| MODEL | BSA 4.93 HP OHV SLOPER 493 1928 |
| Year | 1928 |
| Engine Type | Inclined single-cylinder four-stroke overhead-valve, two valves at 90 degrees |
| Displacement / Capacity | 493 cc |
| Bore X Stroke | 80 mm x 98 mm |
| Compression Ratio | Low-compression piston standard, high-compression optional (ratio not given) |
| Cooling System | — |
| Max Power | — |
| Max Torque | — |
| Ignition | Gear-driven racing magneto behind the cylinder |
| Induction | Special Amac carburettor with air cleaner |
| Start System | — |
| TRANSMISSION SPECS | |
| Lubrication | Integral 3-pint sump, submerged gear pump driven from the mainshaft |
| Gear Box | BSA three-speed, constant mesh, enclosed kick-starter; close or wide ratio optional |
| Clutch | Large floating dry-plate, left-hand lever, cush drive on engine shaft |
| Final Drive | Chain: front 1/2 x 0.305 in enclosed, rear 5/8 x 3/8 in |
| CHASSIS SPECS | |
| Frame | Duplex loop frame, steering damper, sidecar lugs |
| Front Suspension | BSA spring fork with barrel spring and shock absorbers |
| Rear Suspension | — |
| Front Brakes | Internal expanding, 7 in, left toe pedal (hand lever optional) |
| Rear Brakes | Internal expanding, 7 in, right toe pedal |
| DIMENSION SPECS | |
| Overall Length | — |
| Overall Width | — |
| Overall Height | — |
| Seat Height | 24 in minimum |
| Wheelbase | — |
| Ground Clearance | 4.75 in |
| Dry Weight | — |
| Wet Weight | — |
| WHEEL SPECS | |
| Front Tyre | 26 x 3.25 in or 27 x 2.75 in Dunlop cord wired-on |
| Rear Tyre | 26 x 3.25 in or 27 x 2.75 in Dunlop cord wired-on |
| FUEL SYSTEM | |
| Fuel Capacity | 2.25 Imperial gal (oil sump 3 pints) |
| Fuel Consumption | — |
| Top Speed | — |
This is the sporting overhead-valve sloper, with its steeply inclined cylinder, duplex loop frame and low seat. It was described as quiet running, with a silencer sized to meet Brooklands regulations.
