While the DR-Z lineage has remained largely unchanged since 2000, the 2025 Suzuki DR-Z 4S (DRZ4S/25) represents a seismic shift in engineering: it is the first DR-Z to feature a Ride-by-Wire throttle system and a dual-spark cylinder head, finally bringing the legendary 398cc powerplant into the modern era of emissions compliance and precision performance.
| Feature | Specification |
|---|---|
| Model Year | 2025-Present |
| Engine Type | 398cc, 4-stroke, Liquid-cooled, DOHC |
| Lubricant | SAE 10W-40 JASO MA2 API SJ+ |
| Oil Capacity | 1.7 L (Change) / 1.8 L (Filter) |
| Ignition | NGK LMAR8BI-9 (x2) |
| Battery | YTZ10S |
| Front Tire | 80/100-21 M/C 51P (1.25 bar / 18 psi) |
| Rear Tire | 120/80-18 M/C 62P (1.50 bar / 22 psi) |
Technical Review: Engineering the New Era
The DR-Z4S (2025) is not merely a facelift; it is a total mechanical recalibration. At the heart of the machine lies the refined 398cc single-cylinder engine. The transition from the CV carburetor to Electronic Fuel Injection (EFI) has allowed Suzuki engineers to optimize the torque curve, providing a more linear response that dual-sport riders demand. The introduction of the Suzuki Intelligent Ride System (S.I.R.S.), including the Suzuki Drive Mode Selector (SDMS) and a multi-mode Traction Control System, places this bike at the forefront of the middleweight dual-sport category.
Ignition and Combustion
A standout technical highlight is the adoption of a dual-spark ignition system. Utilizing two NGK LMAR8BI-9 iridium plugs, the engine achieves more complete combustion, which not only improves fuel efficiency but also significantly smoothens the power delivery at low RPMs—a critical factor for technical off-road navigation.
Maintenance Guide & Technical Data
For the professional technician and the dedicated owner, adhering to the following specifications is paramount for the longevity of the DRZ4S/25 engine and chassis.
1. Lubrication System
The 2025 model continues to require high-performance synthetic or semi-synthetic oils. The SAE 10W-40 JASO MA2 standard is mandatory to ensure the wet clutch operates without slippage. During a standard oil service, 1.7 liters is required. If the oil filter is replaced—which MotoSpecsLab recommends at every interval—the capacity increases to 1.8 liters.
2. Electrical and Battery
The electrical system is supported by a YTZ10S battery. Given the addition of electronic rider aids and EFI, maintaining a healthy voltage is more critical on this model than its predecessors. Ensure terminals are clean and torqued to prevent intermittent sensor data errors.
3. Chassis and Tires
The DR-Z 4S retains its off-road prowess with a 21-inch front and 18-inch rear wheel configuration. For optimal traction and rim protection, Suzuki specifies a front pressure of 1.25 bar (18 psi) and a rear pressure of 1.50 bar (22 psi). These pressures are optimized for a balance of tarmac stability and off-road compliance.
FAQ
What spark plugs does the 2025 DR-Z 4S use?
The DR-Z 4S uses two NGK LMAR8BI-9 iridium spark plugs to support its dual-spark ignition system.
Is the oil capacity different from the older DR-Z400S?
Yes, while the architecture is similar, always follow the 2025 manual: 1.7L for a change and 1.8L with a filter replacement to ensure the EFI-equipped engine is properly lubricated.
What is the recommended battery for the DRZ4S/25?
The recommended battery is the YTZ10S, which provides the necessary cold cranking amps for the modern starter and electronics suite.