Yamaha F100B - Checking the Ignition Timing

CHK
ADJ
Periodic checks and adjustments
3-11
60C5D11
3. Turn the throttle stop screw
2
in direc-
tion
a
or
b
until the specified engine
idle speed is obtained.
NOTE:
• To increase the idle speed, turn the throttle
stop screw in direction
a
.
• To decrease the idle speed, turn the throttle
stop screw in direction
b
.
4. After adjusting the idle speed, rev the
engine a few times and let it idle for at
least 15 seconds to check the stability of
the engine.
Checking the ignition timing
1. Start the engine and warm it up for 5 min-
utes.
2. Attach the special service tool to high-
tension cord #1, and then check the
engine idle speed.
3. Attach the special service tool to high-
tension cord #1
1
.
4. Check that the ignition timing mark (–5°)
a
on the flywheel magnet is aligned with
the pointer
b
. Check the ignition system
and ignition control system if necessary.
Digital tachometer: 90890-06760
Engine idle speed: 800–900 r/min
S60C3450
S60C3460
Timing light: 90890-03141
Ignition timing: ATDC 5°
S60C3470
S60C3480
S60C3490
-10
TDC
10
20
30