1986 vt1100c service manual

The 1986 VT1100C is a 1098cc V-twin motorcycle featuring a liquid-cooled engine, 5-speed transmission, shaft drive, hydraulic disc brakes front and rear, and electronic ignition. This service manual covers maintenance, repair procedures, specifications, and troubleshooting for the complete motorcycle system. Below are key sections for technical data, maintenance schedules, engine service, chassis, electrical systems, and troubleshooting.

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

General Information

Key components: 1098cc 52° V-twin engine, 5-speed constant mesh transmission, shaft final drive, hydraulic disc brakes, electronic CDI ignition.

Component	Description
Engine Type	4-stroke, 52° V-twin, SOHC
Displacement	1098cc
Cooling System	Liquid-cooled with radiator
Transmission	5-speed constant mesh
Final Drive	Shaft drive
Ignition System	Electronic CDI
Brake System	Hydraulic disc front and rear
Fuel System	Dual CV carburetors
Frame Type	Double cradle steel
Suspension	Telescopic fork front, dual shocks rear

Maintenance Schedule

Regular maintenance intervals for optimal performance and safety.

Oil and filter change: Every 4,000 miles or 6 months
Valve clearance check: Every 8,000 miles
Spark plug replacement: Every 8,000 miles
Air filter cleaning: Every 4,000 miles
Brake fluid change: Every 2 years
Coolant replacement: Every 2 years or 16,000 miles
Drive shaft lubrication: Every 8,000 miles

WARNING! Always use genuine parts and recommended fluids. Disconnect battery before electrical work.

Engine Service

Complete engine maintenance and repair procedures.

Cylinder head removal: Remove exhaust, intake, and cam cover before head bolts
Valve adjustment: Set intake 0.004 in, exhaust 0.005 in cold
Piston and rings: Check ring end gap and piston clearance
Cam chain tension: Adjust with automatic tensioner
Oil pump: Check for proper pressure and flow
Cooling system: Flush radiator and check thermostat operation

CAUTION! Engine must be cool before disassembly. Use torque wrench for all critical fasteners.

Chassis & Suspension

Frame Inspection: Check for cracks or damage at stress points
Front Fork: Check oil level and seal condition
Rear Shocks: Inspect for oil leaks and spring condition
Steering Head: Adjust bearing play periodically
Wheels: Check for trueness and spoke tension
Tires: Maintain proper pressure (front 28 psi, rear 32 psi)
Swingarm: Lubricate pivot points every 8,000 miles

Electrical System

Complete electrical system diagnosis and repair.

Battery: 12V 14Ah, maintain specific gravity 1.260-1.280. Charging System: Three-phase alternator, output 350W at 5000 rpm. Ignition: CDI electronic ignition, timing fixed. Lights: Headlight 60/55W, brake/tail 21/5W, turn signals 21W.

Testing procedures: Battery voltage check, charging output test, spark intensity, circuit continuity.

Fuel System

Dual constant velocity carburetors, 34mm bore.

Carburetor synchronization: Use vacuum gauges for balance
Float level adjustment: 15.5mm from bowl mating surface
Pilot screw setting: 2-1/4 turns out from lightly seated
Fuel filter: Replace every 8,000 miles
Fuel pump: Check pressure and flow rate

Tip: Always clean fuel tank before carburetor service to prevent contamination.

Transmission & Drive

5-speed transmission with shaft final drive.

Clutch adjustment: Proper free play at lever (10-15mm)
Transmission oil: Change every 8,000 miles
Shift mechanism: Check for proper engagement and detent operation
Drive shaft: Lubricate splines every 8,000 miles
Final drive: Check oil level and condition
U-joint: Inspect for wear and proper lubrication

WARNING! Do not operate with worn drive components. Check for unusual noises or vibration.

Brake System

Hydraulic disc brakes front and rear.

Front: Dual piston caliper, 276mm disc. Rear: Single piston caliper, 276mm disc. Master cylinder rebuild, caliper service, pad replacement, brake line inspection.

Specifications

Engine: 1098cc, 52° V-twin, SOHC, 4 valves per cylinder
Bore x Stroke: 87.5mm x 91.4mm
Compression Ratio: 9.0:1
Fuel Capacity: 4.2 gallons
Oil Capacity: 3.7 quarts with filter change
Transmission Oil: 1.6 quarts
Final Drive Oil: 0.26 quarts
Wheelbase: 64.4 inches
Seat Height: 29.5 inches
Dry Weight: 584 pounds

Troubleshooting

Symptom	Possible Cause	Corrective Action
Hard starting	Weak battery, fuel delivery	Check battery voltage, clean carburetors, verify spark
Poor idle	Vacuum leak, sync issue	Check intake boots, synchronize carburetors
Overheating	Coolant level, thermostat	Check coolant, test thermostat, flush system
Electrical failure	Battery, stator, regulator	Test charging system components
Transmission noise	Low oil, worn gears	Check oil level, inspect gears
Brake drag	Stuck caliper, contaminated fluid	Rebuild caliper, flush brake fluid

Technical Support: Contact authorized dealer for complex repairs

Parts: Use genuine OEM parts for optimal performance and reliability