The Triumph Speed Twin 500 was produced from 1947 to 1958 and had a four-stroke, parallel twin, OHV engine with a capacity of 498 cc. Its bore and stroke were 63 x 80 mm and had a compression ratio of 7.2:1. The motorcycle was air-cooled, and its fuel was provided by a single Amal carburetor 15/16″ and ignited by a 6V magnetic flywheel. It had a kick-starting mechanism and could produce a maximum power of 20.9 kW / 28 hp at 6000 rpm. The engine was paired with a wet, six-plate clutch and a 4-speed, constant mesh transmission that drove the rear wheel through a chain. The bike had a single tube frame and hydraulic telescopic forks for the front suspension. Between 1947 and 1954, it had a sprung hub for the rear suspension and two shock absorbers after 1954. The front and rear brakes were both drum, with a 7-inch SLS. The bike had Dunlop Universal tires for the front and rear, with sizes of 3.25 – 19 and 3.50 – 19, respectively. The wheelbase measured 1372 mm / 54 in, with a saddle height of 749 mm / 29.5 in and ground clearance of 152 mm / 6.0 in. It weighed 182 kg / 401 lbs and had a fuel capacity of 18 L / 4.8 US gal / 4.0 Imp gal.
Technical specifications:
Make Model: Triumph Speed Twin 500
| Year | 1947-58 |
|---|---|
| Engine | Four stroke, parallel twin, OHV |
| Capacity | 498 cc / 30.4 cub in. |
| Bore x Stroke | 63 x 80 mm |
| Compression Ratio | 7.2:1 |
| Cooling System | Air cooled |
| Induction | Single Amal carburetor 15/16″ |
| Ignition | 6 V magnetic flywheel |
| Starting | Kick |
| Max Power | 20.9 kW / 28 hp @ 6000 rpm |
| Clutch | Wet,6 plate |
| Transmission | 4 Speed, constant mesh |
| Final Drive | Chain |
| Frame | Singe tube frame |
| Front Suspension | Hydraulic telescopic fork |
| Rear Suspension | 1947-1954 sprung hub, after 1954 Swingarm with two shock absorbers |
| Front Brakes | Drum, 7 in SLS |
| Rear Brakes | Drum, 7 in SLS |
| Front Tyre | 3.25 – 19, Dunlop Universal |
| Rear Tyre | 3.50 – 19, Dunlop Universal |
| Wheelbase | 1372 mm / 54 in |
| Saddle Height | 749 mm / 29.5 in |
| Ground Clearance | 152 mm / 6.0 in |
| Dry Weight | 182 kg / 401 lbs |
| Fuel Capacity | 18 L / 4.8 US gal / 4.0 Imp gal |
