| MODEL | YAMAHA DT 125R 1990 - 1991 |
| Year | 1990 - 1991 |
| Engine Type | Two stroke, single cylinder, reed-valve |
| Displacement / Capacity | 123 cc / 7.5 cu in |
| Bore X Stroke | 56 x 50 mm |
| Compression Ratio | 6.8:1 |
| Cooling System | — |
| Max Power | 10.3 kW / 14 hp @ 6500 rpm |
| Max Torque | 15.2 Nm / 1.5 kgf-m @ 6500 rpm |
| Ignition | CDI |
| Induction | VM24 carburetor |
| Start System | Kick |
| TRANSMISSION SPECS | |
| Lubrication | Autolube |
| Gear Box | 6 speed |
| Clutch | Wet multiplate |
| Final Drive | Chain |
| CHASSIS SPECS | |
| Frame | — |
| Front Suspension | Telescopic forks |
| Rear Suspension | Monocross |
| Front Brakes | Single 230 mm disc |
| Rear Brakes | Single 220 mm disc |
| DIMENSION SPECS | |
| Overall Length | 2135 mm / 81.0 in |
| Overall Width | 820 mm / 32.2 in |
| Overall Height | 1255 mm / 49.4 in |
| Seat Height | 840 mm / 33.0 in |
| Wheelbase | 1360 mm / 53.5 in |
| Ground Clearance | 270 mm / 10.6 in |
| Dry Weight | — |
| Wet Weight | 119 kg / 262.4 lbs |
| WHEEL SPECS | |
| Front Tyre | 2.75-21 |
| Rear Tyre | 4.10-18 |
| FUEL SYSTEM | |
| Fuel Capacity | 10 Litres / 2.2 US gal |
| Fuel Consumption | 20 km/L |
| Top Speed | 124.6 km/h / 77.5 mph |
Mechanically unchanged from the 1988-89 DT125R on the opened spec page: 123 cc reed-valve two-stroke, 14 hp, 6-speed box and disc brakes front and rear. A tall, light trail bike aimed at young and learner riders.
