1986 Suzuki GSXR 750 Service Manual

The 1986 Suzuki GSXR 750 is a revolutionary sport bike featuring a 749cc liquid-cooled four-cylinder engine, aluminum frame, full fairing, and advanced suspension components. This service manual covers maintenance procedures, specifications, troubleshooting, and repair instructions for the complete motorcycle system including engine, transmission, chassis, electrical, and fuel systems.

1. General Information 2. Specifications 3. Maintenance Schedule 4. Engine Service 5. Fuel System 6. Electrical System 7. Chassis & Suspension 8. Brake System 9. Troubleshooting 10. Wiring Diagrams 11. Torque Specifications

General Information

This manual provides detailed service information for the 1986 Suzuki GSXR 750. Includes safety precautions, tool requirements, and general maintenance procedures.

Component	Description
Model	GSXR750
Year	1986
Engine Type	4-stroke, liquid-cooled, DOHC
Displacement	749cc
Frame	Aluminum box section
Front Suspension	41mm telescopic fork
Rear Suspension	Full-floater swingarm
Brakes	Dual disc front, single disc rear
Weight	426 lbs (dry)
Fuel Capacity	5.3 gallons

Specifications

Engine: 749cc, 4-cylinder, liquid-cooled, DOHC, 16-valve
Bore x Stroke: 70.0 x 48.7 mm
Compression Ratio: 10.5:1
Carburetion: 4x Mikuni BST31SS
Ignition: Transistorized electronic
Transmission: 6-speed constant mesh
Final Drive: #530 chain
Front Tire: 120/80V16
Rear Tire: 140/80V18
Wheelbase: 56.7 inches

Maintenance Schedule

Regular maintenance intervals for optimal performance and longevity.

Every 600 miles: Check/adjust chain, check tire pressure, inspect brakes
Every 3,000 miles: Change engine oil and filter
Every 6,000 miles: Clean/lube cables, check valve clearance
Every 12,000 miles: Replace spark plugs, clean air filter
Every 2 years: Replace brake fluid, coolant replacement

WARNING! Always use genuine Suzuki parts for replacement. Follow all safety procedures.

Engine Service

Complete engine maintenance and repair procedures.

Valve Adjustment: Check clearance every 6,000 miles
Cam Chain Tension: Automatic adjustment with manual override
Cylinder Head: Removal and installation procedures
Piston & Rings: Inspection and replacement guidelines
Crankshaft: Inspection and bearing replacement
Clutch: Adjustment and replacement procedures

CAUTION! Engine must be cool before disassembly. Use proper torque specifications.

Fuel System

Carburetor service and fuel system maintenance.

Component	Specification
Carburetor Type	Mikuni BST31SS x 4
Main Jet	#115
Pilot Jet	#40
Float Level	21.5 ± 1.0 mm
Idle Speed	1200 ± 100 rpm
Fuel Pump	Electric (if equipped)

Tip: Synchronize carburetors every 6,000 miles for smooth operation.

Electrical System

Complete electrical system diagnosis and repair.

Battery: 12V 10Ah maintenance-free
Alternator: Three-phase AC generator
Starter: Electric with reduction gear
Spark Plugs: NGK CR8E or equivalent
Fuses: Main 30A, Headlight 15A, Signal 10A
Bulbs: Headlight 60/55W, Brake 21W, Turn 21W

Chassis & Suspension

Frame, suspension, and steering maintenance.

Front Fork: Oil change procedure and seal replacement
Rear Shock: Preload adjustment and service
Steering Head: Bearing adjustment and replacement
Swingarm: Bearing inspection and lubrication
Wheels: Truing and bearing replacement

WARNING! Always use proper stands when working on chassis components.

Brake System

Hydraulic brake system service and maintenance.

Component	Specification
Front Brake	Dual disc, 2-piston calipers
Rear Brake	Single disc, 1-piston caliper
Master Cylinder	Front: 5/8", Rear: 1/2"
Brake Fluid	DOT 4
Pad Thickness	Replace if less than 1.0mm

Troubleshooting

Common problems and solutions for the GSXR 750.

Symptom	Possible Cause	Corrective Action
Hard starting	Weak battery, dirty carbs	Charge battery, clean carburetors
Poor idle	Sync needed, vacuum leak	Synchronize carbs, check hoses
Overheating	Low coolant, stuck thermostat	Check coolant level, replace thermostat
Electrical issues	Bad connections, failed component	Check grounds, test components
Brake problems	Air in lines, worn pads	Bleed brakes, replace pads

Wiring Diagrams

Complete electrical schematics for all systems.

Main harness routing and connections
Ignition system wiring
Charging system circuit
Lighting and signal circuits
Starter circuit diagram

Note: Refer to color codes for proper wire identification.

Torque Specifications

Critical fastener torque values for reassembly.

Component	Torque Value
Cylinder head bolts	40-45 ft-lbs
Spark plugs	13-17 ft-lbs
Oil drain plug	20-25 ft-lbs
Axle nuts	65-80 ft-lbs
Sprocket nuts	65-80 ft-lbs
Caliper bolts	20-25 ft-lbs
Fork clamp bolts	14-20 ft-lbs

CAUTION! Always use a calibrated torque wrench for critical fasteners.