1986 Yamaha Moto 4 350 Manual

The 1986 Yamaha Moto 4 350 is a rugged all-terrain vehicle featuring a 348cc four-stroke engine, shaft drive system, full floorboards, reverse gear, electric start, dual-range transmission, front and rear racks, and full suspension. This manual covers operation, maintenance, troubleshooting, and specifications for proper care and optimal performance of your ATV.

1. Features at a Glance 2. Pre-Ride Inspection 3. Operation Controls 4. Specifications 5. Maintenance Schedule 6. Engine Service 7. Transmission & Drive 8. Brake System 9. Storage & Winterization 10. Safety Information 11. Troubleshooting

Features at a Glance

Key components: 348cc air-cooled 4-stroke engine, shaft drive, full floorboards, reverse gear, electric start, dual-range transmission.

Feature	Description
Engine	348cc 4-stroke, air-cooled single cylinder
Drive System	Shaft drive with reverse gear
Transmission	5-speed with dual-range (high/low)
Starting System	Electric start with backup kick starter
Suspension	Front telescopic forks, rear swingarm
Brakes	Front and rear drum brakes
Fuel Capacity	3.7 gallons (14 liters)
Load Capacity	Front and rear cargo racks
Weight	423 lbs (192 kg)
Dimensions	76.4" L x 42.5" W x 43.3" H

Pre-Ride Inspection

Always perform safety check before operating.

Check fuel level: Ensure adequate fuel for planned ride.
Inspect tires: Check pressure and condition for wear/damage.
Test brakes: Verify front and rear brake operation.
Check controls: Ensure throttle, clutch, and shift lever move freely.
Verify lights: Test headlight, taillight, and brake light function.

WARNING! Never operate ATV without proper safety inspection. Always wear helmet and protective gear.

Operation Controls

Familiarize yourself with all controls before riding.

Handlebar Controls: Throttle, front brake lever, clutch lever, ignition switch, light switch, choke.

Foot Controls: Shift lever, rear brake pedal, footpegs.

Instrument Panel: Speedometer, odometer, neutral indicator, high beam indicator.

Starting Procedure: Turn fuel valve ON, set choke for cold starts, ensure in neutral, turn key to start position.

Specifications

Engine Type: 4-stroke, air-cooled, SOHC
Displacement: 348cc
Bore x Stroke: 83.0 x 64.5mm
Compression Ratio: 8.3:1
Carburetor: Mikuni VM32SS
Ignition: CDI
Transmission: 5-speed with reverse
Final Drive: Shaft
Fuel System: Gravity feed
Oil Capacity: 2.1 quarts (2.0 liters)
Tire Size: Front 23x8-11, Rear 25x12-11

Maintenance Schedule

Regular maintenance ensures long service life and reliability.

Service Item	Every 100 mi	Every 500 mi	Every 1000 mi
Engine Oil	Check	Change	Change
Oil Filter	-	-	Replace
Air Filter	Clean	Clean	Replace
Spark Plug	Check	Clean	Replace
Brake Pads	Inspect	Inspect	Replace if worn
Drive Shaft	Lubricate	Lubricate	Lubricate
Tire Pressure	Check	Check	Check

Engine Service

Proper engine maintenance is critical for performance.

Oil Change: Warm engine, drain oil, replace filter, refill with SAE 10W-40.
Air Filter: Remove foam element, wash in solvent, oil lightly, reinstall.
Spark Plug: Clean and gap to 0.6-0.7mm, replace if electrodes worn.
Valve Clearance: Check every 1000 miles - intake 0.08-0.12mm, exhaust 0.10-0.14mm.
Carburetor: Clean jets and passages if engine runs rough or stalls.

CAUTION! Engine must be cool before servicing. Use proper tools and torque specifications.

Transmission & Drive

Shaft drive system requires regular maintenance.

Gear Oil: Check level regularly, change every 2000 miles.
Shift Mechanism: Lubricate linkage points every 500 miles.
Drive Shaft: Grease splines and U-joints every 1000 miles.
Reverse Operation: Come to complete stop before engaging reverse gear.

Tip: Use only recommended gear oil for transmission and final drive.

Brake System

Drum brakes front and rear require periodic adjustment.

Brake Adjustment: Turn adjuster nuts on brake rods to eliminate free play.
Brake Shoes: Replace when lining thickness reaches 1.0mm minimum.
Cables: Lubricate brake cables every 500 miles.
Fluid: Check master cylinder level if equipped with hydraulic brakes.

WARNING! Test brakes after adjustment. Never ride with improperly functioning brakes.

Storage & Winterization

Proper storage prevents damage during extended non-use.

Fuel System: Add fuel stabilizer and run engine for 5 minutes.
Battery: Remove and store in cool, dry place with periodic charging.
Tires: Inflate to maximum pressure and elevate off ground.
Engine: Change oil and filter before storage.
Exterior: Clean thoroughly and apply protective coating to metal surfaces.

CAUTION! Store in dry location away from direct sunlight and moisture.

Safety Information

Always follow safety guidelines when operating ATV.

Wear approved helmet, eye protection, gloves, and sturdy footwear
Never carry passengers - designed for operator only
Avoid paved surfaces - not designed for road use
Never operate under influence of alcohol or drugs
Ride within your skill level and at safe speeds
Be aware of terrain and environmental conditions
Keep hands and feet away from moving parts

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	Fuel, spark, compression	Check fuel valve, spark plug, choke setting
Poor performance	Dirty air filter, carburetor	Clean air filter, check carburetor jets
Hard shifting	Clutch adjustment, oil level	Adjust clutch cable, check transmission oil
Electrical issues	Battery, connections	Check battery charge, clean connections
Overheating	Low oil, dirty fins	Check oil level, clean cooling fins
Brakes weak	Worn shoes, adjustment	Adjust brakes, replace shoes if worn

Service: Contact authorized Yamaha dealer for major repairs.

Parts: Use genuine Yamaha parts for optimal performance and reliability.