| MODEL | VELOCETTE USS 1929 |
| Year | 1929 |
| Engine Type | Two-stroke, single cylinder |
| Displacement / Capacity | 249 cc / 15.2 cu in |
| Bore X Stroke | 63 x 80 mm |
| Compression Ratio | — |
| Cooling System | Air cooled |
| Max Power | — |
| Max Torque | — |
| Ignition | — |
| Induction | — |
| Start System | Kick start |
| TRANSMISSION SPECS | |
| Lubrication | — |
| Gear Box | 3-speed, hand-controlled |
| Clutch | — |
| Final Drive | Chain |
| CHASSIS SPECS | |
| Frame | — |
| Front Suspension | Webb forks |
| Rear Suspension | Spring-loaded saddle |
| Front Brakes | Drum |
| Rear Brakes | Drum |
| DIMENSION SPECS | |
| Overall Length | — |
| Overall Width | — |
| Overall Height | — |
| Seat Height | — |
| Wheelbase | — |
| Ground Clearance | — |
| Dry Weight | — |
| Wet Weight | — |
| WHEEL SPECS | |
| Front Tyre | — |
| Rear Tyre | — |
| FUEL SYSTEM | |
| Fuel Capacity | — |
| Fuel Consumption | — |
| Top Speed | — |
The USS was the sports version of the Model U two-stroke, with a detachable cylinder head. The 1929 bikes were the last to use Velocette's overhung-crank two-stroke layout, which was simple and cheap to build, before the design changed for 1930.
