In the 1950s, streamlining began to play an increasing part in the development of racing motorcycles and the "dustbin fairing" held out the possibility of radical changes to motorcycle design. NSU and Moto-Guzzi were in the vanguard of this development both producing very radical designs well ahead of their time. NSU produced the most advanced design, but after the deaths of four NSU riders in the 1954–1956 seasons, they abandoned further development and quit Grand Prix motorcycle racing. Moto-Guzzi produced competitive race machines, and by 1957 nearly all the Grand Prix races were being won by streamlined machines.The following year, 1958, full enclosure fairings were banned from racing by the FIM in the light of the safety concerns. From the 1960s through the 1990s, small two-stroke motorcycles were popular worldwide, partly as a result of East German Walter Kaaden's engine work in the 1950s.Today, the motorcycle industry is mainly dominated by Japanese companies such as Honda, Kawasaki, Suzuki, and Yamaha, although Harley-Davidson and BMW continue to be popular and supply considerable markets. Other major manufacturers include Piaggio group of Italy, KTM, Triumph and Ducati. In addition to the large capacity motorcycles, there is a large market in smaller capacity less than 300 cc motorcycles, mostly concentrated in Asian and African countries. An example is the 1958 Honda Super Cub, which went on to become the biggest selling vehicle of all time, with its 60 millionth unit produced in April 2008.Today, this area is dominated by mostly Indian companies with Hero Honda emerging as the world's largest manufacturer of two wheelers. | 
