2009 Suzuki RM-Z450
General Specifications
| Model | Suzuki RM-Z450 |
| Year | 2009 |
| Category | Motocross |
| Engine Type | 449 cc single-cylinder, four-stroke, DOHC, 4-valve, liquid-cooled |
| Weight | 112 kg curb mass |
Engine
| Displacement | 449 cc |
| Bore x Stroke | 96.0 x 62.1 mm |
| Compression Ratio | 12.2:1 |
| Fuel System | Electronic fuel injection, battery-less system |
| Ignition | Electronic CDI |
| Spark Plug | NGK DIMR8A10 |
| Spark Plug Gap | 0.9-1.0 mm |
| Cooling System | Liquid-cooled |
| Starting System | Primary kick starter with automatic decompression |
Transmission
| Transmission | 5-speed constant-mesh |
| Clutch | Wet multi-plate |
| Final Drive | Chain, 13/50 final gearing |
Dimensions
| Overall Length | 2,185 mm |
| Overall Width | 830 mm |
| Overall Height | 1,260 mm |
| Wheelbase | 1,480 mm |
| Ground Clearance | 350 mm |
| Seat Height | 955 mm |
| Fuel Capacity | 6.2 L |
Chassis
Suspension
| Front Suspension | Showa inverted twin-chamber telescopic fork, coil spring, oil damped, adjustable compression and rebound damping | Fork Oil Levels |
| Front Suspension Travel | 310 mm |
| Rear Suspension | Showa link-type monoshock, coil spring, oil damped, adjustable spring preload and damping |
| Rear Suspension Travel | 310 mm |
| Fork Oil | Suzuki Fork Oil SS-05 or equivalent; 370 ml outer chamber and 193 ml damper chamber per fork leg |
Brakes & Wheels
| Front Brake | Single hydraulic disc, twin-piston caliper |
| Rear Brake | Single hydraulic disc |
| Front Wheel Size | 21 in |
| Rear Wheel Size | 19 in |
Service Data
| Fuel Type | Premium unleaded petrol, minimum 95 RON |
| Premix Information | Not applicable - four-stroke engine with separate engine lubrication |
| Gearbox Oil | Engine and transmission share the same oil; SAE 10W-40, API SF/SG or SH/SJ, JASO MA; 1,050 ml oil change / 1,100 ml with filter / 1,200 ml overhaul |
| Air Filter | Washable polyurethane foam element, oiled with foam air-filter oil |
| Service Notes | Competition four-stroke motocross engine. Check engine oil, air filter, valve clearance, coolant, drive chain, brakes and controls at competition-service intervals. Spark plug torque 11 N·m. |
2009 Suzuki RM-Z450 – Refining Suzuki’s Fuel-Injected 450
The 2009 Suzuki RM-Z450 was primarily a refinement of the major redesign introduced for 2008. Suzuki retained the aluminium twin-spar chassis, five-speed transmission and battery-less electronic fuel injection system that had made the previous RM-Z450 one of the important early fuel-injected production motocross bikes.
Its 449 cc DOHC four-stroke engine continued with a 96.0 x 62.1 mm bore and stroke and a high-performance four-valve cylinder head. Electronic fuel injection removed the carburettor jetting work associated with earlier RM-Z450s and provided more consistent fuel delivery as temperature and riding conditions changed. The 2009 machine remained kick-start only, with an automatic decompression system assisting starting.
Showa suspension was fitted at both ends, with approximately 310 mm of travel front and rear. The inverted twin-chamber fork offered compression and rebound adjustment, while the linkage rear shock provided spring preload and damping adjustment. Owners servicing the front suspension can use the MXOwners fork oil reference when checking oil specifications and setup information.
The 2009 model retained the RM-Z family's strong emphasis on cornering and responsive handling rather than introducing another completely new chassis. For owners rebuilding one today, the MXOwners Parts Finder can help when identifying replacement components, while the MXOwners tyre size guide is useful when checking the standard 21-inch front and 19-inch rear motocross tyre fitment.
