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:
Adjusting the brake pedal free play
Adjusting the brake pedal free play
Brake pedal free play
The brake pedal free play should measure
3.5-4.5 mm (0.14-0.18 in) as
shown. Periodically check the brake
pedal free play and, if necessary, have
a Yamaha dealer adjust it.
WARNING
An incorrect brake pedal free play
in ...
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. ...
Catalytic converters
This vehicle is equipped with catalytic
converters in the exhaust system.
WARNING
The exhaust system is hot after operation.
To prevent a fire hazard or
burns:
Do not park the vehicle near
possible fire hazards such as
grass or other materials that
easily burn.
Park the vehic ...