The Yamaha ST 125 motorcycle specifications include a 125 cc (7.63 cu in) engine, power of 36 hp (26.3 kW), a 6-speed gearbox, and a listed weight of 110 kg (242.5 lb).
Key specifications
How the Yamaha ST 125 compares
This compares the motorcycle with all Yamaha models in this specifications database. The blue marker is this model and the grey line is the Yamaha database average.
About 32% lower than the Yamaha database average. Around the 47th percentile across Yamaha models.
About 77% lower than the Yamaha database average. Around the 25th percentile across Yamaha models.
About 23% smaller than the Yamaha database average. Around the 35th percentile across Yamaha models.
Yamaha database percentile rankings
Percentiles show where this motorcycle sits across the Yamaha specifications database. They are descriptive database rankings, not performance ratings.
36 hp — more powerful than about 47% of Yamaha models with power data.
125 cc — larger displacement than about 25% of Yamaha models.
10 L — larger than about 35% of Yamaha fuel tanks in this database.
Mechanical overview
Additional useful specifications
| Front tire size | 2.00-17 |
|---|---|
| Rear tire size | 2.00-17 |
| Estimated theoretical fuel range | 125 km |
| Power-to-weight ratio | 0.327 hp/kg |
| Power-to-weight | 327.3 hp/tonne |
| Specific power | 288.0 hp/L |
Model information
| Year released | 1998 |
|---|
Engine specifications
| Engine type | Single cylinder, two-stroke |
|---|---|
| Displacement | 125 cc (7.63 cu in) |
| Power | 36 hp (26.3 kW) |
| Cooling system | Liquid |
| Fuel system | Carburettor. Mikuni |
| Fuel control | Port control |
| Ignition | electronic |
| Starter | Kick |
| Lubrication | Oil injection |
Transmission and drivetrain
| Gearbox | 6-speed |
|---|---|
| Final drive | Chain (final drive) |
| Clutch | Wet plate |
Chassis and suspension
| Frame | Steel deltabox |
|---|---|
| Front suspension | Rwu forks |
| Rear suspension | Monoshock |
Brakes, wheels and tires
| Front brakes | Single disc. Twin piston caliper |
|---|---|
| Rear brakes | Single disc. Twin piston caliper |
| Front tire | 2.00-17 |
| Rear tire | 2.00-17 |
Dimensions and weight
| Dry weight | 110 kg (242.5 lb) |
|---|
Fuel and emissions
| Fuel capacity | 10.00 L (2.64 US gal) |
|---|---|
| Fuel consumption | 8.00 L/100 km (12.5 km/l or 29.40 mpg) |
| Greenhouse gases | 185.6 CO 2 g/km. (CO2 – Carbon dioxide emission) |
Performance
| Top speed | 160.0 km/h (99.4 mph) |
|---|---|
| Power/weight ratio | 0.3273 hp/kg |
Other specifications
| Color options | Purple/ silver |
|---|---|
| Exhaust system | Single expansion chamber and muffler |
| Comments | Made by Yamaha Thailand model code 4XC |
Disclaimer: Specifications may vary by market, trim, production date and optional equipment, and scraped or historical data can contain errors. Comparison and percentile values are calculated from Yamaha models in this specifications database. Always double-check important specifications against the motorcycle owner’s/service manual and official Yamaha information before relying on them. Visit the official Yamaha website.