1977 KTM GS 6 400 Specifications and Specs

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.

1977 KTM GS-6-400

General Specifications

Engine TypeAir-cooled 2-stroke single-cylinder piston-port
Displacement397 cc
Bore × Stroke82.0 mm × 75.0 mm
Compression Ratio11.0:1
Maximum PowerApprox. 38 hp
Maximum Torque
CarburetorBing 36 mm | Replacement Options
LubricationPre-mix
Fuel Mix Ratio25:1 | Premix Calculator
IgnitionBosch magneto
Spark PlugBosch W3CC / NGK equivalent
Spark Plug Gap0.5 - 0.6 mm

Transmission

Transmission Type6-speed
ClutchWet multi-plate
Final ReductionChain drive

Dimensions

Overall Length85.0 in
Overall Width35.0 in
Overall Height45.0 in
Wheelbase57.0 in
Ground Clearance12.5 in
Fuel Tank Capacity2.6 gal
Bearing Sizes Bearing Finder

Chassis

Frame TypeChrome-moly steel single cradle
Front SuspensionTelescopic forks | Fork Oil Levels
Rear SuspensionDual shock swingarm
Front Suspension Travel9.8 in
Rear Suspension Travel4.7 in

Brakes & Wheels

Front Tire3.00 × 21 | Tyre Size Guide
Rear Tire4.00 × 18 | Tyre Size Guide
Front BrakeDrum brake
Rear BrakeDrum brake

400cc Other Specs

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