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.


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

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