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Suzuki RM-Z450 2021 Parts & Accessories

Introduced in 2005 as Suzuki's flagship open-class four-stroke motocross racer, the Suzuki RM-Z450 made motorcycle history in 2008 by becoming the first production motocross bike to feature battery-less Electronic Fuel Injection (EFI). Designed for elite MX1 and AMA Supercross competition, the model evolved across several key generations: starting with the original 4-speed carbureted platform (2005–2007), moving to the 5-speed EFI frame redesign (2008–2014), adopting Suzuki Holeshot Assist Control (S-HAC) and Showa SFF-Air suspension in 2015, and undergoing a comprehensive ground-up overhaul in 2018 featuring a new twin-spar frame, Showa coil-spring forks, Showa BFRC rear shock, and sharper bodywork. Celebrated for its razor-sharp cornering, the RM-Z450 remains a benchmark in agile chassis geometry.

• 449 cc liquid-cooled DOHC 4-valve 4-stroke single-cylinder engine with titanium valves, lightweight forged piston, and SCEM cylinder plating
• Power & Torque: ~50 to 56 HP @ 8,500–9,000 RPM and 50 Nm (36.8 lb-ft) torque @ 7,000 RPM
• Induction System: Keihin FCR39 carburetor (2005–2007) evolving to battery-less Keihin Electronic Fuel Injection with 43 mm/44 mm throttle body and plug-in fuel mapping couplers (2008–present)
• Electronics: Suzuki Holeshot Assist Control (S-HAC) multi-mode launch control system and ECM-controlled ignition management
• Chassis Architecture: Twin-spar aluminum alloy frame with removable subframe and aluminum swingarm
• Front Suspension: 47 mm Showa conventional/twin-chamber (2005–2014), Showa SFF-Air TAC (2015–2017), or 49 mm Showa inverted coil-spring forks (2018–present), fully adjustable for compression and rebound damping
• Rear Suspension: Link-type single rear shock absorber (Showa Piggyback / Showa Balance Free Rear Cushion - BFRC), fully adjustable for high/low-speed compression, rebound, and spring preload
• Braking System: Single 250 mm (2005–2017) or 270 mm (2018+) wave-style hydraulic front disc brake with 2-piston caliper and single 240 mm rear hydraulic disc brake
• Transmission & Drivetrain: 4-speed manual (2005–2007) or 5-speed constant-mesh manual transmission (2008–present) with cable-actuated wet multi-plate clutch and 520 chain drive
• Wheels & Tires: 80/100-21 front and 110/90-19 or 120/80-19 rear knobby motocross tires mounted on RK Excel aluminum rims
• Dimensions & Mass: 955 mm to 960 mm (37.6–37.8 in) seat height; dry weight of ~100 kg (220 lbs) (early models) / wet curb weight of 112 kg to 113 kg (247–249 lbs) (modern generation) with a 6.2-litre to 7.2-litre fuel tank capacity