Yamaha YZF-R125 Service Manual: Checking the rear brake master cylinder
1. Check:
- Brake master cylinder
Damage/scratches/wear
Replace. - Brake fluid delivery passages
(brake master cylinder body)
Obstruction
Blow out with
compressed air.
2. Check:
Brake master cylinder kit
Damage/scratches/wear Replace.
3. Check:
- Brake fluid reservoir
Cracks/damage Replace.
- Brake fluid reservoir diaphragm
Cracks/damage Replace.
4. Check:
- Brake hoses
Cracks/damage/wear
Replace.
Removing the rear brake master cylinder
NOTE:
Before removing the rear brake master cylinder,
drain the brake fluid from the entire brake system.
1. Disconnect:
Rear brake light switch coupler
2. Loosen:
Rear brake light switc ...
Assembling the rear brake master cylinder
WARNING
Before installation, all internal brake components
should be cleaned and lubricated
with clean or new brake fluid.
Never use solvents on internal brake components.
...
Other materials:
Checking the friction plates
The following procedure applies to all of the friction
plates.
1. Check:
Friction plate
Damage/wear Replace the
friction plates
as a set.
2. Measure:
Friction plate thickness
Out of specification Replace
the friction
plates as a set.
NOTE:
Measure the friction plate ...
Starting failures
Engine
1. Cylinder and cylinder head
- Loose spark plug
- Loose cylinder head or cylinder
- Damaged cylinder head gasket
- Damaged cylinder gasket
- Worn or damaged cylinder
- Incorrect valve clearance
- Improperly sealed valve
- Incorrect valve-to-valve-seat contact
- Incorrect valve timi ...
Drive chain slack
The drive chain slack should be
checked before each ride and adjusted
if necessary.
To check the drive chain slack
Place the motorcycle on the sidestand.
TIP
When checking and adjusting the drive
chain slack, there should be no weight
on the motorcycle.
Shift the transmission in ...