Market Position:
A crucial resource for owners and mechanics maintaining the 1986 Yamaha Moto-4 60 youth ATV, a popular model for its entry-level performance and durability. Positioned as an essential tool for DIY enthusiasts and professional service shops alike.
Competitive Analysis:
In its era, the Moto-4 60 competed with other entry-level youth ATVs from brands like Honda (e.g., ATC70, TRX70) and Suzuki. This manual provides factory-level detail, setting it apart from generalized repair guides.
Key Features:
Factory-authorized repair procedures, detailed illustrations and diagrams, comprehensive troubleshooting guides, essential technical specifications (torque, clearances), and a user-friendly digital format with search and navigation capabilities.
Coverage Areas:
Complete teardown and rebuild, maintenance, troubleshooting, part diagrams, torque specifications, electrical system, engine, transmission, brakes, suspension, chassis, bodywork, plastics, fuel system, exhaust system, charging system, ignition system, starting system, lubrication system, cooling system (if applicable), wheels, tires, steering, lighting, accessories.
Manual Type:
Factory Service Manual / Repair Manual
Systems Covered:
Engine (top end, bottom end, carburetor, ignition, starting, lubrication), Transmission (gearbox, clutch), Drive Train (shaft drive, differential), Fuel System (tank, fuel pump, lines), Exhaust System, Electrical System (charging, lighting, ignition, starter), Braking System (front and rear), Suspension (front forks, rear swingarm), Steering System, Chassis and Frame, Bodywork and Plastics, Wheels and Tires.
Procedures Included:
Routine maintenance, scheduled maintenance, diagnostics, troubleshooting (e.g., no spark, starting issues, performance problems), complete engine rebuild, transmission overhaul, carburetor adjustment and rebuilding, brake servicing, suspension component replacement, electrical system testing and repair, chassis component inspection, plastic panel removal and installation, fluid changes (oil, coolant, brake fluid), spark plug replacement, battery maintenance.
Technical Depth:
Comprehensive, covering from basic user maintenance to full mechanical and electrical system overhauls. Includes detailed step-by-step instructions, torque specifications, valve clearances, wiring diagrams, exploded views, and diagnostic flowcharts.
Engine Type:
Air-cooled, 2-stroke, single-cylinder
Displacement:
50-60 cc (Specific CC may vary based on exact model variant, typically around 50-55cc)
Bore X Stroke:
Refer to manual for exact specifications (typical for this class: approx. 40mm x 39mm)
Compression Ratio:
Refer to manual for exact specifications (typical for 2-stroke: 6.0:1 to 7.5:1 range)
Lubrication System:
Pre-mix fuel/oil or Autolube injection (refer to manual for specific system)
Horsepower:
Refer to manual for exact specifications (typically 4-6 HP)
Torque:
Refer to manual for exact specifications
Carburetor Type:
Mikuni VM Series (Specific model number like VM14 or VM16 likely)
Fuel Delivery:
Gravity feed from fuel tank via fuel valve
Pilot Jet Size:
Refer to manual (e.g., #12.5, #15)
Main Jet Size:
Refer to manual (e.g., #70, #75)
Air Filter:
Foam or paper element, typically housed in a sealed airbox.
Transmission Type:
Automatic (CVT - Continuously Variable Transmission) or Torque Converter with Reduction Gears
Gear Ratios:
Refer to manual for specific low and high range ratios.
Clutch Type:
Centrifugal automatic clutch
Drive System:
Shaft drive to rear axle
Reverse:
Yes, typically via a separate reverse gear mechanism.
Length:
Refer to manual for exact specifications (approx. 1400-1500 mm)
Width:
Refer to manual for exact specifications (approx. 800-900 mm)
Height:
Refer to manual for exact specifications (approx. 900-1000 mm)
Dry Weight:
Refer to manual for exact specifications (typically 60-70 kg)
Payload Capacity:
Refer to manual for specific load limits.
Towing Capacity:
Not typically specified for youth ATVs.
Front Tire Size:
Refer to manual (e.g., AT16x6.5-7)
Rear Tire Size:
Refer to manual (e.g., AT18x9.5-8)
Wheel Bolt Pattern:
Refer to manual (likely 4-bolt, common pattern for ATVs of this era)
Safety Ratings:
N/A (ATVs typically not subject to the same standardized safety ratings as passenger vehicles).
Active Safety Features:
Mechanical brakes (front and rear drums/discs), throttle limiter (potential feature on youth models), kill switch lanyard.
Passive Safety Features:
Durable frame construction, plastic body panels, handlebar padding, footwells.
Routine Maintenance:
Daily checks: Tire pressure, fuel level, brake operation. Weekly/Monthly checks: Oil level (if applicable), chain tension (if applicable), air filter cleaning, spark plug inspection. Seasonal checks: Carburetor cleaning, fuel system inspection, battery check.
Engine Oil Type:
Yamalube 2-stroke oil (or equivalent TC-W3 certified oil) for pre-mix or oil injection reservoir. Refer to manual for specific viscosity and mix ratio if applicable.
Transmission Oil Type:
Yamalube Gear Oil (or equivalent SAE 80W API GL-4) for gearbox and final drive. Refer to manual for specific viscosity and capacity.
Brake Fluid Type:
DOT 3 or DOT 4 hydraulic brake fluid (for hydraulic brakes, if equipped, otherwise mechanical).
Coolant Type:
Not applicable, as it is air-cooled.
Common Issues:
Carburetor clogging due to old fuel, ignition system problems (spark plug, coil, CDI), fuel line degradation, wear and tear on suspension components, starter motor issues, exhaust leaks, piston ring wear.
Preventative Maintenance:
Regular cleaning of carburetor, proper fuel storage, timely spark plug replacement, regular air filter cleaning/replacement, checking for air leaks in intake and exhaust systems, proper oil-fuel mixture if applicable.
Spark Plug Gap:
Refer to manual (e.g., 0.6-0.7 mm)
Valve Clearance:
Not applicable (2-stroke engine).
Carburetor Adjustment:
Idle speed adjustment, mixture screw adjustment (refer to manual for specific settings).
Chain Maintenance:
Lubrication and tension adjustment (if equipped with chain drive, typically rear drive is shaft).
Brand Heritage:
Yamaha has a long-standing reputation for producing reliable and innovative powersports vehicles, including a significant history in ATVs dating back to the early 1980s with models like the Tri-Z and Moto-4 series.
Model Evolution:
The Moto-4 60 (YF60) was part of Yamaha's initial foray into the youth ATV market, designed to introduce younger riders to the sport with a user-friendly and manageable machine. It paved the way for later Yamaha youth ATV models.
Production Years:
Mid-1980s (1985-1987 typically for the 60cc model, with variations in name/specifications).
Manufacturing Location:
Likely Japan or USA (Yamaha facilities).
