| MODEL | HONDA XR 500R 1981 |
| Year | 1981 |
| Engine Type | Four stroke, single cylinder, SOHC, 4 valve |
| Displacement / Capacity | 497 cc / 30.3 cu in |
| Bore X Stroke | 89 x 80 mm |
| Compression Ratio | 8.6:1 |
| Cooling System | Air cooled |
| Max Power | 26.3 kW / 36 hp @ 6500 rpm |
| Max Torque | 41.4 Nm / 4.2 kgf-m / 30 lb-ft @ 5500 rpm |
| Ignition | CDI |
| Induction | Single 34 mm / 1.34 in piston valve Keihin carburettor |
| Start System | Kick |
| TRANSMISSION SPECS | |
| Lubrication | — |
| Gear Box | 5 Speed |
| Clutch | Wet plate |
| Final Drive | Chain |
| CHASSIS SPECS | |
| Frame | Welded tubular steel |
| Front Suspension | 37 mm Showa forks, 224 mm / 8.8 in travel |
| Rear Suspension | Pro-Link single Showa damper, adjustable spring preload and rebound damping, 198 mm / 7.8 in travel |
| Front Brakes | 140 mm drum |
| Rear Brakes | 130 mm drum |
| DIMENSION SPECS | |
| Overall Length | 2210 mm / 87.0 in |
| Overall Width | 875 mm / 34.4 in |
| Overall Height | 1215 mm / 47.8 in |
| Seat Height | 880 mm / 34.6 in |
| Wheelbase | 1400 mm / 55.1 in |
| Ground Clearance | 280 mm / 11.0 in |
| Dry Weight | 123 kg / 271.2 lbs |
| Wet Weight | 137 kg / 302.0 lbs |
| WHEEL SPECS | |
| Front Tyre | 3.00-21 |
| Rear Tyre | 4.10-17 |
| FUEL SYSTEM | |
| Fuel Capacity | 12 Litres / 3.1 US gal |
| Fuel Consumption | — |
| Top Speed | 148.5 km/h / 92.2 mph |
Photo: Sssjej, CC BY-SA 3.0, via Wikimedia Commons
Photo: MadYax, CC BY-SA 3.0, via Wikimedia Commons
For 1981 the XR500 became the XR500R, swapping its twin shocks for Honda's rising-rate Pro-Link single-shock rear end and moving to 21-inch front and 17-inch rear wheels. A six-petal reed valve was added to the intake and the seat and airbox were redesigned. Testers saw it as a capable trail and play bike that could also do enduro duty, though it lacked top-end punch.
