Manufactured from 1964 to 1980, the scooter has an engine with a displacement of 50cc and 4HP at 6500rpm. There were several versions of the scooter: the first one, built from 1964 to 1968, the second, the KR 51/1, manufactured between 1968 to 1971 and the KR 51/1 K, produced from 1974 until 1980. They all had the same power and a compression ratio of 9.5:1.