spark plugs replace YAMAHA XJ900S 2000 Owners Manual

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PERIODIC MAINTENANCE AND LUBRICATION
CP-01ENO. ITEM CHECKS AND MAINTENANCE JOBSINITIAL
(1,000 km)EVERY
6,000 km
or
6 months
(whichever
comes first)12,000 km
or
12 months
(whichever
comes first)
1
*Fuel line• Check fuel hoses for cracks or damage.
• Replace if necessary.ÖÖ
2*Fuel filter• Check condition.
• Replace if necessary.Ö
3 Spark plugs• Check condition.
• Clean, regap or replace if necessary.ÖÖÖ
4*Valves• Check valve clearance.
• Adjust if necessary.Every 24,000 km or 24 months
(whichever comes first)
5 Air filter• Clean or replace if necessary.ÖÖ
6Clutch• Check operation.
• Adjust or replace cable.ÖÖÖ
7*Front brake• Check operation, fluid level and vehicle for fluid leakage.
(See NOTE on page 6-4.)
• Correct accordingly.
• Replace brake pads if necessary.ÖÖÖ
8*Rear brake• Check operation, fluid level and vehicle for fluid leakage.
(See NOTE on page 6-4.)
• Correct accordingly.
• Replace brake pads if necessary.ÖÖÖ
9*Wheels• Check balance, runout and for damage.
• Rebalance or replace if necessary.ÖÖ
10*Tires• Check tread depth and for damage.
• Replace if necessary.
• Check air pressure.
• Correct if necessary.ÖÖ

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Spark plug inspectionThe spark plug is an important engine
component and should be inspected
periodically, preferably by a Yamaha
dealer. The condition of the spark plug
can indicate the condition of the en-
gine.
Normally, all spark plugs from the
same engine should have the same
color on the white insulator around the
center electrode. The ideal color at this
point is a medium-to-light tan color for a
motorcycle that is being ridden normal-
ly. If one spark plug shows a distinctly
different color, there could be some-
thing wrong with the engine.Do not attempt to diagnose such prob-
lems yourself. Instead, take the motor-
cycle to a Yamaha dealer. The spark
plugs should be periodically removed
and inspected because heat and de-
posits will cause any spark plug to
slowly break down and erode. If elec-
trode erosion becomes excessive, or if
carbon and other deposits are exces-
sive, the spark plug should be replaced
with the specified plug.
Before installing any spark plug, mea-
sure the electrode gap with a wire
thickness gauge and adjust it to specifi-
cation.When installing a spark plug, the gas-
ket surface should always be cleaned
and a new gasket used. Any grime
should be wiped off from the threads
and the spark plug tightened to the
specified torque.
NOTE:@ If a torque wrench is not available when
installing a spark plug, a good estimate
of the correct torque is 1/4 to 1/2 turn
past finger tight. The spark plug should
be tightened to the specified torque as
soon as possible. @
a. Spark plug gap
Specified spark plug:
DPR8EA-9 (NGK) or
X24EPR-U9 (DENSO)
Spark plug gap:
0.8 ~ 0.9 mm
Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kg)

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Troubleshooting chart
EW000125
WARNING
@ Never check the fuel system while smoking or in the vicinity of an open flame. @
Check if there is fuel
in the fuel tank.1. Fuel
Enough fuel.
No fuel.
Go to compression check.
Supply fuel.
Use the electric starter.2. Compression
There is compression.
No compression.
Go to ignition check.
Ask a Yamaha dealer to
inspect.
Remove spark
plugs and
check electrodes.3. Ignition
Wet.
Dry.
Wipe clean with dry cloth and correct
spark gap or replace spark plug.
Ask a Yamaha dealer to inspect.
Engine doesn't start, go to battery
check.Open throttle half-way and start
the engine.
Use the electric starter.4. Battery
Engine turns over
quickly.
Engine turns over
slowly.
Battery good.Check connections or
recharge.
Engine doesn't start, ask a Yamaha
dealer to inspect.
Engine doesn't start, go to compression check.