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2021 Yamaha YZ125 [Model Overview]

2021 Yamaha YZ125

The 2021 Yamaha YZ125: MotoCross Perfection For The Junior Classes

The 2021 YZ125 is the first step into serious competition from Yamaha. Powered by a 125cc 2-stroke, liquid-cooled single cylinder, the bike is designed by the Japanese manufacturer for everything from weekend motocross to national and world class competition.

Like other off-road bikes in the 2021 model lineup, the no-compromises mentality of the YZ125 shows through with a full suite of competition parts already fitted from the factory. KYB fully adjustable front and rear shocks, with 48mm inverted forks up front travelling 11.8 inches and the adjustable link monocross at the rear giving 12.4 inches of travel.

Braking is through a 270mm floating disc up front, clamped by a 2-piston competition caliper, and a 245mm disc out back with a single-piston competition caliper. The front wheel is 21 inches in diameter, with the rear at 19 inches. Ground clearance is at 14.4 inches (365 mm).

As well, in Europe and Canada, there is a version called the YZ125X, with the only difference being a higher compression ratio and the addition of Yamaha’s Power Valve System (YPVS) to make the bike suitable for cross-country and hill-scramble competition.

The 2021 Yamaha YZ125 starts at $6,699 USD / $7,599 CAD, with the YZ125X at $7,799 CAD.

On this page: we’ve curated specs, features, news, photos/videos, etc. so you can read up on the new 2021 Yamaha YZ125 in one place.

2021 Yamaha YZ125

Model Overview

General Info

  • Price: $6,699 USD / $7,599 CAD
  • Key Features:
    • Competition spec suspension and brakes
    • Designed to be 100% compliant with all 125cc motocross regulations
    • Full aluminum double-cradle frame with detachable rear subframe for repairs and replacement between heats.

Main Specs

  • Engine Type: 125cc single 2-stroke, liquid cooled
  • Horsepower: Not provided by manufacturer
  • Torque: Not provided by manufacturer
  • Wet Weight: 161 lbs (73 kg)
  • Seat Height: 33.1 inches (840 mm)


2021 Yamaha YZ125

2021 Yamaha YZ125 Specifications

From Yamaha


Engine 125cc single 2-stroke, liquid cooled
Power Not provided by manufacturer
Bore x Stroke
54.0mm x 54.5mm
Compression Ratio
Fuel System
Mikuni® TMX 38
Starter Electric


Clutch Multiplate wet clutch
Constant-mesh 6-speed
Final Drive Chain


Suspension Front
KYB® Speed-Sensitive System inverted fork; fully adjustable, 11.8-in travell
Suspension Rear
KYB® single shock; fully adjustable, 12.4-in travel
Brakes Front Hydraulic disc, 270mm
Brakes Rear
Hydraulic disc, 245mm
Tires Front
80/100-21 Dunlop® MX52
Tires Rear
100/90-19 Dunlop® MX52
Fuel Tank Capacity
2.1 gal
Color Team Yamaha Blue


Spark Plugs
Headlight LED
Tail Light LED


Overall Length
84.1 in
Overall Width 32.6 in
Overall Height 51.0 in
56.8 in
Ground Clearance
14.4 in
Seat Height
38.4 in
Wet Weight
207 lb


Warranty 1 Year (Limited Factory Warranty)

2021 Yamaha YZ125

2021 Yamaha YZ125 Features


Modern Styling
The front fender, front number plate, radiator shrouds, side number plates, air box, rear fender, fork guards, as well as the rear brake disc protector, rear brake caliper protector and wider foot pegs offer modern, aggressive styling —just like the 4-strokes.
Lightweight Frame
A light aluminum frame houses a patented YPVS™-equipped ripper of an engine for an awesome power-to-weight ratio.
Race-Ready Features
Complete with an aluminum handlebar, titanium foot pegs and gripper seat, the YZ125 is ready to race out of the crate.
Ideal Balance
A pure motocross machine, the light and nimble YZ125 is the perfect choice for riders stepping up from the 85cc class.
Rider-Friendly Chassis
Ultra light weight means nimble handling and less fatigue.
270mm Front Brake
The large 270mm front disc brake coupled with high-performance pad material offers outstanding machine control and performance, plus exceptional stopping power and controllability.


Two-Stroke Power
Amazingly compact 124cc reed-valve-inducted two-stroke helps produce an awesome power-to-weight ratio.
Race-Developed Intake
Reed-valve spacer improves acceleration across the entire powerband.
Yamaha Power Valve System
Patented YPVS™ combines crisp, hard-hitting bottom-end acceleration with strong midrange and eye-opening top-end.
Close-Ratio Transmission
Six-speed, close-ratio transmission optimizes gear ratios for maximum performance.
Digital Ignition
Digital CDI system delivers precise spark and monitors engine speed to ensure optimal timing for faster, stronger response during hard acceleration.
High-Capacity Radiator
Large-capacity radiator features a 10-row core with four louvers to deliver maximum cooling efficiency at all performance levels.


270mm Front Brake
Large 270mm front disc brake coupled with high-performance pad material offers outstanding machine control and performance, plus exceptional stopping power and controllability.
Aluminum Frame
A carefully engineered, advanced aluminum frame and swingarm give the YZ125 the best handling in its class.
Lightweight Subframe
Removable aluminum rear subframe is constructed of square-section tubing for reduced weight.
Industry-Leading Fork
The Speed-Sensitive System 48mm KYB® fork and the damping force are controlled by the piston speed for a smoother, more precise ride with 11.8 inches of travel.
Advanced KYB® Shock
Rear, fully adjustable KYB® shock features reduced-friction Kashima Coat™ internals, 12.4 inches of travel, separate adjusters for high- and low-speed compression damping and a full lock oil rebound system for increased comfort. All add up for fantastic rear wheel control and a sweet ride.
Race-Ready Tires
Premium Dunlop® knobbies offer race-spec traction and wear.


Race-Ready Features
Complete with an aluminum handlebar, 2-position adjustable handlebar clamp, wide foot pegs, gripper seat and adjustable clutch lever with works-style cable adjuster, the YZ250 is ready to race out of the crate.

2021 Yamaha YZ125 Photos

2021 Yamaha YZ125 Videos

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