Checking The Ignition Spark Gap; Checking The Spark Plug Cap; Checking The Ignition Coil - Yamaha YZ250X 2022 Owner's Service Manual

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CHECKING THE IGNITION SPARK GAP

1. Check:
• Ignition spark gap
Out of specification  Perform the ignition
system troubleshooting, starting with step (3).
Refer to "TROUBLESHOOTING" on page
8-2.
Minimum ignition spark gap
6.0 mm (0.24 in)
TIP
If the ignition spark gap is within specification,
the ignition system circuit is operating normally.
a. Disconnect the spark plug cap from the
spark plug.
b. Connect the ignition checker "1" as
shown.
Ignition checker
90890-06754
Oppama pet–4000 spark checker
YM-34487
G089048
2. Spark plug cap
c. Kick the kickstarter crank.
d. Measure the ignition spark gap "a".
e. Crank the engine and gradually increase
the spark gap until a misfire occurs.
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CHECKING THE SPARK PLUG CAP

1. Remove:
• Spark plug cap
(from the high tension cord)
2. Check:
• Spark plug cap resistance
Out of specification  Replace.
Resistance
4.00–6.00 k
a. Connect the digital circuit tester () to the
spark plug cap.
ELECTRICAL COMPONENTS
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with tachom-
eter
YU-A1927
• Positive tester probe 
High tension cord terminal "1"
• Negative tester probe 
High tension cord terminal "2"
2
b. Measure the spark plug cap resistance.
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CHECKING THE IGNITION COIL

1. Check:
• Primary coil resistance
Out of specification  Replace.
Primary coil resistance
0.20–0.30 
a. Disconnect the ignition coil connectors
from the ignition coil terminals.
b. Connect the digital circuit tester () to the
ignition coil as shown.
Digital circuit tester (CD732)
90890-03243
Model 88 Multimeter with tachom-
eter
YU-A1927
• Positive tester probe 
Yellow "1"
• Negative tester probe 
Black "2"
8-8
1