| Specification | Data |
|---|---|
| Production Years | 2009 – 2017 |
| Engine Oil | SAE 10W-40 API SG/JASO MA (1.0 L) |
| Front Tire | 80/90-21 M/C 48P |
| Rear Tire | 110/80-18 M/C 58P |
| Tire Pressure | 2.0 bar (29 psi) Front/Rear |
| Battery | YTZ7S |
| Spark Plug | NGK CR9E |
Engineering Highlight: The Yamaha WR 125 R (DE071) is notable for utilizing a high-compression, liquid-cooled, 4-valve SOHC engine architecture directly derived from the YZF-R125. This made it one of the first 125cc dual-sport motorcycles to feature a sophisticated electronic fuel injection (EFI) system, offering linear power delivery and exceptional reliability compared to its carbureted contemporaries.
Technical Overview
The DE071 chassis was engineered to bridge the gap between a commuter and a weekend trail-blazer. With its 21-inch front wheel and 18-inch rear, it adheres to full-size enduro geometry, providing a seat height and ground clearance that command respect in the A1 category. The fuel-injected single-cylinder engine is renowned for its durability, provided the strict maintenance schedule for its 1.0-liter oil capacity is observed.
Maintenance Guide
Engine Lubrication
For the WR 125 R, oil quality is paramount due to the high-revving nature of the 4-valve head. Use 1.0 Liter of SAE 10W-40 meeting API SG and JASO MA standards. The JASO MA certification is critical to ensure the wet clutch does not slip under load.
Ignition and Electrical
The NGK CR9E spark plug is the factory-specified heat range for this engine. Checking the gap and color of the plug is essential for monitoring the health of the EFI system. For starting reliability, the YTZ7S battery provides the necessary cold cranking amps (CCA) in a compact form factor.
Tires and Chassis
The DE071 uses a traditional enduro wheel setup. The front 80/90-21 and rear 110/80-18 should be maintained at 2.0 bar (29 psi) for mixed-use riding. Lowering pressures for off-road use is common, but for street-legal operation and rim protection, the factory 2.0 bar recommendation is the baseline for stability.
Expert Verdict
The Yamaha WR 125 R remains a benchmark for the 125cc dual-sport class. Its robust build quality and high-specification engine make it a favorite for riders seeking a “big bike” feel in a learner-legal package. Regular maintenance of the cooling system and oil levels is the key to achieving the legendary longevity these Yamaha singles are known for.