Removing The Balancer; Checking The Primary Drive Gear, Balancer Shaft Drive Gear, And Balancer Weight Gear; Checking The Balancer; Checking The Oil Pump - Yamaha WR250F 2016 Owner's Service Manual

REMOVING THE BALANCER

EAS2GB7299
1. Loosen:
• Balancer nut "1"
• Primary drive gear nut "2"
• Balancer weight gear nut "3"
TIP
Place an aluminum plate "a" between the teeth
of the balancer drive gear "4" and balancer
weight gear "5".
1
4
2
a
4
CHECKING THE PRIMARY DRIVE GEAR,
EAS2GB7300
BALANCER SHAFT DRIVE GEAR, AND
BALANCER WEIGHT GEAR
1. Check:
• Primary drive gear "1"
• Balancer shaft drive gear "2"
• Balancer weight gear "3"
Wear/damage  Replace.
OIL PUMP AND BALANCER GEAR
5
a
3
5
6-58

CHECKING THE BALANCER

EAS2GB7301
1. Check:
• Balancer
Crack/damage  Replace.

CHECKING THE OIL PUMP

EAS2GB7302
1. Check:
• Oil pump drive gear
• Oil pump driven gear
• Oil pump housing
• Oil pump housing cover
Cracks/damage/wear  Replace the defec-
tive part(s).
2. Measure:
• Inner-rotor-to-outer-rotor-tip clearance "a"
• Outer-rotor-to-oil-pump-housing clearance
"b"
• Oil-pump-housing-to-inner-rotor-and-outer-
rotor clearance "c"
Out of specification  Replace the oil pump.