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.... The RM125 also got the fine-tooth comb treatment. The motor is said to be stronger from midrange on up. Nothing too drastic here, but the '04 RM250 twostroke took on numerous refinements to both the engine and chassis. What Suzuki Says••• What Was Done and Wh New-style front brake master cylinder features an advanced piston seal design for improved brake lever feel and permits simplified hose routing and a shorter brake hose. Floating front brake rotor for more consistent brake performance and reduced drag. Simplified rear brake master cylinder with built-in reservoir - reduces weight by eliminating brackets required for separate reservoir and hose. More compact swingarm-mounted rear brake caliper bracket. Improved rear brake caliper piston seal design for reduced drag, plus improved brake pad retainers to prevent mud buildup between pads and retainers. RM125 Refined power characteristics with emphasis on mid-to-high rpm performance. New cylinder head with redesigned combustion chamber to improve mid-to-high rpm power. A flat-top piston design is lighter in weight to reduce reciprocating mass and improve engine response, plus blends with cylinder head design to improve combustion chamber shape. New subexhaust port system and elimination of exhaust port bridge help improve power and acceleration feel at mid-to-high rpm. Redesigned exhaust valve system operates main and subexhaust port valves, improving power output at all engine speeds. More durable steel bushings between exhaust valve actuator and exhaust valve rod. Reshaped boost scavenging ports for improved mid-ta-high rpm performance. Longer connecting rod and increased crankshaft inertia improve rear-wheel traction, power control and high rpm rev capability. New air filter with larger mesh size improves airflow to the engine for better power and throttle response. Redesigned shift cam stopper system features a reshaped stopper plate, more rigid stopper arm and high spring rate for more precise gear shift operation and improved shifting feel. Improved riding position with 1Omm-Iower seat position, allowing the rider greater freedom of movement. Improved front fork performance with the following changes: reshaped oil separator with straighter oil passage, standard-style low-speed compression valves, increased diameter of the lower section outer fork tube. Improved rear shock performance with the following changes: standard-style low-speed compression valves, elimination of piston check valves, redesigned lower clevis mount. New rear shock linkage system designed for more progressive rear shock performance; cushion lever is now connected to the swingarm and the link rods to the frame. New-style front brake master cylinder features an advanced piston seal design for improved brake lever feel and permits simplified hose routing and a shorter brake hose. Floating front brake rotor for more consistent brake performance and reduced drag. Simplified rear brake master cylinder with built-in reservoir - reduces weight by eHminating brackets required for separate reservoir and hose. More compact swingarm-mounted rear brake caliper bracket. Improved rear caliper piston seal design for reduced brake drag, plus new brake pad retainers designed to prevent mud buildup. RM250 Retuned engine for improved overall power and torque. especially at high rpm. New cylinder head with reduced squish height for better low-to-midrange throttle response. Reshaped subexhaust ports for better mid-to-high rpm power delivery. Redesigned subexhaust port control rods and cams for optimum subexhaust port valve operation and improved power delivery. Increased crankshaft inertia for better rear-wheel traction control and acceleration feel. New barrel-type piston rings for improved low rpm engine response. Increased exhaust valve governor spring rate for optimum exhaust valve control and power delivery. Refined carburetor settings with new jet needle, throttle valve and power jet for increased lowrpm throttle response. New air filter with larger mesh size improves airflow to the engine for better power and throttle response. Redesigned shift cam stopper system features a reshaped stopper plate, more rigid stopper arm and higher spring rate for more precise gear shift operation and improved shifting feel. Improved riding position with 10mm-lower seat, footpegs moved back IOOmm, handlebars raised 7mm, allowing the rider greater freedom of movement. Increased frame reinforcement to improve rigidity and straight-line performance. New Showa twin-chamber front forks and Showa rear shock absorber (similar design as RMI25). New rear shock linkage system for more progressive performance; cushion lever now connects to the swingarm and the Hnk rods to the frame. RM-Z250 Compact 249cc, four-stroke. liquid-cooled, DOHC, four-valve engine - designed for easy-toride four-stroke power with optimum balance of crank inertia and engine brake performance (no counterbalancer system required). Advanced four-valve cylinder head design with narrow 25-degree included valve angle and titanium valves (31mm intake, 25mm exhaust) create a compact combustion chamber for high combustion efficiency. Cam profiles selected for a wide powerband with strong peak power - camshafts are carburized for durability and operate steel alloy valve tappets. Plated aluminum alloy cylinder for increased durability, optimum engine cooling and operating temperature. Forged, two-ring piston designed for maximum oil retention and minimal wear, plus tin plating for added durability. Keihin FCR37 carburetor with throttle position sensor and accelerator pump for increased throttle response, plus a hot start circuit for quick engine restarts. Automatic decompression system for easy kick starting - simple, lightweight and designed for reliable operation, plus optional cable setup for manual operation. Semi-dry-sump lubrication system features separate oil chambers for the transmission and crankshaft using the transmission as the oil sump, allowing low crankshaft placement, reduced engine height and a low center of gravity. Intemal reed-valve between oil chambers relieves pressure from the crank chamber to reduce mechanical loss and improve high-rev performance. Internal oil passageways to the top-end eliminate the weight and complexity of extemal oil lines. AC-CDI ignition system with two ignition maps automatically increases engine idle speed to reduce engine brake effect. Five-speed transmission featuring a ratchet-type shift mechanism designed for light shifting effort, plus compensates for differences in shift force used by different riders. Thin-walled crankcase construction and magnesium valve, generator and outer clutch covers minimize overall engine weight. One-piece water pump and oil filter cover helps minimize engine size and weight. Lightweight exhaust system features a titanium and stainless steel construction, plus a repackable aluminum/stainless steel muffler. Aluminum skid plate with plastic side guards and aluminum engine mounting plates. Lightweight twin-spar frame with D-shaped upper spars that contribute to a slim design and improved position and rider mobility. Slim new bodywork allows greater freedom of movement for the rider, and includes a 7.5-liter fuel tank, flat-shape seat with slip-resistant cover, long rear fender, narrow radiator shrouds and right-side cover with built-in exhaust heat shield. Aluminum triple clamps with rigid handlebar-mount and tapered steering stem provide for minimal weight. New Kayaba 48mm inverted, bladder-style front fork has a special valve system to optimize internal pressure and damping performance throughout the stroke - includes compact axle brackets and fork tube guards. Kayaba reservoir-type rear shock absorber - includes drain bolt for shock oil replacement and upper shock mount positioned for easy access to the carburetor. New rear linkage system (similar to the RMI25/250) places the suspension load on the swingarm instead of the frame to reduce frame weight and allows smoother movement of the rear shock and linkage for improved rear-wheel traction. Aluminum swingarm with tapered hydro-formed beams, forged axle holder, plus cast and forged linkage components - all designed for strength and minimal weight. Front disc brake system consists of a dual-piston caliper with 27mm pistons, master cylinder with large, II mm piston and thin Kevlar brake line for reduced weight and progressive brake feel. Lightweight rear brake system includes a dual piston caliper with 25.4mm pistons and durable forged brake pedal. eye I e nevvs JUNE 18, 2003 57