2008 KTM 450SX-F
General Specifications
| Model | KTM 450 SX-F |
| Year | 2008 |
| Category | Motocross |
| Engine Type | Liquid-cooled single-cylinder four-stroke DOHC, 4 valves |
| Weight | Approximately 104.3 kg without fuel |
Engine
| Displacement | 449.3 cc |
| Bore x Stroke | 97.0 x 60.8 mm |
| Compression Ratio | 12.5:1 |
| Fuel System | Keihin FCR-MX 41 mm flat-slide carburettor with accelerator pump | Replacement Options |
| Ignition | Kokusan digital DC-CDI ignition |
| Spark Plug | NGK CR9EKB |
| Spark Plug Gap | 0.70 mm |
| Cooling System | Liquid cooling with mechanically driven water pump |
| Starting System | Electric starter |
Transmission
| Transmission | 4-speed constant-mesh manual |
| Clutch | Wet multi-disc clutch, hydraulically operated |
| Final Drive | Chain |
Dimensions
| Overall Length | |
| Overall Width | |
| Overall Height | |
| Wheelbase | Approximately 1475 mm |
| Ground Clearance | Approximately 380 mm |
| Seat Height | Approximately 985 mm |
| Fuel Capacity | Approximately 8.0 L |
Chassis
Suspension
| Front Suspension | WP 4860 MXMA CC 48 mm upside-down closed-cartridge fork | Fork Oil Levels |
| Front Suspension Travel | 300 mm |
| Rear Suspension | WP 5018 PDS DCC monoshock with linkless Progressive Damping System |
| Rear Suspension Travel | 335 mm |
| Fork Oil | SAE 5 fork oil |
Brakes & Wheels
| Front Brake | 260 mm hydraulic single disc with floating caliper |
| Rear Brake | 220 mm hydraulic single disc with floating caliper |
| 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 |
| Gearbox Oil | Engine and gearbox share lubrication; approximately 1.3 L fully synthetic SAE 10W-50 four-stroke motorcycle oil suitable for wet clutches |
| Air Filter | Washable oiled foam element |
| Service Notes | Competition four-stroke requiring frequent engine-oil and filter changes, air-filter servicing and regular inspection of valve clearance, cam-chain condition, spark plug, clutch, chain, battery and suspension components. |
2008 KTM 450 SX-F: Refining KTM's New-Generation 450
The 2008 KTM 450 SX-F was primarily a refinement of the completely redesigned 2007 machine rather than another new generation. KTM retained the compact 449.3 cc DOHC engine, electric starting, four-speed transmission, chrome-molybdenum frame and linkless WP PDS rear suspension, while concentrating on improving suspension behaviour, engine response and overall race-day refinement.
The engine continued with its 97.0 x 60.8 mm bore and stroke and 12.5:1 compression ratio. Fuel was supplied by a Keihin FCR-MX 41 mm accelerator-pump carburettor, feeding an engine already known for broad, powerful delivery. Owners maintaining an original machine can compare worn or replacement induction components through the MXOwners carburettor reference.
WP suspension remained central to the KTM package. The 48 mm closed-cartridge fork provided 300 mm of travel, while the linkless PDS rear shock offered 335 mm. KTM continued refining damping and chassis balance to make the powerful 450 easier to control over braking bumps and rough acceleration zones. The MXOwners fork oil reference is useful when servicing the original WP front end.
The electric starter remained one of the 450 SX-F's most distinctive features. What had seemed radical only a year earlier was already proving its usefulness for quick restarts after a stall. Historically, the 2008 model represents the consolidation of KTM's modern 450 platform: still carburetted and still using a four-speed gearbox, but already establishing the electric-start, steel-frame and high-spec WP formula that would become central to KTM's motocross identity.
