1977 KTM GS-6-400
Specifications and workshop reference information for the 1977 KTM GS-6-400, 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 | Air-cooled 2-stroke single-cylinder piston-port |
| Displacement | 397 cc |
| Bore × Stroke | 82.0 mm × 75.0 mm |
| Compression Ratio | 11.0:1 |
| Maximum Power | Approx. 38 hp |
| Maximum Torque | |
| Carburetor | Bing 36 mm |
| Lubrication | Pre-mix |
| Fuel Mix Ratio | 25:1 |
| Ignition | Bosch magneto |
| Spark Plug | Bosch W3CC / NGK equivalent |
| Spark Plug Gap | 0.5 - 0.6 mm |
Transmission
| Transmission Type | 6-speed |
| Clutch | Wet multi-plate |
| Primary Reduction | |
| Final Reduction | Chain drive |
| Overall Reduction | |
Dimensions
| Overall Length | 85.0 in |
| Overall Width | 35.0 in |
| Overall Height | 45.0 in |
| Wheelbase | 57.0 in |
| Ground Clearance | 12.5 in |
| Fuel Tank Capacity | 2.6 gal |
Chassis
| Frame Type | Chrome-moly steel single cradle |
| Caster Angle | |
| Trail | |
| Front Suspension | Telescopic forks |
| Rear Suspension | Dual shock swingarm |
| Front Suspension Travel | 9.8 in |
| Rear Suspension Travel | 4.7 in |
Brakes & Wheels
| Front Tire | 3.00 × 21 |
| Rear Tire | 4.00 × 18 |
| Front Brake | Drum brake |
| Rear Brake | Drum brake |
400cc Other Specs
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