Poor Braking Performance - Yamaha YJ50RN Service Manual

OVERHEATING/POOR BRAKING PERFORMANCE/
EAS00854
OVERHEATING
ENGINE
Cylinder head and piston
• Heavy carbon buildup
Engine oil and transmission oil
• Incorrect oil level
• Incorrect oil viscosity
• Inferior oil quality
FUEL SYSTEM
Carburetor
• Incorrect main jet setting
• Incorrect fuel level
• Damaged or loose carburetor joint
EAS00858

POOR BRAKING PERFORMANCE

• Worn brake shoe lining
• Worn or rusty brake drum
• Incorrect brake lever position
• Incorrect brake lever free play
• Incorrect brake camshaft lever position
EAS00862
UNSTABLE HANDLING
Handlebar
• Bent or improperly installed handlebar
Steering head components
• Improperly installed lower handlebar holder
• Improperly installed fork
(improperly tightened ring nut)
• Bent steering stem
• Damaged ball bearing or bearing race
Front shock absorber assembly (-ies)
• Faulty front shock absorber spring(s)
• Leaking oil
Rear shock absorber assembly
• Faulty rear shock absorber spring
• Leaking oil
UNSTABLE HANDLING
Air filter
• Clogged air filter element
CHASSIS
Brake(s)
• Dragging brake
ELECTRICAL SYSTEMS
Spark plug
• Incorrect spark plug gap
• Incorrect spark plug heat range
Ignition system
• Faulty ignitor unit
• Incorrect brake shoe position
• Damaged or fatigued brake shoe spring
• Oil or grease on the brake shoe
• Oil or grease on the brake drum
• Broken brake torque rod
Tire(s)
• Uneven tire pressures (front and rear)
• Incorrect tire pressure
• Uneven tire wear
Wheel(s)
• Incorrect wheel balance
• Deformed cast wheel
• Damaged wheel bearing
• Bent or loose wheel axle
• Excessive wheel runout
Frame
• Bent frame
• Damaged steering head pipe
• Improperly installed bearing race
8 - 3
TRBL
SHTG
8