Make Model



1939 - 56


Four stroke, single cylinder, OHV


249 cc / 15.2 cub in.
Cooling System Air cooled
Exhaust Single, steel



Magdyno for Military models

Starting Kick start

Max Power

9 kW / 12 hp



Final Drive Chain
Frame Brazed lug construction

Front Suspension

Telescopic with compression damping

Rear Suspension

None, spring loaded saddle

From 1951: Plunger rear suspension

Front Brake 7 in, drum
Rear Brake 7 in, drum

"C11 Steve McQueen"

The BSA C11 was a pre-unit single-cylinder developed before the Second World War from the sidevalve C10. Fitted with overhead valves and displacing 249cc, the C11 was launched in 1939 and continued to be developed into the 1950s. The C11 frame was improved in 1951 when BSA added plunger rear suspension.

Military W-C11
Although British armed forces only used a few BSA C11s as lightweight transport (having selected instead the BSA M20) in 1940, 530 C11s were ordered in military specification by the Office of the High Commission of India. Modifications for war use included a rear carrier over the mudguard, an additional air filter on the fuel tank and a mag dyno in place of the coil.

Problems with the gearboxes were addressed by the model C11G, which was available either with a three speed gearbox and a rigid frame or with a four speed gearbox in the plunger frame. The C11G also had improved front brakes and became popular as a post war commuter motorcycle.

Steve McQueen's C11
Actor Steve McQueen owned a 1951 BSA C11. Painted in British racing green, McQueen's C11 had a chrome tank with green and gold accents and chrome wheels with green spokes. After McQueen's death the C11 was kept by his wife Barbara for many years before being sold by auction.

Source Wikipedia