1980 Kawasaki KDX80
Specifications and workshop reference information for the 1980 Kawasaki KDX80, 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 | 82 cc |
| Bore × Stroke | 48.0 × 45.8 mm |
| Compression Ratio | 7.7:1 |
| Maximum Power | 15 HP @ 11,000 rpm |
| Maximum Torque | 0.98 kg-m @ 10,500 rpm (7.1 ft-lb) |
| Carburetor | Mikuni VM26SS |
| Fuel Type | Petrol mix (20:1) |
| Lubrication | Premix |
| Starting System | Primary kick |
| Ignition | Magneto |
| Ignition Timing | 22° BTDC |
| Spark Plug | NGK B8ES |
Port Timing
| Inlet Open | — |
| Scavenging Open | 64.5° BBDC |
| Scavenging Close | 64.5° ABDC |
| Exhaust Open | 96° BBDC |
| Exhaust Close | 96° ABDC |
Transmission
| Transmission Type | 5-speed constant mesh, return shift |
| Clutch | Wet, multi-disc |
| Final Drive Type | Chain drive |
| 1st Gear | 2.57 (36/14) |
| 2nd Gear | 1.88 (32/17) |
| 3rd Gear | 1.45 (29/20) |
| 4th Gear | 1.17 (27/23) |
| 5th Gear | 1.00 (25/25) |
| Primary Reduction | 3.64 (80/22) |
| Final Reduction | 3.57 (50/14) |
| Overall Drive Ratio | 12.99 (Top gear) |
| Transmission Oil Capacity | 0.6 L (0.63 US qt) |
| Transmission Oil Type | SE class SAE 10W30 or 10W40 |
Dimensions
| Overall Length | 1685 mm (66.3 in) |
| Overall Width | 735 mm (28.9 in) |
| Overall Height | 965 mm (38.0 in) |
| Wheelbase | 1150 mm (45.3 in) |
| Ground Clearance | 230 mm (9.1 in) |
| Dry Weight | 63.5 kg (140 lb) |
| Fuel Tank Capacity | 5.1 L (1.4 US gal) |
Chassis
| Frame Type | Tubular, single down tube |
| Steering Angle | 50° |
| Caster | 26° |
| Trail | 70 mm (2.8 in) |
| Front Tire | 2.75-16 4PR |
| Rear Tire | 3.60-14 4PR |
Suspension
| Front | Telescopic fork |
| Rear | Swing arm |
| Front Suspension Travel | 170 mm (6.7 in) |
| Rear Wheel Travel | 160 mm (6.3 in) |
| Fork Oil Type | SAE 5W20 |
| Fork Oil Capacity | 150 cc (5.1 US oz) |
Brakes & Wheels
| Front Brake | Drum brake |
| Rear Brake | Drum brake |
| Brake Drum Size (Front & Rear) | 100 × 30 mm (3.9 × 1.2 in) |
Community
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