1978 Yamaha HL500 Specifications and Specs
Specifications and workshop reference information for the 1978 Yamaha HL500, 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 | 4-stroke, single-cylinder, air-cooled, SOHC |
| Displacement | 499 cc |
| Bore × Stroke | 87.0 × 84.0 mm |
| Compression Ratio | 8.5:1 |
| Maximum Power | Approx. 38 hp |
| Maximum Torque | 30 to 38 |
| Carburetor | Mikuni VM36 | Replacement Options |
| Lubrication | Dry sump |
| Fuel Mix Ratio | na | Premix Calculator |
| Ignition | Magneto / CDI |
| Starter | Kick start |
| Spark Plug | NGK B8ES |
| Spark Plug Gap | 0.6–0.7 mm |
| Valve Clearance (Intake) | 0.05–0.10 mm |
| Valve Clearance (Exhaust) | 0.10–0.15 mm |
Transmission
| Transmission Type | 5-speed constant mesh |
| Clutch | Wet multi-plate |
| Final Reduction | Chain drive |
Dimensions
| Wheelbase | Approx. 1470 mm |
| Seat Height | Approx. 900 mm |
| Fuel Tank Capacity | Approx. 9.0 L |
| Dry Weight | Approx. 122 kg |
| Bearing Sizes |
Bearing Finder |
Chassis
| Frame Type | Husqvarna-based chrome-moly frame (HL special) |
| Front Suspension | Leading axle telescopic fork | Fork Oil Levels |
| Rear Suspension | Swingarm, twin shock |
| Front Suspension Travel | Approx. 280 mm |
| Rear Suspension Travel | Approx. 300 mm |
Brakes & Wheels
500cc Other Specs
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