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 stator coil
1. Disconnect:
Stator coil coupler
(from the wire harness)
2. Check:
Stator coil resistance
Out of specification → Replace the
crankshaft
position sensor/stator assembly.
a. Connect the pocket tester ( ×
1) to the stator
coil coupler as shown.
b. Measure the sta ...
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 ...
Troubleshooting
Although Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur during
operation. Any problem in the fuel,
compression, or ignition systems, for
example, can cause poor starting and
loss of power.
The following troubleshooting charts
repre ...