Photo ou archives : F-M. Dumas
7711
MOTOSACOCHE
500 Model 2 C 10 F (Type Franconi) - 1923
Famous Swiss twins
The most famous of the many Geneva-based motorcycle constructors, Motosacoche began making V-twins in 1913, with a 6 hp 730cc unit – the company's first F-head engine. It was soon followed by a 495cc V-twin available with the option of either F-head (overhead intake, side exhaust) or overhead-valve cylinders.
Common Parts
These two versions, which were produced until the late 1920s, had identical crankcases, with the same magneto and camshaft drives. As a result of this standardization, the pushrods and rockers on the ohv 2 C 10 model were asymmetrical and looked very odd.
Offset Pushrods
The inner pushrods operated the exhaust valves through very short rockers, while the outer pushrods actuated the exhaust valves with excessively long rockers (inset photo). From this overhead-valve model, some extremely sporty and powerful versions were developed in the early 1920s, the best-known of which was ridden with much success by François Franconi, the most famous Swiss rider of his day. The 2 C 10 F (for Franconi) won, among other events, one of the first of the terrible hill-climbs on the Col du Klausen in Switzerland. With a similar model, the Swiss Augusto Rossi set, on August 26, 1923, a staggering record of 106.5 mph over a flying kilometer. The former world record, set by an Indian in the US, was 103.6 mph.
SPECIFICATIONS
Engine: 495cc (64x77mm) air-cooled V-twin four-stroke
Power Rating: over 20 hp (on methanol)
Valves: overhead
Fuel System: single carburetor
Transmission: 3-speed hand-shift, chain final drive
Suspension: girder telescopic forks with triple springs (front); rigid (rear)
Brakes: rim (front & rear)
Wheels: wire clincher (front & rear)
Weight: 276 lb
Maximum Speed: 81 mph (on gasoline)
The extremely rare 2 C 10 F of François Franconi taking part in the 1993 commemorative hill-climb on the Col du Klausen (Switzerland) – which it won in the 1920s.