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PERIODIC MAINTENANCE AND MINOR REPAIR
6-3
6
9*WheelsCheck runout, spoke tightness and for damage.
Tighten spokes if necessary.√√√√√
10*TiresCheck tread depth and for damage.
Replace if necessary.
Check air pressure.
Correct if necessary.√√√√ √
11*Wheel bearingsCheck bearing for looseness or damage.√√√√
12*SwingarmCheck operation and for excessive play.√√√√
13 Drive chainCheck chain slack, alignment and condition.
Adjust and lubricate chain with a special O-ring chain lu-
bricant thoroughly.Every 500 km and after washing the motorcycle or
riding in the rain
14*Steering bearingsCheck bearing play and steering for roughness.√√√√√
Lubricate with lithium-soap-based grease. Every 20000 km
15*Chassis fastenersMake sure that all nuts, bolts and screws are properly
tightened.√√√√ √
16 SidestandCheck operation.
Lubricate.√√√√ √
17*Sidestand switchCheck operation.√√√√√ √
18*Front forkCheck operation and for oil leakage.√√√√
19*Shock absorber assem-
blyCheck operation and shock absorber for oil leakage.√√√√
20*Rear suspension relay
arm and connecting
arm pivoting pointsCheck operation.√√√√
21*Fuel injectionAdjust engine idling speed.√√√√√ √
22 Engine oilChange.
Check oil level and vehicle for oil leakage.√√√√√ √ NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (× 1000 km)
ANNUAL
CHECK
1 10203040
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-4
6
EAUM1890
NOTE:
Replace the air filter element more frequently if you are riding in unusually wet or dusty areas.
Hydraulic brake service
Regularly check and, if necessary, correct the brake fluid level.
Every two years replace the internal components of the brake master cylinder, and change the brake fluid.Replace the brake hoses every four years and if cracked or damaged.
23 Engine oil filter elementReplace.√√√
24*Cooling systemCheck coolant level and vehicle for coolant leakage.√√√√ √
Change. Every 3 years
25*Front and rear brake
switchesCheck operation.√√√√√ √
26Moving parts and ca-
blesLubricate.√√√√ √
27*Throttle grip housing
and cableCheck operation and free play.
Adjust the throttle cable free play if necessary.
Lubricate the throttle grip housing and cable.√√√√ √
28*Air induction systemCheck the air cut-off valve, reed valve, and hose for dam-
age.
Replace the entire air induction system if necessary.√√√√ √
29*Mufflers and exhaust
pipesCheck the screw clamps for looseness.√√√√√ √
30*Lights, signals and
switchesCheck operation.
Adjust headlight beam.√√√√√ √ NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (× 1000 km)
ANNUAL
CHECK
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Page 43 of 92
PERIODIC MAINTENANCE AND MINOR REPAIR
6-5
6
EAU18712
Removing and installing cowl-
ings and panels The cowlings and panels shown need
to be removed to perform some of the
maintenance jobs described in this
chapter. Refer to this section each time
a cowling or panel needs to be re-
moved and installed.
XT660RXT660X
XT660RXT660X
XT660R1. Cowling A
1. Cowling A
1. Panel A
1
1. Panel A
1. Cowling B
2. Panel B
1
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Page 44 of 92
PERIODIC MAINTENANCE AND MINOR REPAIR
6-6
6XT660X
EAUM1682
Cowling A
To remove the cowlingRemove the bolts and spacers, and
then lift the cowling up to remove it.XT660R
XT660X
To install the cowling
1. Place the cowling bracket tab be-
tween the protector and the brack-
et on each side.2. Place the cowling in the original
position, and then install the bolts
and spacers.
EAUM1692
Cowling B (XT660R)
To remove the cowling1. Remove the seat and panel B.
(See pages 3-12 and 6-5.)
2. Remove the bolts, and then re-
move the quick fastener screws by
turning them 1/4 turn counterclock-
wise.
3. Pull the cowling off at the area
shown.
1. Cowling B
2. Panel B
2
1
1. Bolt
1. Bolt
1
1. Protector
2. Cowling bracket tab
3. Bracket
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Page 45 of 92
PERIODIC MAINTENANCE AND MINOR REPAIR
6-7
6 To install the cowling
1. Place the cowling in the original
position, and then install the quick
fastener screws and the bolts.
2. Install the panel.
3. Install the seat.
EAUM2130
Cowling B (XT660X)
To remove the cowling1. Remove the seat and panel B.
(See pages 3-12 and 6-5.)
2. Remove the bolts, and then re-
move the quick fastener screw by
turning it 1/4 turn counterclock-
wise.
3. Pull the cowling off at the area
shown.
To install the cowling1. Place the cowling in the original
position, and then install the quick
fastener screw and the bolts.2. Install the panel.
3. Install the seat.
EAUM1701
Panel A
To remove the panel1. Remove the seat. (See page
3-12.)
2. Remove the bolts and the spacer,
and then pull the panel off at the
area shown.
1. Bolt
2. Quick fastener screw
1. Bolt
2. Quick fastener screw1
2
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Page 46 of 92
PERIODIC MAINTENANCE AND MINOR REPAIR
6-8
6To install the panel
1. Place the panel in the original posi-
tion, install spacer, and then install
the bolts.
2. Install the seat.
EAUM1710
Panel B
To remove the panel1. Remove the seat. (See page
3-12.)
2. Remove the bolt, and then pull the
panel off at the areas shown.
To install the panel1. Place the panel in the original posi-
tion, and then install the bolt.2. Install the seat.
1. Bolt
2. Spacer
1. Bolt
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-9
6
EAU19603
Checking the spark plug The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plug can re-
veal the condition of the engine.
To remove the spark plug
1. Remove the spark plug cap.
2. Remove the spark plug as shown,
with the spark plug wrench includ-
ed in the owner’s tool kit.To check the spark plug
1. Check that the porcelain insulator
around the center electrode of the
spark plug is a medium-to-light tan
(the ideal color when the vehicle is
ridden normally).
NOTE:
If the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer checkthe vehicle.2. Check the spark plug for electrode
erosion and excessive carbon or
other deposits, and replace it if
necessary.
To install the spark plug
1. Measure the spark plug gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifica-
tion.
1. Spark plug cap
1. Spark plug wrench
Specified spark plug:
NGK/CR7E
1. Spark plug gap
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-10
62. Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
3. Install the spark plug with the
spark plug wrench, and then tight-
en it 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 1/4–1/2 turn
past finger tight. However, the spark
plug should be tightened to the speci-fied torque as soon as possible.
4. Install the spark plug cap.
EAUM1841
Engine oil and oil filter ele-
ment The engine oil level should be checked
before each ride. In addition, the oil
must be changed and the oil filter ele-
ment replaced at the intervals specified
in the periodic maintenance and lubri-
cation chart.
To check the engine oil level
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion.NOTE:
Make sure that the vehicle is positioned
straight up when checking the oil level.
A slight tilt to the side can result in afalse reading.
2. Start the engine, warm it up for 10–
15 minutes, and then turn it off.
3. Wait a few minutes until the oil set-
tles, remove the oil filler cap, wipe
the dipstick clean, insert it back
into the oil filler hole (without
screwing it in), and then remove it
again to check the oil level.
NOTE:
The engine oil tank is located in-
side of the frame.
The engine oil should be between
the minimum and maximum levelmarks.
CAUTION:
ECA10010
Do not operate the vehicle until you
know that the engine oil level is suf-ficient.
Tightening torque:
Spark plug:
12.5 Nm (1.25 m·kgf, 9.0 ft·lbf)
1. Engine oil filler cap
2. Maximum level mark
3. Minimum level mark
U5VKE1E0.book Page 10 Tuesday, July 18, 2006 1:00 PM