Yamaha YZF-R125 Service Manual: Checking the valve springs
The following procedure applies to all of the valve springs.
1. Measure:
- Valve spring free length "a"
Out of specification Replace the valve
spring.
2. Measure:
- Compressed valve spring force "a"
Out of specification Replace the valve
spring.
b. Installed length
3. Measure:
- Valve spring tilt "a"
Out of specification
Replace the
valve spring.
Checking the valve seats
The following procedure applies to all of the
valves and valve seats.
1. Eliminate:
Carbon deposits
(from the valve face and valve seat)
2. Check:
Valve seat
Pitting/wear Replace the ...
Installing the valves
The following procedure applies to all of the
valves and related components.
1. Deburr:
Valve stem end
(with an oil stone)
2. Lubricate:
Valve stem "1"
Valve stem seal "2"
(with ...
Other materials:
Checking the front brake hose
1. Check:
Brake hose "1"
Cracks/damage/wear
Replace.
2. Check:
Brake hose holder "2"
Loose connection Tighten the
holder bolt.
3. Hold the vehicle upright and apply the front
brake several times.
4. Check:
Brake hose
Brake fluid leakage Replace the
da ...
Engine oil and oil filter element
The engine oil level should be checked
before each ride. In addition, the oil
must be changed and the oil filter element
replaced at the intervals specified
in the periodic maintenance and lubrication
chart.
To check the engine oil level
Place the vehicle on a level surface
and hol ...
Checking the brake fluid level
Front brake
Front brake
Minimum level mark
Rear brake
Rear brake
Minimum level mark
Insufficient brake fluid may allow air to
enter the brake system, possibly causing
it to become ineffective.
Before riding, check that the brake fluid
is above the minimum level mark an ...