Yamaha YZF-R125 Service Manual: Checking the cooling system
1. Remove:
- Side covers
- Upper side cowlings Refer to "GENERAL CHASSIS" on page 4-1.
2. Check:
- Radiator "1"
- Radiator inlet hose "2"
- Radiator outlet hose "3"
Coolant reservoir hose "4"
Water pump breather hose "5" Cracks/damage → Replace.
Refer to "RADIATOR" on page 6-1.
3. Install:
- Upper side cowlings
- Side covers Refer to "GENERAL CHASSIS" on page 4-1.
Checking the coolant level
1. Stand the vehicle on a level surface.
NOTE:
Place the vehicle on a suitable stand.
Make sure the vehicle is upright.
2. Check:
Coolant level
The coolant level should be between the
max ...
Changing the coolant
1. Remove:
Lower side cowlings
Refer to "GENERAL CHASSIS" on page 4-1.
2. Remove:
Radiator cap "1"
WARNINGA hot radiator is under pressure.
Therefore,
do not remove t ...
Other materials:
Intake air temperature sensor
1. Check:
Intake air temperature sensor resistance
Out of specification Replace
the throttle
body.
a. Connect the pocket tester ( ×
1k) to the
throttle body sensor assembly coupler as
shown.
Positive tester probe
brown/white "1"
Negative tester probe
gray/black ...
Checking the primary driven gear
1. Check:
Primary driven gear "1"
Damage/wear Replace the
primary drive
gear and clutch housing as a set.
Excessive noise during operation
Replace
the primary drive gear and clutch housing as
a set.
...
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 ...