Yamaha YZF-R125 Service Manual: Circuit diagram
4. Main fuse
5. Main switch
6. Radiator fan motor fuse
9. Battery
22.Coolant temperature sensor
32.Radiator fan motor relay
33.Radiator fan motor
59.Coolant temperature warning light
64.Ignition fuse
66.Signaling system fuse
Cooling system
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Troubleshooting
NOTE:
Before troubleshooting, remove the following part(s):
1. Rider seat
2. Fuel tank
3. Right upper side cowling
4. Passenger seat
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Other materials:
Checking the timing chain and timing chain guide
1. Check:
Timing chain
Damage/stiffness Replace the
timing
chain and camshaft sprocket as a set.
2. Check:
Timing chain guide (intake side)
Damage/wear Replace.
Checking the oil strainer
1. Check:
Oil strainer
Damage Replace.
Contaminants Clean with solvent.
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Starting failures
Engine
1. Cylinder and cylinder head
- Loose spark plug
- Loose cylinder head or cylinder
- Damaged cylinder head gasket
- Damaged cylinder gasket
- Worn or damaged cylinder
- Incorrect valve clearance
- Improperly sealed valve
- Incorrect valve-to-valve-seat contact
- Incorrect valve timi ...
Checking the shift shaft
1. Check:
Shift shaft
Bends/damage/wear Replace.
Shift shaft spring
Damage/wear Replace.
Checking the stopper lever
1. Check:
Stopper lever
Bends/damage Replace.
Roller turns roughly Replace
the stopper
lever.
Stopper lever spring
Damage/wear Replace.
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