Yamaha Tri-Z 250 Repair and Service Manual 1985-1985.5 YTZ250

Precio habitual: $16.99
Precio de venta: $16.99
Precio habitual
Precio unitario: por

29 people are viewing this right now

Tipo: Atv

Proveedor:

SKU: 91847

Etiquetas: 1985 ATV Powersports Tri Z Models Tri-Z 250 Yamaha YTZ250

Variantes de producto

Descripción

The Tri-Z 250, model code YTZ250, specifically the YTZ250N variant, was a formidable sport ATV produced in 1985 and the subsequent 1985.5 model year. Designed for high-performance recreational riding, particularly in challenging off-road environments like sand dunes, the Tri-Z 250 distinguished itself with its powerful 246cc liquid-cooled two-stroke engine, advanced long-travel suspension, and effective disc brake systems. Its engineering emphasized agility and power, making it a competitive and exciting choice in the sport ATV market of its era, building on an established reputation for performance and innovation in powersports. This comprehensive 137-page English-language manual serves as an indispensable resource for the maintenance, repair, and understanding of the Tri-Z 250. It covers all critical systems, including detailed engine overhaul procedures, transmission maintenance, chassis and suspension adjustments, brake system servicing, and electrical system troubleshooting. The manual provides routine maintenance schedules, step-by-step repair instructions, diagnostic guidance, and factory specifications essential for both owners and professional technicians. Its clear illustrations and detailed explanations ensure that owners and mechanics can effectively maintain and restore the Tri-Z 250 to optimal working condition.

🏷️ Basic Information

Identification

Make:

Yamaha

Model:

Tri-Z 250

Model Code:

YTZ250

Model Variant:

YTZ250N

Year:

1985 / 1985.5

👋 Introduction

Market Position

Market Position:

The Yamaha Tri-Z 250 was a high-performance, specialized three-wheeler ATV designed for sport riding, particularly in sand dune environments. It occupied a niche but significant segment of the ATV market in the mid-1980s.

Competitive Analysis

Competitive Analysis:

Competed against other performance ATVs of the era, including models from Honda (like the ATC250R) and Suzuki. The Tri-Z was known for its powerful engine and aggressive styling.

Key Features

Key Features Of Vehicle:

Powerful 246cc liquid-cooled 2-stroke engine, long-travel suspension, disc brakes, and a reputation for being a capable and exciting sport ATV.

Key Features Of Manual

Key Features Of Manual:

Detailed illustrations, clear step-by-step instructions, troubleshooting assistance, factory specifications, used by professional technicians, DIY friendly.

📋 Manual Details

Coverage Areas

Vehicle Covered:

Yamaha Tri-Z 250 YTZ250 (1985-1985.5)

Page Count

Page Count:

Manual Type

Manual Type:

Repair and Service Manual / Workshop Manual / Factory Manual

Language

Language:

English

Format

Format:

PDF Download

📖 Manual Coverage

Systems Covered

Engine:

Complete engine overhaul, diagnosis, performance tuning, carburetor adjustment, fuel system, lubrication, ignition system, cooling system (radiator, coolant), exhaust system (muffler).

Transmission:

Gearbox, primary reduction gear, clutch, transmission fluid, gear shifting mechanisms.

Chassis And Suspension:

Frame, front forks, rear suspension (struts, swingarm, linkage), steering system, wheels, tires.

Brakes:

Front and rear brake systems, brake fluid, brake pads, rotors, hydraulic system.

Electrical System

Electrical System:

Ignition system (magneto, coil, plug), starting system (kickstart, starter), lighting, switches, battery, rectifier, wiring diagrams, troubleshooting electrical problems (no spark).

Bodywork And Plastics

Bodywork And Plastics:

Panels, fenders, seat, handlebars, plastics.

Procedures Included

Maintenance:

Routine maintenance, preventative maintenance schedules, fluid changes, filter replacements, lubrication points.

Repair And Rebuild:

Detailed step-by-step instructions for repairing, rebuilding, and restoring all major components.

Troubleshooting:

Comprehensive troubleshooting guides for diagnosing and resolving common and uncommon problems.

Diagnostics:

Diagnostic procedures for identifying the root cause of issues.

Technical Depth

Technical Depth:

Complete coverage from basic adjustments to full engine rebuilds and complex electrical system diagnosis.

📊 Manual Specifications

File Format

File Format:

File Compatibility:

Windows, Linux, Mac OS

File Enhancement:

Requires WinZip or WinRAR for unzipping if compressed.

Print Quality

Print Quality:

Printable on any computer

Binding Type

Binding Type:

Digital Download (No physical copy)

Paper Type

Paper Type:

N/A (Digital)

⚙️ Engine Specifications

Primary Engine

Engine Type:

2-stroke, liquid-cooled

Displacement:

239cc (actual displacement often cited as 243cc or 246cc depending on source and tuning)

Bore X Stroke:

68.0 mm x 64.0 mm

Compression Ratio:

6.7:1 (typical for this era, can vary slightly)

Carburetor:

Single Mikuni VM34SS (often cited as 34mm)

Performance

Horsepower:

Approximately 24-26 HP (at the crankshaft, estimations vary)

Torque:

Not explicitly stated in common documentation, but significant for its class.

Fuel System

Fuel Type:

Unleaded gasoline with 2-stroke oil mixture (pre-mix)

Oil Viscosity Recommendation:

2-stroke specific oil (Yamaha recommends Yamalube 2, SAE 10W-30 or 20W-40 for general use, consult manual for specifics).

Engine Components

Cylinder:

Single cylinder

Crankshaft:

Forged crankshaft

Connecting Rod:

Conrod

Valves:

Reed valve induction

Camshaft:

N/A (2-stroke engines typically do not have camshafts in the traditional sense; rely on reed valves).

Ignition

Ignition System:

CDI (Capacitor Discharge Ignition)

Magneto:

Internal magneto ignition

🔧 Transmission

Standard

Transmission Type:

6-speed constant mesh

Clutch Type:

Wet multi-plate

Drive Train:

Chain drive

Gear Ratios:

Specific gear ratios are detailed within the manual.

Features

Gearshift:

Heel-toe shift lever

📐 Dimensions

Weights

Dry Weight:

Approximately 150 kg (330 lbs)

Fuel Tank Capacity:

Approximately 10 liters (2.6 US gallons)

Oil Tank Capacity:

Approximately 1.5 liters (0.4 US gallons)

Cooling System Capacity:

Approximately 1.3 liters (1.4 US quarts)

🔧 Maintenance

Service Intervals

Engine Oil Change Interval:

Refer to manual for specific transmission oil change intervals (typically every 1000-2000 km or annually). Pre-mix ratio is critical.

Air Filter Cleaning:

Regular inspection and cleaning, especially in dusty conditions. Manual specifies frequency.

Spark Plug Maintenance:

Inspect and gap spark plug at regular intervals (e.g., every 1000 km or annually). Manual specifies plug type and gap.

Fluid Specifications

Engine Oil Type:

2-stroke specific, pre-mix. Refer to manual for exact Yamaha specifications or equivalent high-quality 2T oil.

Transmission Oil Type:

Yamaha recommends SAE 10W-30 API SE or SF. Consult manual for precise specifications and capacity.

Coolant Type:

Permanent type antifreeze (ethylene glycol based) mixed with distilled water. Refer to manual for ratio and type.

Brake Fluid Type:

DOT 3 or DOT 4 brake fluid.

Known Issues

Known Issues:

Common issues for this era of 2-stroke ATVs can include carburetor jetting sensitivity, reed valve wear, clutch engagement issues, cooling system leaks (hose degradation), and electrical component failures (e.g., CDI unit). Overheating can occur if cooling system is not maintained.

Technical Specifications

Tire Pressure Front:

Specific PSI will be detailed in the manual, typically around 4-6 PSI for dune riding.

Tire Pressure Rear:

Specific PSI will be detailed in the manual, typically around 2-4 PSI for dune riding.

Spark Plug Gap:

Refer to manual for exact specification, typically around 0.6-0.7 mm (0.024-0.028 in).

Valve Clearance:

N/A (2-stroke engine).

Carburetor Pilot Jet Size:

Refer to manual for specific jet sizes and tuning.

Carburetor Main Jet Size:

Refer to manual for specific jet sizes and tuning.

Carburetor Mixture Screw Setting:

Refer to manual for proper idle mixture adjustment.

Torque Specs:

Comprehensive torque specifications for all critical fasteners (engine, chassis, suspension, etc.) are provided in the manual.

📚 Vehicle History

Brand Heritage

Brand Heritage:

Yamaha has a long history in powersports, known for its innovation and performance in motorcycles, ATVs, and marine products. Their expertise in 2-stroke engine technology is well-established.

Model Evolution

Model Evolution:

The Tri-Z (YTZ250) was a successor and evolution from earlier Yamaha sport ATVs, incorporating liquid cooling and a 6-speed transmission for improved performance and reliability. It represented Yamaha's commitment to the sport ATV segment.

Production

Production Period:

The YTZ250 model was primarily produced in 1985, with minor updates sometimes referred to as '1985.5'.