1981 Honda xr500
Specifications, manuals and workshop reference information.
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 | Air-cooled 4-stroke single, OHC |
| Displacement | 497 cc |
| Bore x Stroke | 89.0 mm x 80.0 mm |
| Compression Ratio | 8.6 : 1 |
| Valve Train | Chain-driven overhead camshaft |
| Carburetor | Keihin PD11B piston valve |
| Transmission | 5-speed |
| Clutch | Wet multi-plate |
| Final Drive | Chain |
| Maximum Power | 43 hp @ 6300 rpm |
| Maximum Torque | 4.3 kg-m @ 3000 rpm |
Dimensions
| Overall Length | 2160 mm |
| Overall Width | 850 mm |
| Overall Height | 1235 mm |
| Wheelbase | 1420 mm |
| Ground Clearance | 320 mm |
| Seat Height | 875 mm |
| Dry Weight | 126 kg |
Chassis
| Frame Type | Diamond |
| Front Suspension | Telescopic fork, air-adjustable |
| Rear Suspension | Pro-Link |
| Front Brake | Internal expanding shoe |
| Rear Brake | Internal expanding shoe |
| Fuel Capacity | 9 L |
| Fuel Reserve | 3 L |
| Fork Oil Capacity | 345 cc each leg |
| Trail | 112 mm |
| Caster | 62° |
Service Specifications
| Engine Oil Capacity | 2.0 L (disassembly), 1.7 L (oil change) |
| Recommended Oil | API SE, SAE 10W-40 |
| Spark Plug | NGK D8EA / ND X24ES-U |
| Spark Plug Gap | 0.6-0.7 mm |
| Valve Clearance (Inlet) | 0.05 mm |
| Valve Clearance (Exhaust) | 0.10 mm |
| Idle Speed | 1200 ± 100 rpm |
| Compression Pressure | 12.5 ± 1.5 kg/cm² (177 ± 21 psi) |
Ignition & Carburetor
| Ignition | CDI |
| Ignition Timing (Initial) | 10° BTDC @ 2260 rpm |
| Ignition Timing (Full Advance) | 36° ± 2° BTDC @ 3500 rpm |
| Main Jet | #152 |
| Pilot Jet | #67 |
| Pilot Screw | 2 1/4 turns out |
| Float Level | 14.5 mm |
Wheels & Tyres
| Front Tyre | 3.00-21 |
| Rear Tyre | 5.10-17 |
| Front Tyre Pressure | 14 psi |
| Rear Tyre Pressure | 11 psi |
| Minimum Tread Depth | 8 mm |
| Front Rim Size | 1.60 x 21 |
| Rear Rim Size | 2.15 x 17 |
Transmission Ratios
| Primary Reduction | 2.379 |
| 1st Gear | 2.462 |
| 2nd Gear | 1.647 |
| 3rd Gear | 1.200 |
| 4th Gear | 1.000 |
| 5th Gear | 0.840 |
| Final Reduction | 3.000 (39/13) |
| Shift Pattern | 1-N-2-3-4-5 |
| Drive Chain | RK520KO, 105 links |
500cc Other Specs
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