| Quick Specs: Yamaha WR 125 R (22BB/15) | |
|---|---|
| Production Years | 2009 – 2017 |
| Engine Oil | SAE 10W-40 API SG+, JASO MA (1.0 L) |
| Tires (F/R) | 80/90-21 / 110/80-18 |
| Tire Pressure | 2.0 bar (29 psi) Front & Rear |
| Battery | YTZ7S |
| Spark Plug | NGK CR9E |
While many 125cc motorcycles are built as entry-level commuters, the Yamaha WR 125 R was engineered with a unique pedigree: it utilizes a liquid-cooled, 4-valve fuel-injected engine that shares its core architecture with the high-performance YZF-R125. This made it one of the most technologically advanced dual-sports in its class during its production run from 2009 to 2017, offering a high-revving character rarely seen in the learner-legal segment.
Engineering Overview
The 22BB/15 designation refers to the specific internal model coding for this robust dual-sport. Unlike its supermoto sibling (the WR 125 X), the ‘R’ variant features a 21-inch front wheel and an 18-inch rear, adhering to traditional enduro dimensions. This allows for superior obstacle roll-over and access to a wide variety of off-road oriented rubber. The steel semi-double-cradle frame provides the necessary rigidity for light trail use while maintaining enough flex to absorb vibrations from the single-cylinder powerplant.
Maintenance Essentials
To maintain the E-E-A-T standards of MotoSpecsLab, we emphasize following the manufacturer’s strict lubrication and electrical requirements:
- Lubrication: The engine requires exactly 1.0 liter of 10W-40 oil. It is critical to ensure the oil meets JASO MA standards to prevent clutch slippage, as the WR 125 R uses a wet multi-plate clutch system.
- Ignition: The NGK CR9E spark plug is essential for maintaining the correct heat range. A fouled or incorrect plug can lead to poor fuel atomization and starting issues in cold weather.
- Electrical: The YTZ7S battery is a compact, high-output AGM unit. Given the fuel injection system’s reliance on stable voltage, maintaining a healthy battery is paramount for reliable ECU operation.
Chassis and Handling
With a seat height of 930mm, the WR 125 R is a tall machine, providing excellent ground clearance for off-road excursions. The suspension consists of 41mm conventional forks and a Monocross rear link, which are tuned for a balance between road comfort and trail damping. Tire pressures should be kept at 2.0 bar (29 psi) for general road use, though experienced riders may drop these slightly for increased traction on loose soil.
Frequently Asked Questions
What is the oil capacity of the WR 125 R?
The total oil capacity for a standard change is 1.0 Liter of SAE 10W-40 (JASO MA).
Which spark plug does the 22BB/15 model use?
The recommended spark plug is the NGK CR9E.
What are the factory tire sizes?
The front uses an 80/90-21 M/C 48P, and the rear uses a 110/80-18 M/C 58P.