For 2019 and 2020 the RSV4-styled RS 125 carried on unchanged underneath, still a Euro 4 fuel-injected 125 cc single tuned to the 15 hp learner limit.
| MODEL | APRILIA RS 125 2019 - 2020 |
| Year | 2019 - 2020 |
| Engine Type | Single cylinder, four-stroke, DOHC, 4 valves |
| Displacement / Capacity | 124.2 cc / 7.6 cu in |
| Bore X Stroke | 58 x 47 mm / 2.28 x 1.85 in |
| Compression Ratio | 12.5:1 |
| Cooling System | Liquid cooled |
| Max Power | 11 kW / 15 hp @ 10750 rpm |
| Max Torque | 10.9 Nm / 8.0 lb-ft @ 8250 rpm |
| Ignition | Electronic CDI |
| Induction | Electronic fuel injection, Magneti Marelli M3G ECU, 32 mm throttle body |
| Start System | Electric |
| TRANSMISSION SPECS | |
| Lubrication | Wet sump |
| Gear Box | 6-speed |
| Clutch | Wet multi-plate, cable operated |
| Final Drive | Chain, 13/60 |
| CHASSIS SPECS | |
| Frame | Aluminium perimeter (twin-spar) frame with bolted subframe |
| Front Suspension | 41 mm upside-down fork, 110 mm / 4.3 in travel |
| Rear Suspension | Asymmetric aluminium swingarm, monoshock with adjustable spring preload, 120 mm / 4.7 in travel |
| Front Brakes | Single 300 mm / 11.8 in disc, radial 4-piston caliper, Bosch ABS |
| Rear Brakes | Single 218 mm / 8.6 in disc, 1-piston floating caliper |
| DIMENSION SPECS | |
| Overall Length | 1968 mm / 77.5 in |
| Overall Width | 760 mm / 29.9 in |
| Overall Height | 1135 mm / 44.7 in |
| Seat Height | 820 mm / 32.3 in |
| Wheelbase | 1353 mm / 53.3 in |
| Ground Clearance | — |
| Dry Weight | 135 kg / 297.6 lbs (with ABS) |
| Wet Weight | 144 kg / 317.5 lbs |
| WHEEL SPECS | |
| Front Tyre | 100/80-17 |
| Rear Tyre | 130/70-17 |
| FUEL SYSTEM | |
| Fuel Capacity | 14.5 Litres / 3.8 US gal |
| Fuel Consumption | 2.6 L/100 km / 90.5 US mpg |
| Top Speed | — |
For 2019 and 2020 the RSV4-styled RS 125 carried on unchanged underneath, still a Euro 4 fuel-injected 125 cc single tuned to the 15 hp learner limit. The visible change was the paint: black became the dominant colour in place of the grey used on the first two years of this generation. It remained the last version with the big-bike RSV4 face before the 2021 Euro 5 restyle.
