Overheating; Engine; Fuel System; Chassis - Yamaha YBR125ED 2005 Service Manual

OVERHEATING/POOR BRAKING PERFORMANCE/
EAS00854

OVERHEATING

ENGINE

Cylinder head and piston
• Heavy carbon buildup
Engine 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
Air filter
• Clogged air filter element
EAS00859

POOR BRAKING PERFORMANCE

Disc brake
• Worn brake pad
• Worn brake disc
• Air in hydraulic brake system
• Leaking brake fluid
• Faulty brake caliper kit
• Faulty brake caliper seal
• Loose union bolt
• Damaged brake hose
• Oil or grease on the brake disc
• Oil or grease on the brake pad
• Incorrect brake fluid level
EAS00861

FAULTY FRONT FORK LEGS

LEAKING OIL

• Bent, damaged or rusty inner tube
• Cracked or damaged outer tube
• Improperly installed oil seal
• Damaged oil seal lip
• Incorrect oil level (high)
• Loose damper rod bolt
• Damaged damper rod bolt copper washer
• Cracked or damaged cap bolt O-ring
FAULTY FRONT FORK LEGS

CHASSIS

Brake(s)
• Dragging brake

ELECTRICAL SYSTEMS

Spark plug
• Incorrect spark plug gap
• Incorrect spark plug heat range
Ignition system
• Faulty C.D.I unit
Drum brake
• Worn brake shoe
• Worn or rusty brake drum
• Incorrect brake pedal position (above the
top of the rider footrest)
• Incorrect brake pedal free play
• Incorrect brake camshaft lever position
• 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

MALFUNCTION

• Bent or damaged inner tube
• Bent or damaged outer tube
• Damaged fork spring
• Bent or damaged damper rod
• Incorrect oil viscosity
• Incorrect oil level
8 - 4
TRBL
SHTG