The Sunbeam S7 500 motorcycle was produced between 1946-1956 with a total production of 7,658 units including the De Luxe models. It is powered by a 487cc parallel twin, SOHC engine with a maximum power output of 18.6 kW/ 25 hp at 5800 rpm. The engine has a compression ratio of 6.5:1 and is cooled by air/oil. Lubrication is provided by a wet sump and the starting system is kick-start only. The electrical system is a 6V unit. The bike is equipped with a single plate clutch and a 4-speed transmission with shaft final drive. The frame is a twin cradle steel design with telescopic front suspension and plunger spring-loaded saddle rear suspension. The front and rear brakes are both drum, leading shoe, with a diameter of 203mm or 8″. The wheels are 16″ with a front size of 4.50 x 16″ and a rear size of 4.75 x 16″. The bike has a wheelbase of 1400mm or 57″ and a dry weight of 195 kg or 430 lbs. Its top speed is 121 km/h or 75 mph.
Technical specifications:
Make Model: Sunbeam S7 500, S7 500 De Luxe
| Year | 1946 – 56 |
|---|---|
| Production | 7 658 units (inc. De Luxe models) |
| Engine | Parallel twin, SOHC |
| Capacity | 487 cc / 29.7 cu in |
| Bore x Stroke | 70 x 63.5 mm |
| Compression Ratio | 6.5:1 |
| Cooling System | Air/Oil cooled |
| Lubrication | Wet sump |
| Starting | Kick |
| Electrical system | 6V |
| Max Power | 18.6 kW / 25 hp @ 5800 rpm |
| Clutch | Single plate, dry |
| Transmission | 4-Speed |
| Final Drive | Shaft |
| Frame | Twin cradle, steel |
| Front Suspension | Telescopic, one way damped |
| Rear Suspension | Plunger, spring loaded saddle |
| Front Brakes | Drum, leading shoe, 203 mm / 8″ |
| Rear Brakes | Drum, leading shoe, 203 mm / 8″ |
| Wheel, Front | 4.50 x 16″ |
| Wheel, Rear | 4.75 x 16″ |
| Wheelbase | 1400 mm / 57″ |
| Dry Weight | 195 kg / 430 lbs |
| Top Speed | 121 km/h / 75 mph |
| Source | Sump Publishing |
