Aprilia ST 125 (1982-84)

The Aprilia ST 125 was a motorcycle produced from 1982 to 1984. It was powered by a two-stroke, single cylinder engine with a capacity of 124cc and a compression ratio of 14.5:1. The bike had a liquid cooling system and used an A28 mm Dell’Orto PHBH AS carburettor for induction. It had electronic ignition and a 12V 5.5 Ah battery with a generator that provided 130W of power. The bike used a kick start and a multi-disc oil bath clutch. It delivered a maximum power of 13.8 Nm / 18.5 hp @ 8250 rpm and had a six-speed transmission and chain final drive. The frame was a double cradle tubular steel design, and the suspension comprised a non-adjustable ~A32mm Marzocchi fork at the front and a swingarm with single shock absorber at the rear. The bike featured a single ~A230 mm disc brake at the front and a ~A160mm drum brake at the rear. It had a front wheel size of 2.75-18 and a rear wheel size of 3.00-18.

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Technical specifications:

Make Model: Aprilia ST 125

Year: 1982 – 84

Engine: Two stroke, single cylinder

Capacity: 124 cc / 7.6 cu in

Bore x Stroke: 52.8 mm x 57mm

Compression Ratio: 14.5:1

Cooling System: Liquid cooled

Induction: ~A28 mm Dell’Orto PHBH AS

Ignition: Electronic

Battery: 12V 5.5 Ah

Generator: 130W

Starting: Kick

Clutch: Multi-disc oil bath

Max Power: 13.8 Nm / 18.5 hp @ 8250 rpm

Transmission: 6 Speed

Final Drive: Chain

Frame: Double cradle tubular steel

Front Suspension: Marzocchi ~A32mm fork. non-adjustable

Rear Suspension: Swingarm with single shock absorber

Front Brakes: Single ~A230 mm disc

Rear Brakes: ~A160mm drum

Front Wheel: 2.75-18

Rear Wheel: 3.00-18