Jointly developed with Kawasaki Heavy Industries, Ltd., the RM-Z250 is Suzuki’s first 4-stroke motocrosser and features a brand new 250 cm³ 4-stroke 1-cylinder DOHC 4-valve engine. Suzuki distilled its technologies and long experience of developing motocross bikes into this engine to achieve highly competitive performance for racing. The engine features widespread use of magnesium, aluminum, and titanium as part of thorough weight-reduction measures. Other weight reduction measures include a slim double main tube frame manufactured from chromium molybdenum steel, a newly designed rear suspension linkage system, as well as specially designed rims and tires. The slimmer chassis also facilitates shifts in rider weight and raises the flexibility of the riding position, both of which are notable features of the RM-Z250.

Both the engine and the chassis of the 2007 RM-Z250 were newly designed. The 250 cm³ 4-stroke liquid-cooled 1-cylinder DOHC 4-valve engine features thoroughly revised combustion chambers to boost torque and to increase power in the mid- to high-rpm range. The chassis uses a lightweight and highly rigid twin-beam aluminum frame. New KYB rear shocks were also adopted to enhance suspension performance.

Following the RM-Z450, the 2010 RM-Z250 adopted a fuel injection system for the first time, resulting in faster throttle response, stronger power characteristics at all rpm ranges, as well as greater acceleration and startability. Three types of fuel injection maps (leaner, normal, richer) can be selected by replacing the provided fuel couplers, allowing the rider to adjust performance for a wide range of courses. In addition, the rigidity balance of parts such as the aluminum frame and swingarm was optimizing, and the suspension updated to further enhance handling and track feel.

The 2019 RM-Z250 realizes enhanced combustion at all rpms through twin injectors and straighter airflows from the air cleaner outlet to the intake port. This model also features a tapered exhaust pipe, higher power in the mid- to high -rpm range, and greater controllability at lower throttle angles. The newly designed frame and swingarm were reduced in weight from the previous model, while retaining at least the same levels of stiffness, helping to enhance rider stability and shock absorption performance. Furthermore, the width between the seat rails was reduced and the shape and hardness of the seat were optimized to facilitate shifts in rider weight and create an even more competitive bike. The exterior design of the RM-Z250 emulates the RM-Z450 that debuted in 2018. Characterized by straight flowing lines from the front fender to the radiator shroud, the result is an impressive sensation of aggression and speed.