner, an excellent engineer, immediately joined Suzuki and his knowledge became their technology springboard. Harley-Davidson in the US at the time suffered from the same problems as the European firms, but its unique product range, American tariff laws and nationalism-driven customer loyalty allowed it to survive. One alleged flaw, however, was retaining the characteristic Harley-Davidson 45° engine vee-angle, which causes excess vibration as well as the loping Harley-Davidson sound. A factory full fairing was introduced by BMW motorcycle in the R100RS of 1977, the first factory fairing produced in quantity. In 1980, BMW stimulated the "adventure touring" category of motorcycling with its dual-sport model, the R80G/S. In 1988,