Yamaha RD125 (1974-75)

The Yamaha RD125 was a motorcycle produced between 1974 and 1975. It had a 124cc two-stroke parallel twin engine and was air-cooled with a compression ratio of 6.8:1. The bike had a maximum power of 17 horsepower at 8500 rpm and a maximum torque of 1.3 kgf-m at 8000 rpm. It had a 5-speed transmission and a chain final drive. The frame was made of steel tubing with the engine used as a stressed member. The front suspension consisted of 28mm telescopic forks and the rear suspension was dual rear shock pre-load adjustable. The bike had front and rear drum brakes, with a front tyre size of 2.75-18 and a rear tyre size of 3.00-18. The wheelbase was 1245mm and the seat height was 749mm, with a wet weight of 115 kg and a fuel capacity of 11.5 litres. The standing 1/4 mile time for the bike was 18.2 seconds and its top speed was 81 mph.

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Technical specifications:

Make Model: Yamaha RD 125

Year: 1974 – 75

Engine: Two stroke, parallel twin

Capacity: 124 cc / 7.6 cu-in

Bore x Stroke: 43 43 mm

Cooling System: Air cooled

Compression Ratio: 6.8:1

Induction: 2x 18mm Teikei carburetors

Ignition: Battery coil

Starting: Kick

Max Power: 17 hp / 12.4 kW @ 8500 rpm

Max Torque: 1.3 kgf-m @ 8000 rpm

Transmission: 5 Speed

Final Drive: Chain

Gear Ratio: (1) 34.52 (2) 19.67 (3) 14.11 (4) 11.34 (5) 9.11

Frame: steel tube engine used as a stressed member

Front Suspension: 28 mm telescopic forks

Rear Suspension: Dual rear shock pre-load adjustable

Front Brakes: 150 mm Drum

Rear Brakes: 130 mm Drum

Front Tyre: 2.75-18

Rear Tyre: 3.00-18

Wheelbase: 1245 mm / 49.0 in

Seat Height: 749 mm / 29.5 in

Wet Weight: 115 kg / 255 lbs

Fuel Capacity: 11.5 Litres / 3.04 US gal

Standing 1/4 Mile: 18.2 sec

Top Speed: 81 mph