| MODEL | BSA 4.93 HP SIDE-VALVE 493 1928 |
| Year | 1928 |
| Engine Type | Single-cylinder four-stroke side-valve |
| Displacement / Capacity | 493 cc |
| Bore X Stroke | 80 mm x 98 mm |
| Compression Ratio | — |
| Cooling System | — |
| Max Power | — |
| Max Torque | — |
| Ignition | Chain-driven magneto |
| Induction | Amac carburettor |
| Start System | — |
| TRANSMISSION SPECS | |
| Lubrication | Gravity feed to a mechanical pump with sight feed to the crankcase, hand pump for emergencies |
| Gear Box | BSA three-speed, constant mesh, widened for strength, enclosed kick-starter |
| Clutch | Floating dry-plate, left-hand lever |
| Final Drive | Chain: front 1/2 x 0.305 in, rear 5/8 x 1/4 in |
| CHASSIS SPECS | |
| Frame | Weldless steel tube with forged lugs, sidecar lugs |
| Front Suspension | BSA spring fork with shock absorbers |
| Rear Suspension | — |
| Front Brakes | Internal expanding, 5.5 in |
| Rear Brakes | Internal expanding, 7 in, toe pedal |
| DIMENSION SPECS | |
| Overall Length | — |
| Overall Width | — |
| Overall Height | — |
| Seat Height | — |
| Wheelbase | — |
| Ground Clearance | — |
| Dry Weight | — |
| Wet Weight | — |
| WHEEL SPECS | |
| Front Tyre | 27 x 2.75 in or 26 x 3.25 in Dunlop cord wired-on |
| Rear Tyre | 27 x 2.75 in or 26 x 3.25 in Dunlop cord wired-on |
| FUEL SYSTEM | |
| Fuel Capacity | 3.5 Imperial gal (oil 3.5 pints) |
| Fuel Consumption | — |
| Top Speed | — |
A large side-valve single sold as a dual-purpose machine, equally at home solo or hauling a sidecar. Options such as a sports engine, steering damper and knee grips were offered at extra cost.
