1986 RM125 Manual

The 1986 Suzuki RM125 is a high-performance motocross motorcycle featuring a 124cc two-stroke engine, 6-speed transmission, front and rear suspension systems, and advanced chassis design for competitive racing. Below are key sections covering specifications, maintenance procedures, troubleshooting, and technical data.

1. Specifications 2. Engine Overview 3. Chassis & Suspension 4. Maintenance Schedule 5. Carburetor Adjustment 6. Electrical System 7. Brake System 8. Troubleshooting 9. Torque Specifications 10. Parts Catalog

Specifications

Technical specifications for the 1986 Suzuki RM125 motocross motorcycle.

ComponentSpecification
Engine Type124cc, 2-stroke, single cylinder
Bore x Stroke56.0mm x 50.0mm
Compression Ratio8.5:1
CarburetorMikuni VM32SS
Transmission6-speed constant mesh
Final Drive520 chain
Front SuspensionTelescopic fork, 10.6" travel
Rear SuspensionFull Floater system, 12.2" travel
Front BrakeSingle disc
Rear BrakeSingle drum
Dry Weight192 lbs (87 kg)

Engine Overview

Detailed information about the 124cc two-stroke engine and its components.

  1. Cylinder and piston inspection procedures
  2. Crankcase assembly and disassembly
  3. Reed valve system maintenance
  4. Exhaust system components
  5. Cooling system operation

WARNING! Always allow engine to cool before performing maintenance. Use proper safety equipment.

Chassis & Suspension

Frame geometry and suspension system details.

Maintenance Schedule

Recommended maintenance intervals for optimal performance.

ServiceFrequency
Air Filter CleaningEvery race or 8 hours
Spark Plug ReplacementEvery 15 hours
Piston ReplacementEvery 30 hours
Fork Oil ChangeEvery 40 hours
Transmission OilEvery 10 hours
Chain AdjustmentEvery ride

Carburetor Adjustment

Mikuni VM32SS carburetor tuning procedures.

  1. Float level adjustment: 21mm ± 1mm
  2. Main jet: #260 (standard)
  3. Pilot jet: #40 (standard)
  4. Needle clip position: 3rd groove
  5. Air screw: 1.5 turns out

Tip: Adjust jetting based on altitude and temperature conditions.

Electrical System

Complete electrical system specifications and maintenance.

Brake System

Front disc and rear drum brake maintenance procedures.

  1. Front disc pad replacement procedure
  2. Rear brake shoe inspection
  3. Brake fluid specification: DOT 4
  4. Cable adjustment specifications
  5. Rotor thickness minimum: 3.5mm

Troubleshooting

Common issues and solutions for the 1986 RM125.

SymptomPossible CauseCorrective Action
Hard startingFouled plug, improper jettingReplace spark plug, check carburetor settings
Poor performanceClogged air filter, worn pistonClean air filter, inspect piston and cylinder
Transmission issuesWorn gears, improper oil levelCheck transmission oil, inspect gear teeth
Suspension problemsLeaking seals, improper dampingReplace fork seals, adjust damping settings
Brake fadeContaminated pads, worn shoesReplace brake components, clean rotors

Torque Specifications

Critical torque values for engine and chassis components.

ComponentTorque Value
Cylinder Head Nuts20 Nm (14.5 ft-lbs)
Spark Plug25 Nm (18 ft-lbs)
Front Axle Nut65 Nm (47 ft-lbs)
Rear Axle Nut90 Nm (65 ft-lbs)
Sprocket Nuts45 Nm (32.5 ft-lbs)

Parts Catalog

Genuine Suzuki parts reference and ordering information.

Service: Contact authorized Suzuki dealers for genuine parts.

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