1979 Yamaha YZ250 Specifications and Specs
Specifications and workshop reference information for the 1979 Yamaha YZ250, 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.
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General Specifications
Engine Type Air-cooled 2-stroke single-cylinder reed valve
Displacement 246 cc
Bore × Stroke 70.0 × 64.0 mm
Compression Ratio 6.8:1
Maximum Power
Maximum Torque
Carburetor Mikuni VM38SS
Lubrication Premix
Fuel Mix Ratio 20:1
Ignition CDI Magneto
Spark Plug NGK B8ES
Spark Plug Gap 0.6 - 0.7 mm
Transmission
Transmission Type 5-speed constant mesh
Clutch Wet multi-plate
Primary Reduction 3.000
Final Reduction Chain drive
Overall Reduction
Dimensions
Overall Length 2170 mm
Overall Width 820 mm
Overall Height 1240 mm
Wheelbase 1490 mm
Ground Clearance 300 mm
Fuel Tank Capacity 10.0 L
Chassis
Frame Type Steel single backbone
Caster Angle 28°
Trail
Front Suspension Telescopic forks
Rear Suspension Monocross single shock
Front Suspension Travel 280 mm
Rear Suspension Travel 295 mm
Brakes & Wheels
Front Tire 3.00-21
Rear Tire 4.50-18
Front Brake Drum
Rear Brake Drum
250cc Other Specs
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