2002 YAMAHA XJ900S spark plugs replace

PERIODIC MAINTENANCE AND MINOR REPAIR
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Periodic maintenance and lubrication chart
NOTE:_

The annual checks must be performed every year, except if a kilometer-based maintenance is performed instead.


From 50,000 km, repeat the maintenance intervals starting from 10,000 km.


Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and techni-
cal skills.
_CP-03ENO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (×1,000 km)
ANNUAL
CHECK
1 10203040
1
*Fuel lineCheck fuel hoses for cracks or damage.√√√√ √
2*Fuel filterCheck condition.√√
3 Spark plugsCheck condition.
Clean and regap.√√
Replace.√√
4*ValvesCheck valve clearance.
Adjust.Every 20,000 km
5 Air filter elementClean.√√
Replace.√√
6ClutchCheck operation.
Adjust.√√√√√
7*Front brakeCheck operation, fluid level and vehicle for fluid leakage.
(See NOTE on page 6-4.)√√ √ √ √ √
Replace brake pads. Whenever worn to the limit
8*Rear brakeCheck operation, fluid level and vehicle for fluid leakage.
(See NOTE on page 6-4.)√√ √ √ √ √
Replace brake pads. Whenever worn to the limit
9*Brake hosesCheck for cracks or damage.√√√√ √
Replace. (See NOTE on page 6-4.) Every 4 years
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Checking the spark plugs The spark plugs are important engine
components, which should be checked
periodically, preferably by a Yamaha
dealer. Since heat and deposits will
cause any spark plug to slowly erode,
they should be removed and checked
in accordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plugs can re-
veal the condition of the engine.
The porcelain insulator around the cen-
ter electrode of each spark plug should
be a medium-to-light tan (the ideal col-
or when the motorcycle is ridden nor-
mally), and all spark plugs installed in
the engine should have the same color.
If any spark plug shows a distinctly dif-
ferent color, the engine could be defec-
tive. Do not attempt to diagnose such
problems yourself. Instead, have a
Yamaha dealer check the motorcycle.If a spark plug shows signs of electrode
erosion and excessive carbon or other
deposits, it should be replaced.
Before installing a spark plug, the spark
plug gap should be measured with a
wire thickness gauge and, if necessary,
adjusted to specification.
Clean the surface of the spark plug
gasket and its mating surface, and then
wipe off any grime from the spark plug
threads. Specified spark plug:
DPR8EA-9 (NGK) or
X24EPR-U9 (DENSO)
a. Spark plug gap
Spark plug gap:
0.8–0.9 mm
Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kgf)
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Troubleshooting chart
EW000125
WARNING
@ Keep away open flames and do not smoke while checking or working on the fuel system. @
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plugs
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gaps, or replace the spark plugs.
Have a Yamaha dealer check the vehicle.
The engine does not start.
Have a Yamaha dealer
check the vehicle.
The engine does not start.
Check the battery.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and charge the battery if necessary.
DryWet
Open the throttle halfway and operate
the electric starter.
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