Yamaha YZF-R125 Service Manual: Checking the thermostat
1. Check:
- Thermostat
Does not open at 80.5-83.5 C (176.9-182.3
F)
Replace.
a. Suspend the thermostat "1" in a container "2" filled with water.
b. Slowly heat the water "3".
c. Place a thermometer "4" in the water.
d. While stirring the water, observe the thermostat and thermometer's indicated temperature.
A. Fully closed
B. Fully open
NOTE:
If the accuracy of the thermostat is in doubt, replace it. A faulty thermostat could cause serious overheating or overcooling.
2. Check:
- Thermostat cover
Cracks/damage
Replace.
3. Check:
- Radiator inlet hose
Cracks/damage
Replace.
Thermostat
...
Installing the thermostat
1. Install:
Thermostat
NOTE:
Install the thermostat with its breather hole "a"
facing up.
2. Install:
Copper washer
Coolant temperature sensor
CAUTION:Use extreme care when ...
Other materials:
Checking the fuel pressure
1. Check:
Pressure regulator operation
a. Remove the fuel hose connector cover "1"
and disconnect the fuel hose "2" from the fuel
pump.
CAUTION:Although the fuel has been removed from
the fuel tank, be careful when removing the
fuel hose, since there may be fuel remaining
i ...
Assembling the crankcase
1. Thoroughly clean all the gasket mating surfaces
and crankcase mating surfaces.
2. Apply:
Sealant
(onto the crankcase mating surfaces)
NOTE:
Do not allow any sealant to come into contact
with the oil gallery.
3. Install:
Right crankcase
NOTE:
Turn the shift drum segment ...
Checking the primary drive gear
1. Remove:
Primary drive gear
Refer to "BALANCER GEAR" on page 5-53.
2. Check:
Primary drive gear
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
...