Yamaha YZF-R125 Owners Manual: Checking the wheel bearings
The front and rear wheel bearings must be checked at the intervals specified in the periodic maintenance and lubrication chart. If there is play in the wheel hub or if the wheel does not turn smoothly, have a Yamaha dealer check the wheel bearings.
Checking the steering
Worn or loose steering bearings may
cause danger. Therefore, the operation
of the steering must be checked as follows
at the intervals specified in the periodic
maintenance and lubrication
c ...
Battery
A poorly maintained battery will corrode
and discharge quickly. The electrolyte
level, battery lead connections and
breather hose routing should be
checked before each ride and at the interval ...
Other materials:
Checking the primary driven gear
1. Check:
Primary driven gear "1"
Damage/wear Replace the
primary drive
gear and clutch housing as a set.
Excessive noise during operation
Replace
the primary drive gear and clutch housing as
a set.
...
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 timing chain tensioner rod,
wind it clockwise with a thin screwdriver "1" until
it stops.
b. ...
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
cylinder head.
3. Measure:
Valve seat width C "a"
Out of specification Replace
the ...