Two years later Moto Guzzi called him to race in the 500cc World Championship, where he took part in a single race. The same happened the following year with Gilera. Liberati scored his first points in the World Championship in 1953, and his first race victory came in 1956 in the 350cc class.
However, at the end of the season, a dispute with the Gilera factory left him without a ride.
Two years later Moto Morini gave him the opportunity to race again, this time in the 250cc class. Points system from 1950 to 1968:
(key) (Races in italics indicate fastest lap).