An 80bhp 500 in 1939? Hard to Swallow

This is the original Gilera Quattro, the 1939 version developed from the 1936 OPRA four that Giuseppe Gilera bought from Count Bonmartini. The OPRA project had been placed into another of Bonmartini’s companies, CNA (Compagnia Nazionale Aeronautica), and he renamed the four cylinder motorcycle Rondine (swallow) which is why you might occasionally read of a CNA Rondine. He brought in another Roman engineer to work with Carlo Gianni and in reality the motorcycle they designed was completely new. 1933 development brought full water cooling and supercharging of the 490cc OPRA four, alongside a much improved chassis.

The Rondine had 45 degree inclined cylinders to allow a supercharger to sit above them. And then in 1934 Bonmartini sold CNA to the aircraft manufacturer Caproni, which had no interest in the Rondine. Ironically Caproni would turn to motorcycle manufacture post war but at this time could not imagine how the world would change. Without Bonmartini’s money there could be no further progress, so rider Piero Taruffi approached Moto Guzzi and Gilera, and possibly Benelli as well, hoping one of them would take on the Rondine. Giorgio Parodi – the money man at Moto Guzzi – was favourably disposed towards the project, but Carlo Guzzi was unconvinced. Giuseppe Gilera, on the other hand, realised that this was a once in a lifetime chance and, as soon as Taruffi had agreed to move from Rome to Arcore where Gilera was based, immediately bought everything associated with the Rondine convinced it was the basis of a fine racing machine. These photographs by Phil Aynsley is the European Championship winning 1939 version. This supercharged Gilera made 80hp at 9,000rpm, a phenomenal output when a cammy Norton made 29bhp and the TT winning supercharged Type 255 BMW RS 500 developed 60. The full story of the rise of the fours – along with much else – is in the 200-odd pages of The Road, available via the shop.

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