Yamaha YZF-R125 Service Manual: Removing the cylinder head
1. Align:
- "I" mark "a" on the generator rotor (with the stationary pointer "b" on the generator cover)
a. Turn the crankshaft counterclockwise.
b. When the piston is at TDC on the compression stroke, align the "I" mark "c" on the camshaft sprocket with the mark "d" on the cylinder head.
2. Loosen:
- Camshaft sprocket bolt "1"
NOTE:
While holding the generator rotor nut with a wrench "2", loosen the camshaft sprocket bolt.
3. Remove:
- Camshaft sprocket
NOTE:
To prevent the timing chain from falling into the crankcase, fasten it with a wire "1".
4. Remove:
- Cylinder head
NOTE:
- Loosen the bolts in the proper sequence as shown.
- Loosen each bolt 1/2 of a turn at a time. After all of the bolts are fully loosened, remove bolts 1, 2, 4, and 6, and then remove the cylinder head with bolts 3 and 5 installed in the bolt holes.
Cylinder head
* Yamaha bond No. 1215 (Three Bond No. 1215) ...
Checking the cylinder head
1. Eliminate:
Combustion chamber carbon deposits
(with a rounded scraper)
NOTE:
Do not use a sharp instrument to avoid damaging
or scratching:
Spark plug bore threads
Valve seats
...
Other materials:
Owner's tool kit
Owner's tool kit
Owner's tool kit
Engine oil drain attachment
The owner's tool kit is located under the
rider seat.
The service information included in this
manual and the tools provided in the
owner's tool kit are intended to assist
you in the performance of preventive
maint ...
Electrical components
1. Main switch
2. Clutch switch
3. Front brake light switch
4. Ignition coil
5. Throttle body sensor assembly (intake air
pressure sensor, intake air temperature
sensor, throttle position sensor)
6. FID (fast idle solenoid)
7. Rectifier/regulator
8. Lean angle sensor
9. Starting circui ...
Installing the camshaft and rocker arms
1. Lubricate:
Rocker arms
Rocker arm shafts
2. Lubricate:
Camshaft
3. Install:
Camshaft "1"
NOTE:
Make sure that the camshaft projections "a" and
hole "b" are positioned as shown in the illustration.
4. Install:
Rocker arms
Rocker arm shafts "1"
NOTE:
Make ...