The YZ125 has 35 horsepower, while the YZ250F has about 42 horsepower. Both bikes come with a 2-stroke engine with liquid cooling system. Wheels, brakes and suspension are the same in both these bikes, but slight differences can be seen in their dimensions, such as the height of YZ125 is 51 inches while that of YZ250 is 50.8 inches.
2024 Yamaha YZ125
The 2024 Yamaha YZ125 boasts an advanced KYB® Shock with fully adjustable features, providing exceptional rear wheel control and class-leading capability. Its carefully designed ergonomics include a flatter seat, narrow fuel tank, and slim body panels, allowing riders greater freedom of movement for increased control and confidence. The high-performance braking system, along with the industry-leading KYB® Fork with Speed Sensitive System, further contributes to the bike’s outstanding chassis and suspension features.
The lightweight and finely tuned chassis contribute to nimble handling, providing beginners with a bike that is easy to maneuver.
2024 Yamaha YZ250
Yamaha YZ250 powered by a 249 cc liquid-cooled 2-stroke engine with reed-valve induction, this motocross bike offers a potent blend of performance and efficiency. The Hitachi Astemo® Keihin PWK38S carburetor ensures smooth fuel delivery, while the 1.8-gallon fuel capacity keeps the adventure going.
Yamaha YZ250 features KYB® Speed-Sensitive System inverted fork in the front and a KYB® single shock in the rear—both fully adjustable. With a 27.7° rake, 4.8-inch trail, and generous suspension travel, it handles diverse terrains with ease.
Top Speed
The top speed of a Yamaha YZ125 dirt bike is almost 60 miles per hour while The top speed of a Yamaha YZ250 is 80 miles per hour.
SPECIFICATION : YZ125 vs YZ250
ENGINE
| Specification | YZ125 Details | YZ250 Details |
| Engine | 2-stroke, 2-stroke; reed-valve induced | 2-stroke; reed-valve induced |
| Cooling | Liquid | Liquid |
| Displacement | 125 cc | 249 cc |
| Bore x Stroke | 2.1 in. x 2.1 in. (54 mm x 54.5 mm) | 2.6 x 2.8 in. (66.4 x 72 mm) |
| Compression Ratio | 8.2 ~ 10.1:1 | 8.9 ~ 10.6:1 |
| Clutch | Multiplate wet | Multiplate wet |
| Carburetion | Hitachi Astemo® Keihin PWK38S carburetor | Hitachi Astemo® Keihin PWK38S |
| Fuel Capacity | 1.8 gal. | 1.8 gal. |
| Transmission | Constant-mesh 6-speed | Constant-mesh 5-speed |
| Final Drive | Chain | Chain |
BRAKES
| Specification | YZ125 Details | YZ250 Details |
| Front | Hydraulic disc, 270 mm | Hydraulic disc, 270 mm |
| Rear | Hydraulic disc, 240 mm | Hydraulic disc, 240 mm |
WHEELS / TIRES
| Specification | YZ125 Details | YZ250 Details |
| Front | 80 / 100-21 Bridgestone® Battlecross X20F | 80 / 100-21 Dunlop® Geomax MX33F |
| Rear | 100 / 90-19 Bridgestone® Battlecross X20 | 110 / 90-19 Dunlop® Geomax MX33 |
DIMENSIONS
| Specification | YZ125 Details | YZ250 Details |
| Length | 84.1 in. | 86.0 in. |
| Height | 51 in. | 50.8 in. |
| Width | 32.5 in. | 32.5 in. |
| Weight | Wet – 209 lb. | Wet – 227 lb. |
| Ground Clearance | Maximum – 14.4 in. | 14.2 in. |
| Wheelbase | 56.9 in. | 58.5 in. |
| Seat Height | 38.6 in. | 38.4 in. |
OPERATIONAL
| Specification | YZ125 Details | YZ250 Details |
| Front Suspension | KYB® Speed-Sensitive System inverted fork; fully adjustable | KYB® single shock; fully adjustable |
| Rear Suspension | KYB® single shock; fully adjustable | KYB® single shock; fully adjustable |
| Front Travel | 11.8 in. | 11.8 in. |
| Rear Travel | 12.4 in. | 12.4 in. |
| Rake | 26° | 27.7° |
| Trail | 4.3 in. | 4.8 in. |
OTHER
| Specification | YZ125 Details | YZ250 Details |
| Manufacturer | Yamaha | Yamaha |
| Model Year | 2024 | 2024 |
| Model | YZ125 50th Anniversary Edition | YZ250 50th Anniversary Edition |
| Model Code | YZ125RSE | YZ250RSE |
| Color | Anniversary White | Anniversary White |
| Price (MSRP) | $7,299 | $8,199 |
Considerations for Both Bikes:
- Size and Weight: Both bikes have similar dimensions, but the YZ125 is generally lighter. Consider the rider’s physical size and strength
- Maintenance: 2-stroke engines require more frequent maintenance compared to 4-strokes. Consider the rider’s willingness and ability to perform regular maintenance.
- Budget: The YZ125 is often more budget-friendly, making it an attractive option for those looking for a cost-effective motocross bike.