| MODEL | HONDA NSR 125R 1991 |
| Year | 1991 |
| Engine Type | Two stroke, single cylinder, reed valve induction |
| Displacement / Capacity | 124.8 cc / 7.6 cu in |
| Bore X Stroke | 54 x 54 mm |
| Compression Ratio | 12.0:1 |
| Cooling System | Liquid cooled |
| Max Power | 23.1 kW / 31 hp @ 10500 rpm |
| Max Torque | 20.85 Nm / 15.1 lb-ft @ 9000 rpm |
| Ignition | Capacitor discharge electronic ignition |
| Induction | Dell'Orto PHBH 28 FS carburettor |
| Start System | Electric & kick |
| TRANSMISSION SPECS | |
| Lubrication | — |
| Gear Box | 6 Speed |
| Clutch | Multi-disc oil bath |
| Final Drive | Chain |
| CHASSIS SPECS | |
| Frame | Double cradle tubular steel |
| Front Suspension | 35 mm Marzocchi telescopic forks |
| Rear Suspension | Marzocchi shock, Pro-Link, adjustable preload |
| Front Brakes | Single 316 mm disc, 2 piston caliper |
| Rear Brakes | Single 220 mm disc, 1 piston caliper |
| DIMENSION SPECS | |
| Overall Length | — |
| Overall Width | — |
| Overall Height | — |
| Seat Height | 800 mm / 31.4 in |
| Wheelbase | — |
| Ground Clearance | — |
| Dry Weight | 118 kg / 260 lbs |
| Wet Weight | — |
| WHEEL SPECS | |
| Front Tyre | 100/80-17 |
| Rear Tyre | 130/70-18 |
| FUEL SYSTEM | |
| Fuel Capacity | 10 Litres / 2.6 US gal |
| Fuel Consumption | 18.0 km/lit |
| Top Speed | 164 km/h / 102 mph |
For 1991 the first-generation (JC20) NSR125R continued as Honda's faired Italian two-stroke 125. This was also the year Honda Italia built a limited Sport Production version for the Italian championship, and Japanese sources describe a mid-life update to the JC20 around this time. Day-to-day, the road bike kept its sharp handling and peaky, high-revving character.
