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6-6
6 To install the panel
1. Place the panel in the original po-
sition, and then install the screws.
2. Install the seat.
EAU01880
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.a. Spark plug gap
Specified spark plug:
CR8E (NGK) or
U24ESR-N (DENSO)
Spark plug gap:
0.7–0.8 mm
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6-7
6Clean the surface of the spark plug
gasket and its mating surface, and then
wipe off any grime from the spark plug
threads.
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. @
EAU02938
Engine oil and oil filter
cartridge The engine oil level should be checked
before each ride. In addition, the oil
must be changed and the oil filter car-
tridge replaced at the intervals speci-
fied in the periodic maintenance and
lubrication chart.
To check the engine oil level
1. Place the motorcycle on the cen-
terstand.
NOTE:@ Make sure that the motorcycle is posi-
tioned straight up when checking the oil
level. A slight tilt to the side can result in
a false reading. @2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Wait a few minutes until the oil set-
tles, and then check the oil level
through the check window located
at the bottom-right side of the
crankcase.NOTE:@ The engine oil should be between the
minimum and maximum level marks. @4. If the engine oil is below the mini-
mum level mark, add sufficient oil
of the recommended type to raise
it to the correct level. Tightening torque:
Spark plug:
12.5 Nm (1.25 m·kg)
1. Engine oil level window
2. Maximum level mark
3. Minimum level mark
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-10
6
EC000072
CAUTION:@ l
In order to prevent clutch slip-
page (since the engine oil also
lubricates the clutch), do not
mix any chemical additives with
the oil or use oils of a higher
grade than “CD”. In addition, do
not use oils labeled “ENERGY
CONSERVING II” or higher.
l
Make sure that no foreign mate-
rial enters the crankcase.
@9. Start the engine, and then let it idle
for several minutes while checking
it for oil leakage. If oil is leaking,
immediately turn the engine off
and check for the cause.NOTE:@ After the engine is started, the engine
oil level warning light should go off if the
oil level is sufficient. @
EC000067
CAUTION:@ If the oil level warning light flickers
or remains on, immediately turn the
engine off and have a Yamaha deal-
er check the vehicle. @10. Turn the engine off, and then
check the oil level and correct it if
necessary.
EAU02928
Cleaning the air filter element The air filter element should be cleaned
at the intervals specified in the periodic
maintenance and lubrication chart.
Clean the air filter element more fre-
quently if you are riding in unusually
wet or dusty areas.
1. Remove the seat. (See page 3-12
for seat removal and installation
procedures.)
2. Turn the fuel cock lever to “ON”,
and then remove the fuel cock le-
ver by removing the screw.1. Screw
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-12
6 7. Lightly tap the air filter element to
remove most of the dust and dirt,
and then blow the remaining dirt
out with compressed air as shown.
If the air filter element is damaged,
replace it.
8. Insert the air filter element into the
air filter case.
EC000082
CAUTION:@ l
Make sure that the air filter ele-
ment is properly seated in the
air filter case.
l
The engine should never be op-
erated without the air filter ele-
ment installed, otherwise the
piston(s) and/or cylinder(s) may
become excessively worn.
@9. Install the air filter case cover by
installing the screws.
10. Install the fuel tank by installing the
bolts.
11. Connect the hoses.
12. Install the fuel cock lever by install-
ing the screw.
13. Install the seat.
EAU00630
Adjusting the carburetors The carburetors are important parts of
the engine and require very sophisti-
cated adjustment. Therefore, most car-
buretor adjustments should be left to a
Yamaha dealer, who has the neces-
sary professional knowledge and expe-
rience. The adjustment described in
the following section, however, may be
serviced by the owner as part of routine
maintenance.
EC000095
CAUTION:@ The carburetors have been set and
extensively tested at the Yamaha
factory. Changing these settings
without sufficient technical knowl-
edge may result in poor perfor-
mance of or damage to the engine. @
1. Air filter element
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-19
6
EAU00713
Adjusting the rear brake light
switch The rear brake light switch, which is ac-
tivated by the brake pedal, is properly
adjusted when the brake light comes
on just before braking takes effect. If
necessary, adjust the brake light switch
as follows.
Turn the adjusting nut while holding the
rear brake light switch in place. To
make the brake light come on earlier,
turn the adjusting nut in direction
a. To
make the brake light come on later,
turn the adjusting nut in direction
b.
EAU00721
Checking the front and rear
brake pads The front and rear brake pads must be
checked for wear at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
EAU00725
Front brake pads
Each front brake pad is provided with a
wear indicator groove, which allows
you to check the brake pad wear with-
out having to disassemble the brake.
To check the brake pad wear, check
the wear indicator groove. If a brake
pad has worn to the point that the wear
indicator groove has almost disap-
peared, have a Yamaha dealer replace
the brake pads as a set.
1. Brake light switch
2. Brake light switch adjusting nut
1. Wear indicator groove (´ 2)Front
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6-29
6
EAU01470
Replacing the fuses The fuse box is located under the seat.
(See page 3-12 for seat removal and
installation procedures.)
If a fuse is blown, replace it as follows.
1. Turn the key to “OFF” and turn off
the electrical circuit in question.
2. Remove the blown fuse, and then
install a new fuse of the specified
amperage.
EC000103
CAUTION:@ Do not use a fuse of a higher amper-
age rating than recommended to
avoid causing extensive damage to
the electrical system and possibly a
fire. @3. Turn the key to “ON” and turn on
the electrical circuit in question to
check if the device operates.
4. If the fuse immediately blows
again, have a Yamaha dealer
check the electrical system.
1. Fuse box
1. Main fuse
2. Ignition fuse
3. Signaling system fuse
4. Headlight fuse
5. Hazard fuse
6. Spare fuse (´ 3)
Specified fuses:
Main fuse: 30 A
Ignition fuse: 10 A
Signaling system fuse: 15 A
Headlight fuse: 15 A
Hazard fuse: 10 A
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-30
6
EAU00829
Replacing a headlight bulb
(for XJ600S)This motorcycle is equipped with
quartz bulb headlights. If a headlight
bulb burns out, replace it as follows.
1. Disconnect the headlight coupler,
and then remove the headlight
bulb cover.2. Unhook the headlight bulb holder,
and then remove the defective
bulb.
EW000119
WARNING
@ Headlight bulbs get very hot. There-
fore, keep flammable products away
from a lit headlight bulb, and do not
touch the bulb until it has cooled
down. @
3. Place a new bulb into position, and
then secure it with the bulb holder.
EC000105
CAUTION:@ Do not touch the glass part of the
headlight bulb to keep it free from
oil, otherwise the transparency of
the glass, the luminosity of the bulb,
and the bulb life will be adversely af-
fected. Thoroughly clean off any dirt
and fingerprints on the headlight
bulb using a cloth moistened with
alcohol or thinner. @
1. Headlight coupler
2. Headlight bulb cover
1. Headlight bulb holder
1. Do not touch this area.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-31
64. Install the bulb cover, and then
connect the coupler.
5. Have a Yamaha dealer adjust the
headlight beam if necessary.
EAU03188
Replacing the headlight bulb
(for XJ600N)This motorcycle is equipped with a
quartz bulb headlight. If the headlight
bulb burns out, replace it as follows.
1. Remove the headlight unit by re-
moving the screws.2. Disconnect the headlight coupler,
and then remove the headlight unit
and bulb cover.1. Screw (´ 2)
1. Headlight coupler
2. Headlight bulb cover
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