Target Audience:
Owners and independent repair shops seeking professional-grade documentation for servicing and repairing Yamaha Moto 4 250 and 350 models.
Value Proposition:
Provides the same level of detail and accuracy as OEM service manuals at a fraction of the cost, enabling cost savings on repair and maintenance. Eliminates the need for multiple, fragmented repair guides.
Unique Selling Points:
Instant download access, factory-type quality, comprehensive coverage, detailed diagrams, step-by-step instructions, PC/Mac compatibility, cost-effective repair solution.
Years Covered:
1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995
Estimated Page Count:
Extensive (typical for a comprehensive factory service manual)
Type:
Factory Type Service Repair Workshop Manual
Format:
PDF (Portable Document Format)
Engine:
Engine overhaul, diagnostics, tuning, cooling system, lubrication system, starting system, ignition system, fuel system (carburetion, fuel delivery), exhaust system.
Transmission:
Gearbox service, clutch operation and adjustment, drive shaft, differential, torque converter (if applicable).
Chassis And Suspension:
Front suspension (forks, steering), rear suspension (shock absorbers, swingarm), wheel bearings, steering system, frame inspection and repair.
Brakes:
Hydraulic brake system (master cylinder, calipers, lines), brake pad replacement, brake fluid flush and bleeding, parking brake adjustment.
Electrical System:
Wiring diagrams, battery service, lighting system, charging system (stator, regulator/rectifier), starting system (starter motor, solenoid), ignition system components (CDI, coils), instrumentation, fuses, relays.
Body And Trim:
Fender removal/installation, seat removal/installation, handlebar components, plastic panel repairs, decals, rack systems.
Maintenance:
Scheduled maintenance tasks, oil and filter changes, air filter cleaning/replacement, spark plug replacement, lubrication points, pre-ride inspections.
Troubleshooting:
Diagnostic charts for common problems, symptom-based troubleshooting guides for engine performance, electrical issues, and starting problems.
Repair And Rebuild:
Step-by-step instructions for component disassembly, inspection, repair, and reassembly, including engine rebuilds, transmission overhaul, carburetor rebuilding.
Adjustment:
Carburetor jetting and idle speed adjustment, clutch cable adjustment, brake lever free play adjustment, chain tension adjustment.
Depth:
Comprehensive, covering everything from basic maintenance to complete engine and transmission overhauls, electrical system diagnostics, and component rebuilding. Designed for professional mechanic-level understanding and execution.
Compatibility:
PC & MAC Compatible
Quality:
High-resolution, professionally scanned PDF with clear, legible text and sharp, detailed diagrams and exploded views.
Binding:
N/A (Digital Download)
Paper Type:
N/A (Digital PDF)
Text Search:
Searchable text within the PDF for quick information retrieval.
Print On Demand:
Print what you need, when you need it. Allows for targeted printing of specific sections or entire chapters.
Engine Type:
Air-cooled, 4-stroke, SOHC, 2-valve, single-cylinder
Displacement 250:
230cc (approximate, varies slightly by specific model year)
Bore X Stroke 250:
68.0 mm x 64.0 mm (typical)
Compression Ratio 250:
9.0:1 (typical)
Engine Type:
Air-cooled, 4-stroke, SOHC, 2-valve, single-cylinder
Displacement 350:
348cc (approximate, varies slightly by specific model year)
Bore X Stroke 350:
82.0 mm x 64.0 mm (typical)
Compression Ratio 350:
8.5:1 (typical)
Horsepower 250:
Approx. 15-20 HP (varies by year and tuning)
Horsepower 350:
Approx. 20-25 HP (varies by year and tuning)
Carburetor:
Mikuni VM Series (single carburetor, size varies by model year and displacement)
Fuel Type:
Unleaded gasoline
Oil Type:
SAE 10W-40 API SE, SF or SG (or equivalent JASO MA)
Oil Capacity With Filter:
Approx. 1.8-2.0 Liters (check specific model year for exact capacity)
Type:
Manual, constant mesh, 5-speed (standard on most models)
Clutch:
Wet, multi-plate, manual operation
Final Drive:
Shaft drive (enclosed, low maintenance)
Gear Ratios:
Detailed gear ratios for each speed are provided in the manual.
Wheelbase:
Varies by year and model, typically around 48-50 inches (1220-1270 mm).
Overall Length:
Varies by year and model, typically around 70-74 inches (1780-1880 mm).
Dry Weight:
Approx. 400-450 lbs (180-205 kg) depending on model and configuration.
Gvwr:
Not typically specified for ATVs, but payload capacity is implied.
Racks:
Front and rear cargo racks with substantial weight carrying capacity (specific ratings vary).
Atv Safety Standards:
Designed to meet relevant ATV safety standards of the era.
Braking System:
Hydraulic front disc brakes, rear drum brake (or dual front disc on some later models).
Handlebar Design:
Ergonomic handlebar with grip heaters (optional on some models) and protective pads.
Lighting:
Dual headlights, taillight, and brake light for visibility.
Engine Oil Change:
Every 1000-1500 miles or 6 months, whichever comes first.
Air Filter Cleaning:
Every 500-1000 miles or every 3 months (more frequently in dusty conditions).
Spark Plug Replacement:
Every 3000-5000 miles or annually.
Gear Oil Change:
Every 2000-3000 miles or annually.
Brake Fluid:
DOT 3 or DOT 4 hydraulic brake fluid.
Final Drive Gear Oil:
Hypoid gear oil, SAE 80W-90.
Carburetor Cleaning:
Carburetors can be prone to clogging from stale fuel or debris, requiring regular cleaning and adjustment, especially if the ATV sits for extended periods.
Electrical Connections:
Corrosion can occur at electrical connectors, leading to intermittent electrical issues. Regular inspection and cleaning are recommended.
Cooling System Airlocks:
Air-cooled engines can overheat if not properly maintained. Ensure cooling fins are clean.
Suspension Seals:
Fork seals and rear shock bushings can wear over time, leading to leaks or reduced damping performance.
Yamaha Atv Legacy:
Yamaha has a strong history in powersports, including pioneering the ATV market with models like the 'Tri-Z' and 'Blaster', and the durable Moto 4 series.
Moto 4 Lineage:
The Moto 4 series was Yamaha's workhorse utility ATV, known for its ruggedness, reliability, and shaft drive. Introduced in the mid-1980s, it offered both 2WD and 4WD variants, with the 250 and 350cc engines being the most common. The series saw continuous refinements through the late 80s and early 90s.
Manufacturing Location:
Primarily manufactured in Japan.
