🏷️ Basic Information

Make:

Yamaha

Model:

TRI-Z / YTZ250

Year:

1984

Model Code:

YTZ250N

Engine Code:

YTZ250

👋 Introduction

Market Position:

The Yamaha TRI-Z 250 was a high-performance, sport-oriented ATV in the mid-1980s, competing with other leading manufacturers' performance models. It was targeted at enthusiasts seeking aggressive trail riding and racing capabilities.

Competitive Analysis:

Key competitors in the sport ATV segment during this era included models from Honda (like the TRX series), Kawasaki, and Suzuki. The TRI-Z distinguished itself with its powerful two-stroke engine and advanced suspension for its time.

Key Features:

Powerful 246cc two-stroke engine, liquid-cooling, aggressive styling, robust suspension for off-road performance, popular among motocross and trail riding communities.

📋 Manual Details

Coverage Areas:

Engine, Chassis, Electrical Systems, Regular Maintenance and Adjustments, Troubleshooting

Page Count:

Not Specified (Preview PDF)

Manual Type:

Service Repair Manual

Language:

English

Format:

PDF

📖 Manual Coverage

Systems Covered:

Engine (Disassembly, Assembly, Tuning, Carburetion), Fuel System, Ignition System, Lubrication System, Cooling System, Exhaust System, Transmission, Clutch, Drivetrain, Suspension (Front and Rear), Steering, Brakes (Front and Rear), Wheels and Tires, Frame, Bodywork, Electrical System (Wiring Diagrams, Components, Troubleshooting), Lighting, Controls

Procedures Included:

Routine maintenance, scheduled maintenance, inspections, adjustments (carburetor, clutch, brakes, suspension), engine rebuilds, transmission service, clutch replacement, suspension fork service, brake bleeding, electrical system troubleshooting, wiring harness repair, component testing and replacement

Technical Depth:

Comprehensive, covering from basic owner maintenance to in-depth technician-level repairs and diagnostics. Includes detailed diagrams, specifications, and step-by-step instructions.

📊 Manual Specifications

File Format:

PDF

Print Quality:

High-resolution, clear text and legible diagrams (typical for service manuals)

Binding Type:

Digital (PDF Download)

Paper Type:

Not Applicable (Digital)

Compatibility:

All versions of Windows & Mac

Requirements:

Adobe PDF Reader

⚙️ Engine Specifications

Primary Engine:

246cc, 2-stroke, reed valve, liquid-cooled, single-cylinder

Bore X Stroke:

66.0 mm x 72.0 mm

Compression Ratio:

6.8:1

Carburetor:

Mikuni VM34SS (single)

Fuel Type:

Unleaded gasoline (typically 87 octane or higher recommended, check manual for specifics)

Ignition System:

CDI (Capacitor Discharge Ignition)

Cooling Method:

Liquid-cooled

Lubrication System:

Premix or Autolube (2-stroke oil injection system - specific to model variant, check manual)

🔧 Transmission

Transmission Type:

Constant-mesh 5-speed with manual clutch

Clutch Type:

Wet, multi-plate

Drive Type:

Shaft drive (to rear axle)

Final Drive:

O-ring sealed chain

📐 Dimensions

Overall Length:

Approx. 1885 mm (74.2 in)

Overall Width:

Approx. 810 mm (31.9 in)

Overall Height:

Approx. 1070 mm (42.1 in)

Dry Weight:

Approx. 170 kg (375 lbs)

Fuel Capacity:

Approx. 12.0 L (3.2 US gal)

Oil Capacity:

Refer to manual for 2-stroke oil injection tank capacity (if equipped) and transmission oil capacity.

🛡️ Safety Features

Ratings:

Not applicable in the same way as passenger vehicles. ATV safety is governed by manufacturer guidelines and user responsibility. Always wear appropriate safety gear.

Active Features:

Disc brakes (front and rear), responsive handling, aggressive tire tread for traction.

Passive Features:

Handlebar grips, footpegs with heel guards for rider stability.

💡 Technology Features

Infotainment:

N/A (Mechanical/Sport focus)

Driver Assistance:

N/A (Mechanical/Sport focus)

Connectivity:

N/A (Mechanical/Sport focus)

Performance Enhancements:

Liquid cooling for consistent engine performance, powerful 2-stroke engine design for spirited riding.

🔧 Maintenance

Service Intervals:

Refer to manual for specific intervals for: engine oil changes (transmission), spark plug inspection/replacement, air filter cleaning/replacement, chain adjustment/lubrication, brake pad inspection, suspension service. General guideline: post-ride checks, frequent lubrication, and periodic comprehensive inspections are recommended.

Transmission Oil Type:

Yamalube 4 (or equivalent SAE 10W-30 API SE or SF classified 4-stroke engine oil), Capacity: Refer to manual for exact amount (typically around 0.6-0.8 L).

Coolant Type:

Ethylene glycol based antifreeze coolant (50% mixture with distilled water). Capacity: Refer to manual.

2 Stroke Oil Type:

High-quality 2-stroke engine oil specifically designed for liquid-cooled, high-performance engines (e.g., Yamalube 2-stroke oil). Check manual for specific viscosity and API classification if using premix.

Known Issues:

Common issues for this era of high-performance 2-stroke ATVs can include carburetor tuning difficulties, reed valve wear, clutch wear, suspension seal leaks, and electrical component aging. Proper maintenance and use of correct fluids are critical.

Tune Up Procedures:

Carburetor cleaning and adjustment, spark plug gap and condition check, air filter cleaning/replacement, exhaust system inspection, chain tension check and lubrication, fuel filter check.

📚 Vehicle History

Brand Heritage:

Yamaha has a long and successful history in motorsports and powersports, including a strong presence in the early development and popularization of ATVs.

Model Evolution:

The TRI-Z (YTZ250) was a significant model for Yamaha in the sport ATV segment, evolving from earlier ATV designs to offer more performance and sport-oriented features. It set a benchmark for its class.

Production Years:

1984-1985 (for YTZ250/N model)

Manufacturing Location:

Japan (typically)

🏆 Awards & Recognition

Recognitions:

While specific awards for this model year might be hard to pinpoint, the Yamaha TRI-Z line was highly regarded in its time for its performance and racing pedigree within the sport ATV community.