Motocross Bikes
2021Yamaha YZ125X
38 fields on record
The 2021 Yamaha YZ125X is a lightweight enduro bike designed for young riders and beginners seeking an affordable entry point into off-road riding. Powered by a nimble 125cc two-stroke engine with liquid cooling and a six-speed transmission, it delivers responsive performance and easy handling on varied terrain. Known for its reliability, low maintenance costs, and excellent maneuverability, the YZ125X excels as a training platform and recreational trail bike.
- Capacity
- 125.0 ccm
- Engine
- Single, two-stroke
- Gearbox
- 6-speed
- Wet weight
- 94.8 kg
- Seat height
- 975 mm
- Power
- 15.0 HP (11.0 kW)
How it rides
Editorial estimate from the spec sheet - not lab tested- Best for
- Built as a cross-country/off-road competition machine, essentially a trail-tuned YZ125 motocrosser with wider-ratio gearing and off-road suspension settings.
- Built for
- Raw, high-strung, and reward-driven, this bike delivers sharp, punchy 2-stroke power and razor-sharp agility for riders who like to work the bike hard.
- Not ideal for
- Not for riders seeking comfort, highway capability, passenger accommodation, or a low-maintenance, easy-going ride.
Scores are derived from the spec sheet using the same model across every bike, so they compare like for like.
Will it fit you?
Worked out in your browser - nothing is sent to usEngine
- Capacity
- 125.0 ccm
- Power
- 15.0 HP (11.0 kW)
- Engine type
- Single, two-stroke
- Power/weight ratio
- 0.1582 HP/kg (wet)
- Bore x stroke
- 54.0 x 54.5 mm
- Compression
- 8.8:1
- Cooling system
- Liquid
- Fuel system
- Carburettor
- Starting
- Kick
- Ignition
- CDI
- Lubrication system
- Premix
Transmission
- Gearbox
- 6-speed
- Transmission type
- Manual
- Final drive
- Chain
Dimensions & weight
- Wheelbase
- 1455 mm
- Overall length
- 2141 mm
- Overall width
- 825 mm
- Overall height
- 1285 mm
- Seat height
- 975 mm
- Wet weight
- 94.8 kg
- Fuel capacity
- 8.00 litres
- Ground clearance
- 351 mm
- Oil capacity
- 0.70 litres
- Dry weight
- Not on record - add it
Chassis & suspension
- Frame
- Semi-double cradle aluminium frame
- Front suspension
- KYB® Speed-Sensitive System inverted fork; fully adjustable
- Rear suspension
- KYB® single shock; fully adjustable
- Front wheel travel
- 300 mm
- Rear wheel travel
- 315 mm
- Rake (fork angle)
- 26.8°
- Trail
- 117 mm
Brakes & wheels
- Front brakes
- Single disc. Hydraulic.
- Front brakes diameter
- 270 mm
- Rear brakes
- Single disc. Hydraulic.
- Rear brakes diameter
- 245 mm
- Front tyre
- 90/90-21
- Rear tyre
- 110/90-18
Other
- Color options
- Team Yamaha Blue
Compiled from manufacturer documentation and user contributions, corrected on an ongoing basis. Spotted something wrong? Tell us.
What changed, year to year
Differences highlighted| Specification | 2017 | 2020 | 2021 | 2022 | 2025 | 2027 |
|---|---|---|---|---|---|---|
| Capacity | 124 cc | 125 cc | 125 cc | 125 cc | 125 cc | 125 cc |
| Seat height | 975 mm | 975 mm | 975 mm | 975 mm | 970 mm | 970 mm |
| Fuel capacity | 8 L | 8 L | 8 L | 8 L | 6.8 L | 6.8 L |
Illustrative - generated automatically by diffing the year records already on file, not a manufacturer-published changelog.
Rider Reviews
Common questions
What is the engine size of the Yamaha YZ125X?
The 2021 Yamaha YZ125X has a Capacity of 125.0 ccm (7.63 cubic inches).
What engine power does the Yamaha YZ125X have?
The 2021 Yamaha YZ125X has a Power of 15.0 HP (11.0 kW).
How many gears does the Yamaha YZ125X have?
The 2021 Yamaha YZ125X has a Gearbox of 6-speed.
How much does the Yamaha YZ125X weigh?
The 2021 Yamaha YZ125X has a Wet weight of 94.8 kg (209.0 pounds).
Shop this bike
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The 2021 Yamaha YZ125X is a powerful and agile off-road motorcycle that is perfect for adrenaline junkies and motocross enthusiasts. With its lightweight frame and responsive handling, the YZ125X offers great maneuverability on challenging terrain. The 125cc liquid-cooled two-stroke engine delivers impressive power and torque, making it an ideal choice for off-road racing and trail riding. The bike's rugged construction and high-quality components ensure durability and reliability, even in the most demanding riding conditions. Overall, the Yamaha YZ125X provides an exhilarating and thrilling riding experience for those who crave adventure and excitement.
In conclusion, the 2021 Yamaha YZ125X is a top-performing off-road motorcycle that delivers thrilling power and performance. Whether you're tearing up the motocross track or exploring rugged trails, the YZ125X is a capable and reliable companion. Its lightweight design, powerful engine, and durable construction make it a standout choice for riders who demand the best in off-road performance. If you're seeking a versatile and high-performing off-road motorcycle, the Yamaha YZ125X is definitely worth considering.
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