2005 Kawasaki KX250F
General Specifications
| Model | Kawasaki KX250F |
| Year | 2005 |
| Category | Motocross |
| Engine Type | 249 cc single-cylinder, four-stroke, DOHC, 4-valve, liquid-cooled |
| Weight | Approximately 93 kg dry |
Engine
| Displacement | 249 cc |
| Bore x Stroke | 77.0 x 53.6 mm |
| Compression Ratio | 12.6:1 |
| Fuel System | Keihin FCR 37 mm flat-slide carburettor | Replacement Options |
| Ignition | Digital CDI |
| Spark Plug | NGK CR8E |
| Spark Plug Gap | 0.7-0.8 mm |
| Cooling System | Liquid-cooled |
| Starting System | Primary kick starter with automatic decompression |
Transmission
| Transmission | 5-speed constant-mesh, return shift |
| Clutch | Wet multi-disc |
| Final Drive | Chain, 520 size |
Dimensions
| Overall Length | Approximately 2,175 mm |
| Overall Width | Approximately 820 mm |
| Overall Height | Approximately 1,275 mm |
| Wheelbase | Approximately 1,475 mm |
| Ground Clearance | Approximately 345 mm |
| Seat Height | Approximately 965 mm |
| Fuel Capacity | Approximately 7.5 L |
Chassis
| Frame | High-tensile steel perimeter motocross frame with aluminium swingarm |
| Front Tyre | 80/100-21 51M | Tyre Size Guide |
| Rear Tyre | 100/90-19 57M | Tyre Size Guide |
Suspension
| Front Suspension | 48 mm Kayaba inverted cartridge fork, adjustable compression and rebound damping | Fork Oil Levels |
| Front Suspension Travel | Approximately 300 mm |
| Rear Suspension | Uni-Trak linkage with Kayaba gas-charged shock, adjustable spring preload, compression and rebound damping |
| Rear Suspension Travel | Approximately 310 mm |
| Fork Oil | Kayaba 01 / KHL15-10 or equivalent high-performance fork oil |
Brakes & Wheels
| Front Brake | Single hydraulic disc |
| Rear Brake | Single hydraulic disc |
| Front Wheel Size | 21 x 1.60 in |
| Rear Wheel Size | 19 x 1.85 in |
Service Data
| Fuel Type | Premium unleaded petrol |
| Premix Information | Not applicable - four-stroke engine with separate engine lubrication |
| Gearbox Oil | Engine and transmission share the same oil; SAE 10W-40 motorcycle oil meeting API SG/SH/SJ and JASO MA specification |
| Air Filter | Washable oiled polyurethane foam element |
| Service Notes | Competition four-stroke motocross engine. Check engine oil frequently and inspect valve clearance, air filter, coolant, drive chain, brakes and controls at short competition-service intervals. |
2005 Kawasaki KX250F – Refining Kawasaki’s First 250 Four-Stroke
The 2005 Kawasaki KX250F was a refinement of the first-generation 2004 machine rather than a completely new model. Kawasaki retained the basic steel perimeter frame, 249 cc DOHC four-stroke engine and Keihin FCR carburettor developed through its joint 250 four-stroke program with Suzuki, while concentrating on detail improvements aimed at reliability and race performance.
The engine kept its 77.0 x 53.6 mm bore and stroke and high 12.6:1 compression ratio. A four-valve cylinder head and high-revving short-stroke layout gave the KX250F the performance needed to compete in the rapidly expanding 250 four-stroke class. Fuel continued to be supplied by a 37 mm Keihin FCR flat-slide carburettor, so jetting and accelerator-pump setup remained important tuning areas. Owners repairing an incomplete induction system can compare replacement carburettor options.
The 2005 chassis remained based around Kawasaki’s steel perimeter frame, with Kayaba suspension and Uni-Trak rear linkage. The inverted front fork offered adjustable compression and rebound damping, while the rear shock provided preload and damping adjustment. Owners servicing the front end can use the MXOwners fork oil reference when checking suitable suspension fluid and setup information.
Historically, the 2005 KX250F represents Kawasaki settling into the new four-stroke era while the KX250 two-stroke was still being sold alongside it. The KX250F required a different maintenance routine, with regular engine-oil changes, valve-clearance checks and careful air-filter servicing replacing the premix routine familiar to two-stroke riders. Owners restoring one today can use the MXOwners Parts Finder when checking replacement components.
