Aprilia’s mini RS, the RS4 125cc four stroke sporty.

Aprilia RS4 125

It seems like theres a lot of small capacity sport style bikes on the market of late. Here in Aus, the 250cc Ninja has been a top seller for years. The smaller capacity 150cc Yamaha R15, and the Honda CBR125 that gets by on one cylinder of 125cc, are more recent arrivals to the market.

Aprilia have jumped into this space with a 125cc sportsbike styled tiddler. While it’s no pocket rocket like the RS125cc 2 smoker that they produced, it’s RSV4 styling looks the goods. 41mm upside down forks, and a 300mm disc with a radial caliper ensure it should turn and stop as well.

Not available in Australia at this time, the RS125 is a single cylinder four stroke, putting out what you or I might consider “not enough” horsepower. Based on a sister bike from the big happy Piaggio family, the Euro limits of 15hp for learners are what this bike maxes out at.

It sure looks good though.

Aprilia RS4 Specifications

Engine

Four stroke liquid cooled single cylinder with electronic injection and 4 valves.
Euro 3 homologated

Bore and stroke 58 X 47 mm

Engine capacity 124.8 cc
Double overhead camshaft – DOHC

Compression ratio 12.5 ± 0.5:1

ECU Magneti Marelli MIU G3 32 mm diam.

Ignition Electronic with CDI capacity discharge
Starting Electric

Alternator 13V – 235W
Lubrication Wet sump
Gearbox: 6 speed.

Frame

Aluminium perimeter frame

Front suspension

41 mm upside down fork, wheel travel 110 mm
Rear suspension Asymmetric swingarm with monoshock, wheel travel 130 mm

Brakes

Front: 300 mm stainless steel disc with radial 4 piston calliper
Rear: 218 mm stainless steel disc and calliper with single 25 mm piston

Wheel rims ; front: 2.75 x 17″; rear: 3.50 x 17″
Tyres Front: 110/80 – 17″, rear: 130/70 – 17″

Dimensions

Max. Length 1953 mm
Max width 740 mm
Max height at top fairing 1,138 mm
Seat height 820 mm
Wheelbase 1,350 mm
Fuel tank capacity 14.5 litres (including 3.5 litre reserve)