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1957 marked the end of a Golden Era in Grand Prix motorcycle racing. There had been an impressive variety of machinery competing during the 1950s including, works teams from AJS, Norton, Gilera, MV Agusta, Moto Guzzi, and BMW. That's six factories taking part with singles, twins and four-cylinder machines. Include privateer Nortons and Matchless and it made for a colorful competition.
Then the Italian firms dropped a bombshell by announcing they would pull out of racing at the conclusion of the 1957 season, citing escalating costs and dwindling motorcycle sales. MV Agusta initially went along with the pull out before reconsidering. The firm would go on to claim 17 consecutive 500cc crowns.
1957 would also mark a new era in other respects with the banning of the dustbin fairings due to their dangerous instability in crosswinds. Another harbinger of change was the introduction of two-stroke engines in competition. An East German firm named MZ placed respectably in races at the Nürburgring although few people viewed the two-strokes as a threat to the mighty four-strokes.
Points were awarded to the top six finishers in each race. Only the four best races were counted in all five classes: the Sidecars, 125cc, 250cc, 350cc and 500cc championships.
Each constructor is awarded the same number of points as their best placed rider in each race.
As Mondial and MV Agusta had equal number of points, identical ranks obtained in all races, and equal number of races in which they classified, their finishing time in each of the six races was added up. Mondial's total time (5:20:51.8) is quicker than MV Agusta's total time (5:22:38.1), and was declared the constructors' champion.