1933 French Jonghi Side-Valve Record Breaker

Well, it’s not just Harley that thought they could successfully built a side-valve racing bike…

Jonghi was formed in France in early1930, from the meeting in Italy of Tito Jonghi, an Argentinian businessman, and Guiseppe Remondini, a motorcycle engineer. Their aim was to built the fastest 350cc of the day and their fame soon grew…

Obviously, the OHV version was the preferred choice for the amateur, but the side-valve version was still faster than most 500cc OHV of the day. In 1933, the firm was still in the process of building a full works 250 DOHC and their 350 OHV had already won everything they wished. Guiseppe wanted a new challenge and the result was this amazing 350cc side-valve Record Breaker…

They went to the nearby Montlhery concrete banking in early March where the bike showed a speed of nearly 90 mph, 145 kmh, so they attacked the 24 hour world record. The chosen riders were Hector Andreino, Louis Jeannin and Marcel Perrin. They took turn for around one-hour shifts on the bike; as the ride around the concrete bowl was most monotonous and harsh, due to no rear springing, no saddle springs and only a modicum of travel for the front Webbs type forks…

They averaged 125kmh, 78mph, for 18 hours, when a bolt came loose and got stuck between the crankcase and the external flywheel. That created a lot of vibration so they slowed down somewhat but did finish the 24 hour stint and got the record at 116,785 kmh, 72,58 mph, also valid up to the 750 class, not a bad achievement…

Click on thumbs for photo…

Patrick