1979 Yamaha YZ80 Specifications and Specs
Specifications and workshop reference information for the 1979 Yamaha YZ80, 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 | Single-cylinder, two-stroke, air-cooled, reed valve |
| Displacement | 79 cc |
| Bore × Stroke | 49.0 × 42.0 mm |
| Compression Ratio | 7.2:1 |
| Maximum Power | Not Published |
| Maximum Torque | Not Published |
| Carburetor | Mikuni VM26SS | Replacement Options |
| Lubrication | Premix |
| Fuel Mix Ratio | 20:1 | Premix Calculator |
| Ignition | CDI magneto |
| Spark Plug | NGK B9ES |
| Spark Plug Gap | 0.5 – 0.6 mm |
Transmission
| Transmission Type | 6-speed constant mesh |
| Clutch | Wet multi-plate |
| Primary Reduction | 3.578 |
| Final Reduction | Not Published |
| Overall Reduction | Not Published |
Dimensions
| Overall Length | 1,715 mm |
| Overall Width | 760 mm |
| Overall Height | 965 mm |
| Wheelbase | 1,180 mm |
| Ground Clearance | 200 mm |
| Fuel Tank Capacity | 4.5 L |
| Bearing Sizes |
Bearing Finder |
Chassis
| Frame Type | Steel tubular single cradle |
| Caster Angle | Not Published |
| Trail | Not Published |
| Front Suspension | Telescopic forks | Fork Oil Levels |
| Rear Suspension | Monocross single shock swingarm | Rear Suspension Setup |
| Front Suspension Travel | 165 mm |
| Rear Suspension Travel | 155 mm |
Brakes & Wheels
Service Data
| Spark Plug | NGK B9ES |
| Transmission Oil Capacity | 750 ml |
| Starting System | Kick start |
| Dry Weight | Approximately 62 kg |
| Chain Type | 428 |
80cc Other Specs
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