In motocross, you’ve got to get instantly hooked up – both out of the gate and off the corners – and also blisteringly fast down the straights. To give riders an even stronger winning balance, the redesigned 2018 RM-Z450 engine has more low-end torque, a flatter overall torque curve, faster and yet more controllable throttle response, and more peak power. Inside the airbox, the air-filter aperture is now 30-percent larger for enhanced airflow, and an MXGP-style mudguard helps keep mud and dirt out, contributing to greater engine durability. The outlet tube leading from the airbox to the fuel-injection throttle body is also straighter, reducing intake resistance for increased power across the rev range.
The fuel-injector spray path now aims fuel upward to hit the throttle butterfly valve directly for improved atomisation. Inside the intake port, the shape is updated for improved tumble flow of the charge as it enters the cylinder, boosting power at all engine speeds. The intake-port shape is matched to a new high-lift intake-cam profile, which further improves intake efficiency and engine output. Inside the combustion chamber, a new piston-rib design adds strength and durability to match the engine’s higher output. While an updated muffler conforms to the latest
Watch any raceday motocross interview, and you’ll invariably hear “get a good start” cited as a must-do proposition. And getting holeshots is exactly what the latest version of the Suzuki Holeshot Assist Control (S-HAC) is all about. An integral part of the electronics package on the latest generation RM-Z range, the updated 3-stage S-HAC system assesses throttle position and gear selection, and then adjusts ignition timing to optimise engine output for fast launches.
The latest version of S-HAC included on the new RM-Z450 gives riders a choice of three settings which can be quickly selected via a handlebar-mounted switch. The “A” mode is programmed for hard surfaces, such as a concrete starting pad, clay or hard-packed dirt where controlling wheelspin is crucial to good starts. For 2018, the “A” mode algorithms are updated to provide even finer control as the throttle is being opened, giving the rider an even better feel for traction in the crucial initial moments of a launch. The “B” mode is for normal dirt conditions. Riders can also select the “Off” setting to retain standard ignition timing.
The new RM-Z450’s electronic systems work seamlessly with the rider to get the power to the ground. To maximise traction for conditions, the engine control module (ECM) automatically adjusts ignition timing and fuel injection based on throttle position, engine speed and gear position. The first RM-Z450 traction management system debuted for 2008, and a revised second -generation system arrived for 2013. Now in the 2018 RM-Z450’s third-generation traction management system, a revised ECU has fully 1.6-times faster data processing and 2.5-times more memory capacity than the first-generation system.
All-new Showa front and rear suspension delivers improved responsiveness and terrain following, enhanced ability to absorb forces, better chassis stability, feedback and terrain feel, and improved comfort. Up front, an updated 49mm Showa coil-spring fork based on works A-type design replaces the SFF-Air fork of the previous-generation RM-Z450. Performance has been increased significantly and offers more consistent feeling throughout a moto. Machine set-up and daily maintenance is also easier for a wide range of riders. The upper triple-clamp is also lighter with optimised dimensions.
The 2018 RM-Z450 is the first production motocross bike to feature the BFRC shock as standard equipment. The new shock shares technology with the all-new 2018 GSX-R1000R sportsbike. The design balances pressure above and below the piston to better control the stroke and smooth out reactions to bumps and chop, even under severe braking.
Riders can adjust the engine performance to suit varied track conditions. By plugging in either of two additional fuel-setting couplers, riders can opt for a richer-than-stock or leaner-than-stock fuel setting to make the most of any riding conditions. Included with the bike, these couplers can be easily plugged in trackside.