Yamaha YZ125X
- Production years
- 2017–2026
- Brand
- Yamaha
Choose model year
Model year
1 / 2
Selected year: 2017
Technical specifications
Specifications may vary by market.
- Engine capacity
- 124 cm³
- Power
- 15 hp (11 kW)
- Wet weight
- 93.5 kg
- Seat height
- 975 mm
Overview
The Yamaha YZ125X is a motocross bike from a model family produced from 2017 through 2026. The 2026 model has a 125 cm³ single, two-stroke engine producing 15 hp (11 kW), with a wet weight of 96.2 kg.
At 970 mm, the seat is high and can make it harder for shorter riders to reach the ground. The 300 mm front and 315 mm rear wheel travel, fully adjustable KYB® suspension, and 356 mm ground clearance suit rough terrain and let riders tune the suspension. The 6.8 L tank is smaller than the 8 L tank in 2022, while the seat height fell from 975 mm to 970 mm for 2023. The engine uses premix lubrication and the bike starts by kick.
Specifications
Engine
Engine
- Bore
- 54 mm
- Engine capacity
- 124 cm³
- Compression ratio
- 7.1
- Cooling system
- Liquid
- Engine type
- Single, two-stroke
- Fuel system
- Carburettor
- Ignition
- CDI
- Lubrication system
- Premix
- Oil capacity
- 0.7 L
- Starting
- Kick
- Stroke
- 54.5 mm
Performance and transmission
Performance and transmission
- Power
- 15 hp (11 kW)
- Clutch
- O-ring chain
- Final drive
- Chain
- Gearbox
- 6
- Transmission type
- Manual
Dimensions and weight
Dimensions and weight
- Fuel capacity
- 8 L
- Ground clearance
- 351 mm
- Overall height
- 1,285 mm
- Overall length
- 2,141 mm
- Overall width
- 825 mm
- Seat height
- 975 mm
- Wet weight
- 93.5 kg
- Wheelbase
- 1,443 mm
Chassis and suspension
Chassis and suspension
- Frame
- Semi-double cradle aluminium frame
- Front suspension
- Speed-sensitive system inverted fork
- Front wheel travel
- 300 mm
- Rake
- 26 °
- Rear suspension
- Fully adjustable single shock
- Rear wheel travel
- 315 mm
- Trail
- 109 mm
Brakes and wheels
Brakes and wheels
- Front brakes diameter
- 270 mm
- Front tyre
- 80/100-21
- Rear brakes
- Single disc. Hydraulic.
- Rear brakes diameter
- 245 mm
- Rear tyre
- 100/90-18
Model years
2020
Engine capacity: 124 cm³ → 125 cm³; Wet weight: 93.5 kg → 94.8 kg
2023
Wet weight: 94.8 kg → 96.2 kg; Seat height: 975 mm → 970 mm; Fuel capacity: 8 L → 6.8 L
| Specification | ||||||
|---|---|---|---|---|---|---|
| Engine capacity | 124 cm³ | 124 cm³ | 124 cm³ | 125 cm³ | 125 cm³ | 125 cm³ |
| Power | 15 hp (11 kW) | 15 hp (11 kW) | 15 hp (11 kW) | 15 hp (11 kW) | 15 hp (11 kW) | 15 hp (11 kW) |
| Wet weight | 93.5 kg | 93.5 kg | 93.5 kg | 94.8 kg | 94.8 kg | 94.8 kg |
| Seat height | 975 mm | 975 mm | 975 mm | 975 mm | 975 mm | 975 mm |
| Fuel capacity | 8 L | 8 L | 8 L | 8 L | 8 L | 8 L |
Pros and cons
Advantages
Low wet weight
At 96.2 kg wet, the bike is relatively easy to maneuver at low speeds and when changing direction.
Adjustable KYB® suspension
Both ends are fully adjustable, so riders can tailor the suspension to different terrain and riding preferences.
High ground clearance
The 356 mm clearance helps the bike pass over uneven ground with less risk of striking obstacles underneath.
Things to consider
Kick start only
Starting requires a kick, with no electric-start option listed.
Premix lubrication
The two-stroke engine requires premix, so fuel and oil need to be combined before riding.
Smaller tank than in 2022
The 6.8 L tank carries less fuel than the 8 L tank used in 2022.
Rider fit
Rider fit calculator
Calculated in your browser
Don't know it? Leave this empty and we'll estimate it from your height.
Estimated from your height: 79 cm
How to measure
Stand barefoot with your back to a wall. Hold a book firmly between your legs, then measure from the floor to the top edge of the book.
Estimated ground reach
Ground reach may be difficult
This seat may feel tall. A lower seat or suspension setup could make stops easier.
Seat height
975 mm
Approx. loaded height
945 mm
Estimate assumes about 30 mm of suspension sag. Seat width, footwear, luggage and suspension settings can change real reach. Always sit on the motorcycle before buying.
Fuel range calculator
Enter your expected fuel consumption to estimate the distance on a full tank, with or without a fuel reserve.
Tank 8 L at 6 L/100 km
Lower consumption = longer range.
Estimated range
133 km
With 10% reserve
120 km
This is a planning estimate, not a measured result. Speed, route, weather, load and riding style can change real consumption.
FAQ
What is the weight of Yamaha YZ125X?
The Yamaha YZ125X weighs 93.5 kg (wet weight). For model year 2017.
What are the specs of Yamaha YZ125X?
The Yamaha YZ125X has the following key specifications (specs) for model year 2017: 124 cc; 15 hp (11 kW); 93.5 kg (wet weight); seat height 975 mm; fuel tank 8 L. Specification table
How much horsepower does Yamaha YZ125X have?
The Yamaha YZ125X makes 15 hp (11 kW). For model year 2017.
What is the seat height of Yamaha YZ125X?
The Yamaha YZ125X has a seat height of 975 mm. For model year 2017.
What is the fuel tank capacity of Yamaha YZ125X?
The Yamaha YZ125X has a fuel tank capacity of 8 L. For model year 2017.
