Yamaha YZF-R125 Service Manual: Checking the decompression system
1. Check:
- Decompression system
a. Check the decompression system with the camshaft sprocket and the decompression cam installed to the camshaft.
b. Check that the decompression lever "1" moves smoothly.
c. Without operating the decompression lever, check that the decompression cam "2" projects from the camshaft (exhaust cam) as shown in the illustration "A".
d. Move the decompression lever "1" in the direction of the arrow shown and check that the decompression cam does not project from the camshaft (exhaust cam) as shown in the illustration "B".
Checking the timing chain tensioner
1. Check:
Timing chain tensioner
Cracks/damage/rough movement Replace.
a. Lightly press the timing chain tensioner rod
into the timing chain tensioner housing by
hand.
NOTE:
While pressing the ...
Installing the cylinder head
1. Install:
Cylinder head
NOTE:
Pass the timing chain through the timing chain
cavity.
2. Tighten:
Cylinder head bolts "1"
Cylinder head bolts "2"
NOTE:
Lubricate the cylinder ...
Other materials:
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 ...
Adjusting the engine idling speed
NOTE:
Prior to adjusting the engine idling speed, the air
filter element should be clean, and the engine
should have adequate compression.
1. Start the engine and let it warm up for several
minutes.
2. Remove:
Rider seat
Refer to "GENERAL CHASSIS" on page 4-1.
3. Lift the fuel tank. ...
Checking the water pump
1. Check:
Water pump housing cover
Water pump housing
Cracks/damage Replace.
Impeller shaft
Cracks/damage/wear Replace.
Bearing
Rough movement Replace.
Radiator outlet hose
Cracks/damage Replace.
...