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
Make sure there is sufficient gasoline in
the tank.
WARNING
Gasoline and gasoline vapors are
extremely flammable. To avoid fires
and explosions and to reduce the
risk of injury when refueling, follow
these instructions.
Before refueling, turn off the engine
and be sure that no on ...
Outline of the fi system
The main function of a fuel supply system is to provide fuel to the
combustion chamber at the optimum
air-fuel ratio in accordance with the engine operating conditions and the
atmospheric temperature. In
the conventional carburetor system, the air-fuel ratio of the mixture that is
supplied t ...
Checking the cylinder and piston
1. Check:
Piston wall
Cylinder wall
Vertical scratches Replace the
cylinder,
and replace the piston and piston rings as a
set.
2. Measure:
Piston-to-cylinder clearance
a. Measure cylinder bore "C" with the cylinder
bore gauge.
NOTE:
Measure cylinder bore "C" by takin ...