In 1955 he divided his time between the 250cc and 500cc classes , this time for the MV Agusta factory , with whom he raced for until 1958 .
In 1954 Masetti was again in the 500cc class with Gilera .
In 1955 Masetti divided Masetti 's time between the 250cc and 500cc classes , this time for the MV Agusta factory , with whom he raced for until 1958 .
In 1954 Masetti was again in the 500cc class with Gilera .