1985 Suzuki RM125 Specifications and Specs

Specifications and workshop reference information for the 1985 Suzuki RM125, 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.

1985 Suzuki RM125 Specifications and Specs

General Specifications

Engine TypeSingle-cylinder, liquid-cooled, piston reed valve, 2-stroke
Displacement123 cc
Bore × Stroke54.0 mm × 54.0 mm
Compression Ratio8.5:1
Maximum Power33 hp @ 10,500 rpm
Maximum Torque21.0 Nm @ 9,500 rpm
CarburetorMikuni 34 mm flat slide | Replacement Options
LubricationPremix
Fuel Mix Ratio20:1 | Premix Calculator
IgnitionSuzuki PEI CDI
Spark PlugNGK BR8ES
Spark Plug Gap0.6 - 0.7 mm

Transmission

Transmission Type6-speed constant mesh
ClutchWet multi-plate
Primary Reduction3.529 (60/17)
Final Reduction3.846 (50/13)
Overall Reduction11.82:1

Dimensions

Overall Length2135 mm
Overall Width815 mm
Overall Height1250 mm
Wheelbase1440 mm
Ground Clearance360 mm
Fuel Tank Capacity7.0 L
Bearing Sizes Bearing Finder

Chassis

Frame TypeChrome-moly steel single-cradle frame
Caster Angle27.5°
Trail115 mm
Front Suspension43 mm Kayaba telescopic forks | Fork Oil Levels
Rear SuspensionSuzuki Full Floater monoshock
Front Suspension Travel300 mm
Rear Suspension Travel300 mm

Brakes & Wheels

Front Tire3.00-21 | Tyre Size Guide
Rear Tire4.50-18 | Tyre Size Guide
Front BrakeSingle leading shoe drum
Rear BrakeSingle leading shoe drum

125cc Other Specs

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