Yamaha YZF-R125 Service Manual: Fuel system
Installing the water pump
1. Install:
Water pump assembly "1"
O-rings "2"
NOTE:
Align the projection "a" on the impeller shaft
with the slit "b" on the camshaft sprocket bolt.
Lubricate the O-rings with a thi ...
Fuel tank
...
Other materials:
Checking the piston rings
1. Measure:
Piston ring side clearance
Out of specification Replace the
piston
and piston rings as a set.
NOTE:
Before measuring the piston ring side clearance,
eliminate any carbon deposits from the piston
ring grooves and piston rings.
2. Install:
Piston ring
(into the cylind ...
Checking the clutch housing
1. Check:
Clutch housing dogs "1"
Damage/pitting/wear
Deburr the clutch
housing dogs or replace the clutch housing.
NOTE:
Pitting on the clutch housing dogs will cause erratic
clutch operation.
2. Check:
Bearing
Damage/wear Replace the
bearing and
clutch housin ...
Incorrect engine idling speed
Engine
1. Cylinder and cylinder head
Incorrect valve clearance
Damaged valve train components
2. Air filter
Clogged air filter element
Fuel system
1. Throttle body
Damaged or loose throttle body joint
Improperly adjusted engine idling speed (idle
adjusting screw)
Improper ...