Yamaha YZF-R125 Service Manual: Starting circuit cut-off system operation
If the engine stop switch is set to "
" and the main switch is set to
"ON" (both switches are closed), the
starter motor can only operate if at least one of the following conditions is
met:
- The transmission is in neutral (the neutral switch is closed).
- The clutch lever is pulled to the handlebar (the clutch switch is closed) and the sidestand is up (the sidestand switch is closed).
The starting circuit cut-off relay prevents the starter motor from operating
when neither of these conditions
has been met. In this instance, the starting circuit cut-off relay is open so
current cannot reach the
starter motor. When at least one of the above conditions has been met, the
starting circuit cut-off relay
is closed and the engine can be started by pressing the start switch "
".
a. WHEN THE TRANSMISSION IS IN NEUTRAL
b. WHEN CLUTCH LEVER IS PULLED TO THE HANDLEBAR AND THE SIDESTAND IS UP
1. Battery
2. Main fuse
3. Main switch
4. Ignition fuse
5. Engine stop switch
6. Starting circuit cut-off relay
7. Clutch switch
8. Sidestand switch
9. Diode
10.Neutral switch
11.Start switch
12.Starter relay
13.Starter motor
Circuit diagram
4. Main fuse
5. Main switch
7. Clutch switch
8. Sidestand switch
9. Battery
10.Starter relay
11.Starter motor
12.Starting circuit cut-off relay
13.Diode
14.Neutral switch
16.Start switch ...
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
...
Other materials:
Checking the spark plug
The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic maintenance
and lubrication chart. In addition,
the condition of the ...
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. ...
Adjusting the exhaust gas volume
NOTE:
Be sure to set the CO density level to standard,
and then adjust the exhaust gas volume.
1. Remove:
Rider seat
Refer to "GENERAL CHASSIS" on page 4-1.
2. Set the main switch to "OFF".
3. Disconnect:
Self-diagnosis signal connector "1"
4. Connect:
FI diagnostic tool "2 ...