Yamaha YZF-R125 Service Manual: Charging system
Troubleshooting
The starter motor fails to turn.
NOTE:
Before troubleshooting, remove the following part(s):
1. Seats
2. Fuel tank
3. Left lower side cowling
4. Left upper side cowling
...
Circuit diagram
1. AC magneto
3. Rectifier/regulator
4. Main fuse
9. Battery ...
Other materials:
Chain drive
Removing the drive chain
1. Stand the vehicle on a level surface.
WARNINGSecurely support the vehicle so that there
is
no danger of it falling over.
NOTE:
Place the vehicle on a suitable stand so that the
rear wheel is elevated. ...
Removing the valves
The following procedure applies to all of the
valves and related components.
NOTE:
Before removing the internal parts of the cylinder
head (e.g., valves, valve springs, valve seats),
make sure the valves properly seal.
1. Check:
Valve sealing
Leakage at the valve seat Check
the valve
...
Faulty clutch
Clutch slips
1. Clutch
Improperly assembled clutch
Improperly adjusted clutch cable
Loose or fatigued clutch spring
Worn friction plate
Worn clutch plate
2. Engine oil
Incorrect oil level
Incorrect oil viscosity (low)
Deteriorated oil
Clutch drags
1. Clutch
Unevenly t ...