MOTOBÉCANE

500 RS & S5C - 1935

Birth of industrial design

The arrival in 1934 of the unit-constructed Motobécane S was intended to correct the

faults of the unit-constructed "B" machine launched in 1930: dubious oil-tightness, hit-and-miss lubrication and outdated styling.

Successful Career

It reached its target, and the S range of 250, 350 and 500cc bikes with either overhead- or side-valves enjoyed a steady career during an uncertain period for the motorcycle.

Styled by Géo Ham

Launched just after new designs from Peugeot and Chaise, the B suffered from its old-fashioned appearance. Conscious of this handicap, the management took the uncommon step of calling in an industrial designer – famed motoring artist Géo Ham, who cleaned up the functional creation of the engineers and gave it style. The result was a clean, sleek bike with much-improved oil-tightness due to a rotary pressure-release valve driven off the magneto gearing. The cycle part – number plate, illuminated license plate, tank trim, knee-grips and muffler – benefited from Ham's talents, and the aesthetic result was favorably received by the market. Launched in 1934 as a three-speeder, the S unit initially powered seven models: the 350 and 500 side-valve "Grand Tourisme," the ohv 250, 350 and 500cc "Grand Luxe," and the 350 and 500cc "Grand Sport" with four overhead-valves; the only models with a foot-shift. A year later came a four-speed with a selector-pedal, standard on the ohv 500cc S5C and optional across the line, which gained a side-valve 250 but lost its ohv 250.

SPECIFICATIONS

Engine: 493cc (80x98mm) air-cooled single-cylinder four-stroke; Novi magneto

Power Rating: 15 or 22 hp

Valves: side (R5) or overhead (S5C)

Fuel System: carburetor

Transmission: 3-speed hand- or foot-shift (optional) or 4-speed selector pedal; multiplate oil-bath clutch; gear primary, chain final drive

Suspension: Webb girder forks (front); rigid (rear)

Brakes: drum (front & rear)

Wheels: 19 inch (front & rear)

Weight: 309 lb (R5); 331 lb (S5C)

Maximum Speed: 60 mph (RS); 78 mph (S5C)

Industrial design was still a novel concept in 1934, when Motobécane hired top automotive illustrator Géo Ham to design its new R and S models.