1981 KTM GS390 Specifications and Specs
Specifications and workshop reference information for the 1981 KTM GS390, 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
| Model Year | 1981 |
| Manufacturer | KTM Motor-Fahrzeugbau, Mattighofen, Austria |
| Model | 390 GS |
| Motorcycle Type | Enduro / off-road competition motorcycle |
| Engine Type | Air-cooled, single-cylinder, 2-stroke |
| Engine Capacity | 390 cc class |
| Starting System | Kick start |
| Carburettor | Slide-type carburettor | Replacement Options |
| Lubrication | Premix two-stroke lubrication | Premix Calculator |
| Spark Plug | NGK B8HS |
| Spark Plug Gap | 0.6 mm |
Transmission
| Final Drive | 520 chain |
| Front Sprocket | 13 teeth |
| Rear Sprocket | 48 teeth |
Chassis and Suspension
| Frame Type | Tubular steel enduro frame |
| Swingarm | Aluminium swingarm |
| Front Suspension | 40 mm Marzocchi conventional telescopic forks | Fork Oil Levels |
| Rear Suspension | WP rear suspension | Rear Suspension Setup |
Wheels and Tyres
| Front Wheel | 21-inch spoked wheel |
| Rear Wheel | 18-inch spoked wheel |
| Tyre Fitment | 21-inch front / 18-inch rear | Tyre Size Guide |
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