Yamaha 4TX-AE1, Service Manual

Page: 78 / 332

3-19
IGNITION TIMING CHECK
INSP
ADJ
NOTE:
NOTE:
IGNITION TIMING CHECK
Carburetor synchronization, engine idle speed
and throttle cable free play should be adjusted
properly before checking the ignition timing.
1. Remove:
Timing plug 1
2. Attach:
Timing light
Engine tachometer
(to the #1 spark plug lead)
Timing light:
90890-03141
Engine tachometer:
90890-03113
3. Check:
Ignition timing
Checking steps:
Start the engine and let it warm up. Let the en-
gine run at the specified speed.
Engine speed:
1,050 1,250 r / min
Visually check the stationary pointer a is with-
in the firing range b on the A.C. magneto.
Incorrect firing range
Check rotor and pick-
up assembly.
The ignition timing is not adjustable.
4. Install:
Timing plug