1973 Yamaha RT3 360 Specifications and Specs

Specifications and workshop reference information for the 1973 Yamaha RT3-360, 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.

1973 Yamaha RT3-360

General Specifications

Engine TypeAir-cooled 2-stroke single-cylinder
Displacement351cc
Bore × Stroke80.0 × 70.0 mm
Compression Ratio6.9:1
Maximum Power~30 hp
Maximum Torque~38 Nm
CarburetorMikuni VM30 | Replacement Options
LubricationAutolube oil injection
Fuel Mix RatioOil injection (premix optional)
IgnitionBreaker points
Spark PlugNGK B8ES
Spark Plug Gap0.6–0.7 mm

Transmission

Transmission Type6-speed manual
ClutchWet multi-plate
Primary Reduction2.952
Final Reduction3.071
Overall Reduction~9.07 (top gear)

Dimensions

Overall Length~2,150 mm
Overall Width~870 mm
Overall Height~1,160 mm
Wheelbase1,400 mm
Ground Clearance~230 mm
Fuel Tank Capacity~9.5 L
Bearing Sizes Bearing Finder

Chassis

Frame TypeSteel double cradle
Caster Angle~28°
Trail~115 mm
Front SuspensionTelescopic forks | Fork Oil Levels
Rear SuspensionTwin shock swingarm
Front Suspension Travel~180 mm
Rear Suspension Travel~120 mm

Brakes & Wheels

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

360cc Other Specs

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