The engine was a 780 cc side-valve, single-cylinder unit, water-cooled, with a bore of 95 mm and stroke of 110 mm.
The capacity increased to 812 cc in 1908 when the bore was increased to 97 mm to bring dimensions into line with Rover's new range of four-cylinder cars.

The engine's normal speed was 1200 rpm.
Selection of top, middle or low gear provided speeds of 24 mph, 16 mph and 8 mph respectively.
The change speed lever mounted in a notched quadrant below the steering wheel is linked by a connecting rod to a vertical spindle in the gearbox.
 Ignition was by High-Tension current from the Bosch magneto, low tension accumulator ignition was also provided.
The crankcase, flywheel and clutch and gearbox enclosures are made up of one pair of aluminium castings.
The upper half is bolted directly to the frame at the front and at the rear is bolted to a thin steel cross-member.

The clutch runs in oil and uses the metal to metal gripping disc system of the 8 hp car.
Drive was taken to the rear wheels through a three-speed gearbox, light but very similar to the earlier car, and jointed drive shaft.
The brake drum at the back of the gearbox surrounds the universal joint, the rear axle casing extends forward to almost the universal joint.
There is a bevel wheel in the differential case.

The engine's throttle is operated by a lever below the steering wheel.
The same lever simultaneously controls the ignition timing.
Petrol is in a tank beneath the driver's seat.
The engine was a 780 cc side-valve, single-cylinder unit, water-cooled, with a bore of 95 mm and stroke of 110 mm. The capacity increased to 812 cc in 1908 when the bore was increased to 97 mm to bring dimensions into line with Rover's new range of four-cylinder cars. 
The engine's normal speed was 1200 rpm. Selection of top, middle or low gear provided speeds of 24 mph, 16 mph and 8 mph respectively. The change speed lever mounted in a notched quadrant below the steering wheel is linked by a connecting rod to a vertical spindle in the gearbox.  Ignition was by High-Tension current from the Bosch magneto, low tension accumulator ignition was also provided. The crankcase, flywheel and clutch and gearbox enclosures are made up of one pair of aluminium castings. The upper half is bolted directly to the frame at the front and at the rear is bolted to a thin steel cross-member.
The clutch runs in oil and uses the metal to metal gripping disc system of the 8 hp car. Drive was taken to the rear wheels through a three-speed gearbox, light but very similar to the earlier car, and jointed drive shaft. The brake drum at the back of the gearbox surrounds the universal joint, the rear axle casing extends forward to almost the universal joint. There is a bevel wheel in the differential case.
The engine's throttle is operated by a lever below the steering wheel. The same lever simultaneously controls the ignition timing. Petrol is in a tank beneath the driver's seat.
Rover 6