1983 KTM 250MX Specifications and Specs

Specifications and workshop reference information for the 1983 KTM 250MX, 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.

1983 KTM 250MX

General Specifications

Engine TypeSingle-cylinder, two-stroke, reed valve
Displacement244 cc
Bore × Stroke70 × 64 mm
Compression RatioApprox. 13.5:1
Maximum Power~38 hp
Maximum Torque
CarburetorBing 36 mm | Replacement Options
LubricationPremix
Fuel Mix Ratio40:1 | Premix Calculator
IgnitionMotoplat
Spark PlugNGK equivalent
Spark Plug Gap0.5 – 0.6 mm

Transmission

Transmission Type5-speed constant mesh
ClutchWet multi-plate

Dimensions

Wheelbase1470 mm
Fuel Tank Capacity9–11 L
Bearing Sizes Bearing Finder

Chassis

Frame TypeSteel, single shock (Pro-Lever)
Front SuspensionMarzocchi telescopic forks | Fork Oil Levels
Rear SuspensionPro-Lever single shock (WP/Fox)
Front Suspension Travel300 mm
Rear Suspension Travel320 mm

Brakes & Wheels

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

250cc Other Specs

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