| General |
| Year | 2012 - 13 | 2025 |
| Make Model | Aprilia RS4 125 | Harley Davidson Sportster S |
| Dimensions |
| Seat Height | 820 mm / 32.3 in | 765 mm / 30.1 in |
| Wheelbase | 1350 mm / 53.1 in | 1520 mm / 59.8 in |
| Ground Clearance | - | 90 mm / 3.5 in |
| Height | 1138 mm / 44.6 in | 1085 mm / 42.7 in |
| Length | 1953 mm / 76.8 in | 2270 mm / 89.42 in |
| Seat Height (Laden) | - | 734 mm / 28.9 in |
| Width | 740 mm / 29.1 in | 840 mm / 33.1 in |
| Weights & Capacities |
| Dry Weight (kg) | 122 | 221 |
| Wet Weight (kg) | - | 228 |
| Dry Weight | 122 kg / 269 lbs | 221 kg / 487 lbs |
| Fuel Capacity | 14.5 Liters / 3.8 gal | 11.7 Litres / 3.1 US gal |
| Wet Weight | - | 228 kg / 502 lbs |
| Performance |
| Max Power | 11.7 kW / 16 hp @ 10500 rpm | 121 hp / 90 kW @ 7500 rpm |
| Max Torque | 11 Nm / 1.12 kgf-m / 8.1 ft/lb @ 8500 rpm | 126 Nm / 93 lb-ft @ 6000 rpm |
| Engine |
| Displacement | 124.8 cc / 7.6 cu in | 1252 cc / 76.4 cu-in |
| Engine Detail | Four stroke, single cylinder, DOHC, 4 valves | Four stroke, 60° V-twin Revolution Max 1250, Chain-driven, DOHC, hydraulic self-adjusting lifters, intake & exhaust VVT, four valves per cylinder |
| Bore x Stroke | 58 X 47 mm | 105 x 72.3 mm |
| Compression Ratio | 12.5 ± 0.5:1 | 12.0:1 |
| Cooling System | Liquid cooled | Liquid cooled |
| Emissions | Euro 3 | - |
| Exhaust | - | 2-into-1-into-2, catalyst in muffler |
| Fuel Induction | Electronic injection | Electronic Sequential Port Fuel Injection (ESPFI) |
| Ignition | Electronic with CDI capacity discharge | - |
| Lubrication | - | Semi-dry sump |
| Starter | Electric | Electric |
| Drivetrain |
| Clutch | Multiple discs, in oil bath | Mechanical, 8 plate wet, assist & slip, 1090N |
| Final Drive | Chain | Belt, 34/80 ratio |
| Gear Ratios | 1st 11/33 (0.33) / 2nd 15/30 (0.50) / 3rd 18/27 (0.67) / 4th 20/24 (0.83) / 5th 25/27 (0.92) / 6th 23/22 (1.05) | 1st 12.21 / 2nd 9.022 / 3rd 6.994 / 4th 5.641 / 5th 4.731 / 6th 4.131 |
| Primary Drive | - | Gear, 49/89 ratio |
| Transmission / Drive | 6 Speed | 6 Speed |
| Chassis |
| Frame Type | Aluminum perimeter frame | Stressed-member, high strength low alloy steel trellis frame; stamped, cast, and forged junctions; MIG welded; aluminum forged mid-structure |
| Suspension - Front | ø41 mm Upside down fork | 43 mm inverted fork with compression, rebound and spring preload adjustability. Aluminium fork triple clamps |
| Suspension - Rear | Asymmetric swingarm with monoshock | Linkage-mounted, piggyback monoshock with compression, rebound and hydraulic spring preload adjustability |
| Fork Angle | - | 28° |
| Lean Angle | - | 35° |
| Rake | - | 30° |
| Swingarm | - | High strength low alloy steel, tubular sections, stamped x-member, forged axle junctions; MIG welded |
| Trail | - | 148 mm / 5.8 in |
| Wheel Travel - Front | 110 mm / 4.3 in | 92 mm / 3.6 in |
| Wheel Travel - Rear | 130 mm / 5.1 in | 82 mm / 3.2 in |
| Electronics |
| ECU | Magneti Marelli MIU G3, Ø32 mm | - |
| Wheels & Brakes |
| Brakes - Front | Single Ø300 mm disc, 4 piston caliper | Single 320mm rotor, radially mounted, monoblock, 4-piston caliper |
| Brakes - Rear | Single Ø218 mm disc, 1 piston caliper | Single 260mm solid uniform expansion rotor, floating single piston caliper |
| ABS | - | Standard |
| Rims - Front | - | 4.5 x 17 |
| Rims - Rear | - | 5.0 x 16 |
| Tyres - Front | 110/80 -17 | 160/70TR17 73V Dunlop- Harley-Davidson Series, radial, GT503 |
| Tyres - Rear | 130/70 -17 | 180/70R16 77V Dunlop- Harley-Davidson Series, radial, GT503 |
| Wheels | - | Aluminum cast, satin black |