
| MODEL | BSA MC1 RACER (250 CC) 1952 |
| Year | 1952 |
| Engine Type | Four-stroke, horizontal single, DOHC, bevel-driven camshafts, 4 valves |
| Displacement / Capacity | 248.5 cc / 15.2 cu in |
| Bore X Stroke | 70 x 64.5 mm |
| Compression Ratio | 10.1:1 |
| Cooling System | Air-cooled |
| Max Power | 25 kW / 34 hp @ 10250 rpm |
| Max Torque | — |
| Ignition | — |
| Induction | 2 x Amal |
| Start System | — |
| TRANSMISSION SPECS | |
| Lubrication | Dry sump |
| Gear Box | 4-speed |
| Clutch | Dry, multi-plate |
| Final Drive | Chain |
| CHASSIS SPECS | |
| Frame | Tubular, double cradle |
| Front Suspension | Leading link |
| Rear Suspension | Mono shock |
| Front Brakes | Drum |
| Rear Brakes | Drum |
| DIMENSION SPECS | |
| Overall Length | — |
| Overall Width | — |
| Overall Height | — |
| Seat Height | — |
| Wheelbase | — |
| Ground Clearance | — |
| Dry Weight | 113 kg / 248 lb |
| Wet Weight | — |
| WHEEL SPECS | |
| Front Tyre | — |
| Rear Tyre | — |
| FUEL SYSTEM | |
| Fuel Capacity | 26 Litres / 7 US gal |
| Fuel Consumption | — |
| Top Speed | 177 km/h / 110 mph |
Bert Hopwood's post-war experiment: a horizontal-cylinder 250 single with chain and bevel-driven overhead cams, developed by Doug Hele. A prototype lapped a banked test track at 104 mph, but BSA management never committed to racing it.