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"
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Engine removal
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Other materials:
Removing the starter clutch
1. Remove:
Starter clutch bolts "1"
NOTE:
While holding the generator rotor "2" with the
sheave holder "3", remove the starter clutch
bolts.
Do not allow the sheave holder to touch the
projection on the generator rotor.
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Checking the speed sensor
1. Check:
Speed sensor output voltage
Out of specification → Replace.
a. Connect the pocket tester (DC 20 V) to the
speed sensor coupler (wire harness end) as
shown.
Positive tester probe
gray "1"
Negative tester probe
gray/black "2"
b. Set the main switch to "ON".
c. ...
Installing the front wheel (disc)
1. Install:
Front brake disc
NOTE:
Be sure to install the front brake disc with the
arrow mark "a" on the disc facing out.
Tighten the brake disc bolts in stages and in a
crisscross pattern.
2. Check:
Front brake disc
Refer to "CHECKING THE FRONT BRAKE
DISC" on page 4 ...