1987 Yamaha TT 225 Service Manual

The 1987 Yamaha TT 225 is a dual-sport motorcycle featuring a 223cc air-cooled four-stroke single-cylinder engine, 5-speed transmission, electric start with kick starter backup, front disc brake, rear drum brake, and dual-purpose tires. This service manual covers maintenance procedures, specifications, troubleshooting, and repair instructions for proper upkeep and operation of the motorcycle. Below are key sections for safety, features, maintenance procedures, specifications, and troubleshooting.

1. Features at a Glance 2. Safety Precautions 3. Maintenance Schedule 4. Specifications 5. Engine Service 6. Transmission & Clutch 7. Electrical System 8. Brake System 9. Suspension & Steering 10. Troubleshooting

Features at a Glance

Key components: 223cc SOHC engine, 5-speed constant mesh transmission, CDI ignition, electric start, front telescopic fork, rear swingarm suspension.

Feature	Description
Engine Type	Air-cooled 4-stroke SOHC single cylinder
Displacement	223cc
Bore x Stroke	70.0 x 58.0 mm
Compression Ratio	9.5:1
Starting System	Electric with kick starter backup
Transmission	5-speed constant mesh
Final Drive	Chain
Front Brake	Hydraulic disc
Rear Brake	Mechanical drum
Fuel Capacity	2.4 gallons (9.1 liters)

Safety Precautions

Always follow safety procedures when servicing motorcycle.

Work in well-ventilated area: Avoid inhaling exhaust fumes or chemical vapors.
Use proper tools: Ensure tools are in good condition and appropriate for the task.
Disconnect battery: Before electrical work, disconnect negative terminal.
Support motorcycle securely: Use center stand or proper lift for stability.

WARNING! Gasoline is highly flammable; keep away from sparks and open flames. Engine and exhaust become very hot during operation.

Maintenance Schedule

Regular maintenance ensures optimal performance and longevity.

Pre-ride inspection: Check tires, brakes, lights, chain tension, fluid levels.
Every 600 miles: Change engine oil and filter, check/adjust drive chain.
Every 3,000 miles: Clean air filter, check valve clearance, inspect brake pads.
Every 6,000 miles: Replace spark plug, check carburetor synchronization.
Seasonal: Check battery electrolyte level, lubricate cables and pivots.

CAUTION! Use only Yamaha recommended lubricants and replacement parts.

Specifications

Engine: 223cc 4-stroke SOHC, 9.5:1 compression
Fuel System: Mikuni VM26SS carburetor
Ignition System: CDI (Capacitor Discharge Ignition)
Lubrication System: Wet sump
Transmission: 5-speed constant mesh
Frame: Steel semi-double cradle
Front Suspension: Telescopic fork, 7.1 inches travel
Rear Suspension: Swingarm with dual shocks, 6.3 inches travel
Front Tire: 3.00-21
Rear Tire: 4.60-18
Dry Weight: 249 lbs (113 kg)

Engine Service

Engine maintenance procedures including oil changes, valve adjustment, and top-end service.

Oil Change: Warm engine, drain oil, replace filter, refill with 1.7 quarts SAE 10W-40.

Valve Clearance: Intake: 0.002-0.003 in (0.05-0.08 mm), Exhaust: 0.003-0.004 in (0.08-0.10 mm). Adjust when engine is cold.

Carburetor: Main jet #130, pilot jet #40, needle clip 3rd position, float level 0.98 in (25 mm).

Transmission & Clutch

Transmission oil capacity: 1.1 quarts SAE 10W-30. Clutch adjustment: Free play 10-15mm at lever end.

Check transmission oil level with motorcycle upright.
Adjust clutch cable at handlebar lever.
Inspect clutch plates for wear every 6,000 miles.
Check drive chain tension: 1.2-1.6 inches (30-40 mm) free play.

Tip: Lubricate drive chain every 300 miles with chain lubricant.

Electrical System

12V electrical system with battery, alternator, CDI ignition, and lighting.

Battery: 12V 8Ah, maintain electrolyte level between upper and lower marks.
Spark Plug: NGK DR8ES-L, gap 0.024-0.028 in (0.6-0.7 mm).
Charging System: AC magneto with rectifier/regulator.
Headlight: 12V 35/35W halogen.
Fuses: Main 15A, headlight 10A.

WARNING! Disconnect battery before electrical service to prevent short circuits.

Brake System

Front hydraulic disc brake and rear mechanical drum brake service procedures.

Front Brake: Check pad thickness (replace if less than 0.08 in/2mm), bleed system if spongy, use DOT 4 brake fluid.

Rear Brake: Adjust free play at lever, check shoe wear, replace if lining worn to wear indicator.

Suspension & Steering

Front fork oil capacity: 7.4 oz (220 ml) per leg, SAE 10W. Steering head bearing adjustment: No play but smooth movement.

Troubleshooting

Symptom	Possible Cause	Corrective Action
Engine won't start	Fuel, spark, compression	Check fuel flow, spark plug, compression (120+ psi)
Poor performance	Clogged air filter, carb issues	Clean air filter, check carburetor jets
Electrical failure	Battery, fuses, connections	Test battery voltage, check fuses, clean connections
Brake issues	Pads, fluid, adjustment	Inspect pads/shoes, check fluid level, adjust cables
Transmission problems	Oil level, clutch adjustment	Check oil level, adjust clutch free play

Technical Support: Contact authorized Yamaha dealer for complex repairs.

Parts: Use genuine Yamaha replacement parts for optimal performance.