Suzuki RM-Z250 2025 — Specifications

This year will not see a new RM-Z. The motocross department is on hold for development, as are the GSX-R sport models. However, the RM remains in the lineup, relying on its fundamentals. Drawing on Suzuki’s “RIDE. TURN. BRAKE.” philosophy, the factory engineers aimed to make the RM-Z 250 a formidable competitor. The Suzuki has always stood out as one of the most agile 250s on the circuit. Powered by a dual-injector electronic fuel injection system, a central-orifice cylinder head, and a high-performance exhaust system, the RM-Z 250’s engine produces solid, usable power across the entire rev range. To fine-tune engine settings, the MX Tuner 2.0 comes standard.

The aluminum twin-spar frame and hydroformed swingarm carry a suspension supplied by KYB, which includes a coil-spring fork and an adjustable-damping shock absorber with four damping force settings. Powerful brakes and an ergonomic bodywork allow the rider to maintain control of the RM-Z 250 when launching on the circuit.

Faster, higher, stronger.

Motocross is a relentless activity, as are the technology and training needed for the rider and their motorcycle to excel. Suzuki has invested over 40 years of specialized engineering in open-class racing motorcycles into the RM-Z 250, making it the most robust, precise, balanced, and rider-friendly production motocross motorcycle in the company’s history.

Engine Features

- Equipped with a central-orifice cylinder head, the 249 cm³ liquid-cooled, four-valve, DACT and fuel-injected four-stroke engine is designed to be reliable and proven.- This engine offers increased maximum power and excellent throttle response across the entire rev range.- The cylinder head features a refined intake port and finish that precisely tunes the air-fuel mixture in the combustion chamber to increase engine power output.- A large air filter opening is combined with a more direct passage of the air filter outlet tube into the throttle body for high airflow.- The fuel injection system produces very smooth power delivery, highly efficient fuel economy, superb reliability, and easy adjustability.-

Increased Power Across All Revs

- The dual-injector fuel system is used to ensure excellent combustion chamber efficiency and increase high-rev power.- The main fuel injector is located at the bottom of the throttle body and vaporizes fuel at the throttle valve for exceptional fuel and air atomization. The secondary injector is located in the air filter inlet duct so that fuel and air have more time to mix and cool before entering the engine.- The admission camshaft profile features a higher valve lift than the previous generation of the RM-Z 250, increasing power across all revs.- The compact aluminum cylinder is coated with Suzuki’s Electrochemical Coating Method (SCEM) for durability, lightness, and efficient heat transfer.- Engine starting remains simple thanks to a proven electric starter and an automatic decompression system that operates precisely and efficiently (eliminating the need for a heavy and expensive electric starter system).- The high-flow exhaust system features a longer head pipe, a tapered mid section, and a multi-layer muffler, providing good flow across the entire rev range, emphasizing low-end performance.

Electronic System

Traction Control

The RM-Z250 features an advanced and fast traction management system that reacts quickly to changes in engine revs. The electronic control module (ECM) continuously measures throttle opening, engine speed, and gear position, then adjusts ignition timing and fuel injection duration to adjust engine power to provide the best possible traction according to driving conditions. - The RM-Z250’s traction management system differs from that of a road motorcycle, as it does not measure rear wheel slip. Because the needs of a motocross motorcycle differ from those of a road motorcycle, this system provides constant adjustments that maximize traction at all times.Electronic Fuel Injection System AdjustmentSuzuki-proven, easy-to-use fuel couplers are also included to simplify electronic fuel injection system adjustment.- For quick fuel adjustments based on driving conditions, two couplers are provided. One for a richer setting and the other for a leaner fuel setting than the base level. Pilots can change adjustment settings in seconds simply by connecting one or the other coupler to the wiring harness.

Holeshot Start Assistant

The Suzuki Holeshot (S-HAC) electronic start assistant is a mode-selection system derived from the factory racing motorcycle to help the rider get off to a good start from the starting grid.* To help the rider at the start, the S-HAC system offers three stages of power adjustment: 1) initial start moment, 2) grid start exit, and 3) acceleration to full speed.ModesPilots and non-pilots can choose from two S-HAC modes offered depending on their skill level and starting conditions.Mode A: For hard surfaces or slippery conditions at the starting grid. In this mode, the S-HAC system changes ignition timing at the starting grid to reduce rear wheel slip and promote smooth acceleration. It also advances the ignition timing during this sequence for more intense acceleration. After six seconds or when shifting to fourth gear, the ignition timing returns to the standard setting. - Mode B: For surfaces with good traction. In this mode, the S-HAC system advances the ignition timing during the initial acceleration phase to maximize acceleration. - The S-HAC system is turned off when shifting to fourth gear.

Chassis Features- The RM-Z250 features a frame and swingarm that perpetuate Suzuki’s reputation for creating the most agile motocross bikes.- This aluminum twin-spar frame combines cast and extruded sections to achieve superior weight distribution at the front and rear, while balancing strength and weight.- The RM-Z 250 2022 frame is 370 grams lighter, but its torsional rigidity has increased by 10% compared to the frame of the previous generation.- The engine’s location in the frame is tilted upward, so that the crankshaft is higher in the chassis to enrich the motorcycle’s handling characteristics.- The upper engine mounts are located outside the cylinder head to increase rigidity and allow a direct intake path to the engine.

Running Gear

- The engine mount is aluminum, rather than steel, to reduce weight.- The swingarm, which is shaped using an innovative hydroforming process that preserves its strength, weighs only 270 grams.- The KYB shock absorber features a fine-wire spring, a spring guide, a cushioned rubber guide, and a lightweight lower linkage that provide better response to movement. The spring and linkage weigh 447.5 grams less than the parts of the previous generation.- This KYB shock absorber features specialized damping circuits and a refined rear ratio to improve suspension traction.- The KYB high-performance coil-spring front fork features legs with the same springs and damping components, allowing the front suspension to be balanced and maintained easily: a significant advantage when traveling frequently.- This fork uses a free piston that separates air and oil to optimize damping characteristics. The design also helps reduce damper cartridge pressure and spring rebound, so that the fork action remains supple and precise.- The Renthal aluminum tapered handlebar features a flatter curve and a lower pullback than previous models to help the rider maintain control during aggressive maneuvers.- To improve braking performance and feel, a 270 mm diameter wavy-style front brake disc and a two-piston Nissin brake caliper are used.- The wheels feature D.I.D. Dirt Star cross-cut anodized black rims that maintain strength while reducing unsprung weight.- To match the handling potential of the RM-Z 250, the wheels are fitted with Dunlop Geomax MX33 tires developed on race tracks.- Compared to the previous RM-Z 250, the current edition features ergonomic improvements thanks to the new bodywork; the rider’s footrests are moved 3.3 mm forward and 5.2 mm upward, while the handlebar grip location is moved 7.4 mm forward and 3.8 mm downward, to create a high level of rider control during competition.- The plastic fuel tank weighs 226 grams less than the aluminum tank of the previous model. Fuel capacity is 6.3 L.

Credits: Suzuki