Poor Speed Performance; Overheating; Engine; Cooling System - Yamaha XF50W Service Manual

FAULTY CLUTCH/OVERHEATING/OVERCOOLING

POOR SPEED PERFORMANCE

V-belt
8Worn V-belt
8Oil or grease on the V-belt
Primary pulley weight(s)
8Faulty operation
8Worn primary pulley weight
Primary fixed sheave
8Worn primary fixed sheave
Primary sliding sheave
8Worn primary sliding sheave
Secondary fixed sheave
8Worn secondary fixed sheave
Secondary sliding sheave
8Worn secondary sliding sheave
EAS00855

OVERHEATING

ENGINE

Clogged coolant passages
8Heavy carbon buildup
Engine oil
8Incorrect oil level
8Incorrect oil viscosity
8Inferior oil quality

COOLING SYSTEM

Coolant
8Low coolant level
Radiator
8Damaged or leaking radiator
8Faulty radiator cap
8Bent or damaged radiator fan
Water pump
8Damaged or faulty water pump
Thermostat
8Thermostat stays closed
Oil cooler
8Clogged or damaged oil cooler
Hose(s) and pipe(s)
8Damaged hose
8Improperly connected hose
8Damaged pipe
8Improperly connected pipe

FUEL SYSTEM

Throttle body
8Damaged or loose throttle body joint
Air filter
8Clogged air filter element

CHASSIS

Brake(s)
8Dragging brake

ELECTRICAL SYSTEMS

Spark plug
8Incorrect spark plug gap
8Incorrect spark plug heat range
Ignition system
8Faulty coolant temperature sensor
8Faulty ECU
EAS00856
OVERCOOLING
COOLING SYSTEM
Thermostat
8Thermostat stays open
9-4
TRBL Q
SHTGl •