The Yamaha DT125MX is a 1981 motorcycle with a two-stroke, single cylinder engine featuring reed valves. It has a 123cc capacity, and a compression ratio of 7.2:1. The lubrication is provided by Autolube, and it has a 0.9-litre oil capacity. Induction is via a single 24mm Mikuni carburettor, and ignition is through a flywheel magneto. The starting mechanism is kick-start only. The motorcycle can generate up to 14 horsepower at 6,500 RPM, and has a maximum torque of 1.5 kgf-m or 15.2 Nm at the same RPM. The clutch is multiplate and wet, with six-speed transmission and a chain final drive. The front suspension comprises telescopic forks and offers a wheel travel of 160mm. The rear suspension consists of a monocross unit, giving a wheel travel of 115 mm. The bike has drum brakes on the front and rear wheels, with tyre sizes of 2.75-21 and 3.50-18. The dimensions of the Yamaha DT125MX are 2080mm x 885mm x 1120 mm, with a wheelbase of 1325 mm and seat height of 855 mm. The ground clearance is 265 mm, and it has a dry weight of 96 kg. The fuel capacity is 7 litres, with an average consumption of 79 mpg. In terms of speed, the bike can reach a top speed of 74 mph and complete a standing 1/4 mile in 19.9 seconds.
Technical specifications:
Make Model: Yamaha DT 125MX
| Year | 1981 |
|---|---|
| Engine | Two stroke, single cylinder, reed-valve |
| Capacity | 123 cc / 7.5 cu-in |
| Bore x Stroke | 56 50 mm |
| Cooling System | Air cooled |
| Compression Ratio | 7.2:1 |
| Lubrication | Autolube |
| Oil Capacity | 0.9 Litres |
| Induction | Single 24 mm Mikuni |
| Ignition | Flywheel Magneto |
| Starting | Kick |
| Max Power | 14 hp / 10.3 kW @ 6500 rpm |
| Max Torque | 1.5 kgf-m / 15.2 Nm @ 6500 rpm |
| Clutch | Wet multiplate |
| Transmission | 6 speed |
| Final Drive | Chain |
| Front Suspension | Telescopic Forks |
| Front Wheel Travel | 160 mm / 6.2 in |
| Rear Suspension | Monocross |
| Rear Wheel Travel | 115 mm / 4.5 in |
| Front Brakes | Drum |
| Rear Brakes | Drum |
| Front Tyre | 2.75-21 |
| Rear Tyre | 3.50-18 |
| Dimensions | Length 2080 mm / 81.8 in Width 885 mm / 34.8 in Height 1120 mm / 41.0 in |
| Wheelbase | 1325 mm / 52.2 in |
| Seat Height | 855 mm / 33.6 in |
| Ground Clearance | 265 mm / 10.4 in |
| Dry Weight | 96 kg / 212 lbs |
| Fuel Capacity | 7 Litres / 1.58 gal |
| Consumption Average | 79 mpg |
| Standing 1/4 Mile | 19.9 sec |
| Top Speed | 74 mph |
