Yamaha YZF-R125 Service Manual: Engine
- Engine removal
- Cylinder head
- Removing the cylinder head
- Checking the cylinder head
- Checking the camshaft sprocket and timing chain guide
- Checking the timing chain tensioner
- Checking the decompression system
- Installing the cylinder head
- Camshaft
- Checking the camshaft
- Checking the rocker arms and rocker arm shafts
- Installing the camshaft and rocker arms
- Valves and valve springs
- Removing the valves
- Checking the valves and valve guides
- Checking the valve seats
- Checking the valve springs
- Installing the valves
- Cylinder and piston
- Removing the piston
- Checking the cylinder and piston
- Checking the piston rings
- Checking the piston pin
- Installing the piston and cylinder
- Generator and starter clutch
- Removing the generator
- Removing the starter clutch
- Checking the starter clutch
- Installing the starter clutch
- Installing the generator
- Electric starter
- Clutch
- Removing the clutch
- Checking the friction plates
- Checking the clutch plates
- Checking the clutch springs
- Checking the clutch housing
- Checking the clutch boss
- Checking the primary drive gear
- Checking the primary driven gear
- Installing the clutch
- Oil pump
- Shift shaft
- Balancer gear
- Removing the primary drive gear and balancer gears
- Checking the balancer gears and primary drive gear
- Installing the primary drive gear and balancer gears
- Crankcase
- Separating the crankcase
- Checking the crankcase
- Checking the timing chain and timing chain guide
- Checking the bearings and oil seal
- Installing the bearing retainer
- Assembling the crankcase
- Crankshaft
- Transmission
Installing the drive chain
1. Lubricate:
Drive chain
Master link
2. Install:
Drive sprocket
Drive sprocket retainer bolts
3. Install:
Master link
O-rings
Master link plate
Master link clip "1"
...
Engine removal
...
Other materials:
Fuel tank cap
Fuel tank cap
Fuel tank cap lock cover
Unlock.
To remove the fuel tank cap
Open the fuel tank cap lock cover.
Insert the key into the lock and turn
it 1/4 turn counterclockwise. The
lock will be released and the fuel
tank cap can be removed.
To install the fuel tank ca ...
Troubleshooting
Although Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur during
operation. Any problem in the fuel,
compression, or ignition systems, for
example, can cause poor starting and
loss of power.
The following troubleshooting charts
repre ...
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 ...