1977 Kawasaki KX250
Specifications and workshop reference information for the 1977 Kawasaki KX250, including engine, chassis, service data and setup details.
Note: Specs are compiled from factory data, manuals and owner feedback. Bikes vary — if yours is different, jump into the forum and share it.
General Specifications
| Engine Type | 2-stroke, single-cylinder, piston reed valve |
| Displacement | 249 cc |
| Bore × Stroke | 70 × 64.9 mm |
| Compression Ratio | 7.6:1 |
| Maximum Power | 40 HP @ 6500 rpm |
| Maximum Torque | 3.7 kg-m @ 7000 rpm (26.8 ft-lb) |
| Carburetor | Mikuni VM38SS |
| Fuel Type | Petrol mix (20:1) |
| Lubrication | Premix |
| Starting System | Primary kick |
| Ignition | Electronic CDI |
| Ignition Timing | 20.5° BTDC @ 6000 rpm |
| Spark Plug | NGK B9EV |
| Reed Valve | Boyesen type |
Port Timing
| Inlet Open | — |
| Scavenging Open | 63° BBDC |
| Scavenging Close | 63° ABDC |
| Exhaust Open | 93° BBDC |
| Exhaust Close | 93° ABDC |
Transmission
| Transmission Type | 5-speed constant mesh, return shift |
| Clutch | Wet, multi-disc |
| Final Drive Type | Chain drive |
| 1st Gear | 2.33 (28/12) |
| 2nd Gear | 1.73 (26/15) |
| 3rd Gear | 1.41 (24/17) |
| 4th Gear | 1.16 (22/19) |
| 5th Gear | 1.00 (20/20) |
| Primary Reduction | 2.68 (59/22) |
| Final Reduction | 3.57 (50/14) |
| Overall Drive Ratio | 9.58 (Top gear) |
| Transmission Oil Capacity | 1.0 L (1.1 US qt) |
| Transmission Oil Type | SE class SAE 10W30 or 10W40 |
Dimensions
| Overall Length | 2120 mm (83.5 in) |
| Overall Width | 940 mm (37.0 in) |
| Overall Height | 1185 mm (46.7 in) |
| Wheelbase | 1415 mm (55.7 in) |
| Ground Clearance | 300 mm (11.8 in) |
| Dry Weight | 94 kg (207 lb) |
| Fuel Tank Capacity | 8.0 L (2.1 US gal) |
Chassis
| Frame Type | Tubular, semi-double cradle |
| Steering Angle | 45° |
| Caster | 60° |
| Trail | 130 mm (5.1 in) |
| Front Tire | 3.00-21 4PR |
| Rear Tire | 5.00-18 4PR |
Suspension
| Front | Telescopic fork |
| Rear | Swing arm |
| Front Suspension Travel | 235 mm (9.3 in) |
| Rear Suspension Travel | 135 mm (5.3 in) |
| Fork Oil Type | KYB G-10 or SAE 10W |
| Fork Oil Capacity | 270 cc (9.1 US oz) |
Brakes & Wheels
| Front Brake | Drum brake |
| Rear Brake | Drum brake |
| Front Drum Size | 140 × 28 mm (5.5 × 1.1 in) |
| Rear Drum Size | 150 × 28 mm (5.9 × 1.1 in) |
250cc Other Specs
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