Yamaha YZF-R125 Service Manual: Adjusting the engine idling speed
NOTE:
Prior to adjusting the engine idling speed, the air filter element should be clean, and the engine should have adequate compression.
1. Start the engine and let it warm up for several minutes.
2. Remove:
- Rider seat Refer to "GENERAL CHASSIS" on page 4-1.
3. Lift the fuel tank. (Do not disconnect the fuel hose, fuel drain hose, and couplers.) Refer to "FUEL TANK" on page 7-1.
4. Install:
- Digital tachometer (onto the spark plug lead)
5. Check:
Engine idling speed
Out of specification → Adjust.
6. Remove:
- Right side panel Refer to "GENERAL CHASSIS" on page 4-1.
7. Adjust:
- Engine idling speed
a. Turn the pilot screw "1" in direction "a" or "b" until the specified engine idling speed is obtained.
8. Remove:
- Digital tachometer
9. Install:
- Fuel tank Refer to "FUEL TANK" on page 7-1.
- Right side panel
- Rider seat Refer to "GENERAL CHASSIS" on page 4-1.
10.Adjust:
- Throttle cable free play
Refer to "ADJUSTING THE THROTTLE CABLE
FREE PLAY" on page 3-6.
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" ...
Adjusting the throttle cable free play
NOTE:
Prior to adjusting the throttle cable free play, the
engine idling speed should be adjusted.
1. Check:
Throttle cable free play "a"
Out of specification →Adjust.
2. Remov ...
Other materials:
Cleaning and lubricating the drive chain
The drive chain must be cleaned and
lubricated at the intervals specified in
the periodic maintenance and lubrication
chart, otherwise it will quickly wear
out, especially when riding in dusty or
wet areas. Service the drive chain as
follows.
NOTICE
The drive chain must be lubricated
...
Checking the horn
1. Check:
Horn resistance
Out of specification Replace.
a. Disconnect the horn connectors from the
horn terminals.
b. Connect the pocket tester ( × 1) to the horn
terminals.
Positive tester probe
horn terminal "1"
Negative tester probe
horn terminal "2"
c. Measure t ...
Checking the speed sensor
1. Check:
Speed sensor output voltage
Out of specification → Replace.
a. Connect the pocket tester (DC 20 V) to the
speed sensor coupler (wire harness end) as
shown.
Positive tester probe
gray "1"
Negative tester probe
gray/black "2"
b. Set the main switch to "ON".
c. ...