1976 Yamaha YZ400 Specifications and Specs

Specifications and workshop reference information for the 1976 Yamaha YZ400, 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.

1976 Yamaha YZ400

General Specifications

Engine TypeAir-cooled, single-cylinder, 2-stroke
Displacement397 cc
Bore × Stroke83.0 × 72.0 mm
Compression RatioApprox. 7.0:1
Maximum PowerApprox. 40 hp
Maximum TorqueN/A
CarburetorMikuni VM38SS | Replacement Options
LubricationPremix
Fuel Mix Ratio20:1 – 32:1 | Premix Calculator
IgnitionCDI (magneto)
Spark PlugNGK B8ES
Spark Plug Gap0.6 – 0.7 mm

Transmission

Transmission Type5-speed manual
ClutchWet multi-plate
Primary Reduction2.863
Final Reduction3.000
Overall ReductionN/A

Dimensions

Overall Length2,180 mm
Overall Width850 mm
Overall Height1,220 mm
Wheelbase1,450 mm
Ground Clearance250 mm
Fuel Tank Capacity9.0 L
Bearing Sizes Bearing Finder

Chassis

Frame TypeSteel single cradle
Caster AngleApprox. 27°
TrailN/A
Front SuspensionTelescopic forks | Fork Oil Levels
Rear SuspensionTwin shock swingarm
Front Suspension Travel~200 mm
Rear Suspension Travel~100 mm

Brakes & Wheels

Front Tire3.00-21 | Tyre Size Guide
Rear Tire4.50-18 | Tyre Size Guide
Front BrakeDrum
Rear BrakeDrum

400cc Other Specs

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