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PERIODIC MAINTENANCE AND MINOR REPAIR
6-6
6
EAU03329
Checking the spark plugs The spark plugs are important engine
components, which are easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plugs 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.
To remove a 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 plugs
1. Check that the porcelain insulator
around the center electrode on
each spark plug is a medi-
um-to-light tan (the ideal color
when the motorcycle is ridden nor-
mally).
2. Check that all spark plugs installed
in the engine have the same color.
NOTE:_ 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. _3. Check each spark plug for elec-
trode erosion and excessive car-
bon or other deposits, and replace
it if necessary.
1. Spark plug cap
1. Spark plug wrench
Specified spark plug:
DPR8EA-9 (NGK) or
X24EPR-U9 (DENSO)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-7
6To install a spark plug
1. Measure the spark plug gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifica-
tion.
2. Clean the surface of the spark
plug gasket and its mating sur-
face, 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.
EAU03759
Engine oil and oil filter
element 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 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.
a. Spark plug gapSpark plug gap:
0.8–0.9 mm
Tightening torque:
Spark plug:
17.5 Nm (1.75 m·kg)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-8
6 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.To change the engine oil (with or
without oil filter element replace-
ment)
1. Start the engine, warm it up for
several minutes, and then turn it
off.
2. Place an oil pan under the engine
to collect the used oil.
3. Remove the engine oil filler cap
and drain bolt to drain the oil from
the crankcase.
NOTE:_ Skip steps 4–8 if the oil filter element is
not being replaced. _4. Remove the oil filter element drain
screw to drain the oil from the oil
filter element.
5. Remove the oil filter element cover
by removing the bolt.
1. Engine oil level check window
2. Maximum level mark
3. Minimum level mark
1. Engine oil drain bolt
1. Oil filter element drain screw
2. Bolt
3. Oil filter element cover
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-9
66. Remove and replace the oil filter
element and O-ring.7. Install the oil filter element cover
by aligning the projection on the
cover with the slot in the crank-
case, installing the bolt, then tight-
ening it to the specified torque.
NOTE:_ Make sure that the O-ring is properly
seated. _
8. Install the oil filter element drain
screw, and then tighten it to the
specified torque.
9. Install the engine oil drain bolt, and
then tighten it to the specified
torque.
10. Add the specified amount of the
recommended engine oil, and
then install and tighten the oil filler
cap.
1. Oil filter element
2. O-ring (´ 2)
1. Projection
2. Slot
Tightening torque:
Oil filter element cover bolt:
15 Nm (1.5 m·kg)
Tightening torque:
Oil filter element drain screw:
7 Nm (0.7 m·kg)
Tightening torque:
Engine oil drain bolt:
43 Nm (4.3 m·kg)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-10
6
EC000066
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.
l
Make sure that no foreign mate-
rial enters the crankcase.
_11. 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. _12. Turn the engine off, and then
check the oil level and correct it if
necessary. Recommended engine oil:
See page 8-1.
Oil quantity:
Without oil filter element
replacement:
3.0 L
With oil filter element
replacement:
3.35 L
Total amount (dry engine):
4.2 L
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-11
6
EAU01755
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 3-11
for seat removal and installation
procedures.)
2. Remove panel A. (See page 6-5
for panel removal and installation
procedures.)
3. While lifting the leads as shown,
remove the air filter case cover by
removing the screws.4. Pull the air filter element out. 5. 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.
6. Insert the air filter element into the
air filter case.1. Air filter case cover
2. Screw (´ 4)
1. Air filter element
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-12
6
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.
_7. While lifting the leads as shown,
install the air filter case cover by
installing the screws.
8. Install the panel.
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. _
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-13
6
EAU00632
Adjusting the engine idling
speed The engine idling speed must be
checked and, if necessary, adjusted as
follows at the intervals specified in the
periodic maintenance and lubrication
chart.
1. Start the engine and warm it up
for several minutes at 1,000–
2,000 r/min while occasionally
revving it to 4,000–5,000 r/min.NOTE:_ The engine is warm when it quickly re-
sponds to the throttle. _
2. Check the engine idling speed
and, if necessary, adjust it to spec-
ification by turning the throttle stop
screw. To increase the engine
idling speed, turn the screw in di-
rection
a. To decrease the engine
idling speed, turn the screw in di-
rection
b.NOTE:_ If the specified idling speed cannot be
obtained as described above, have a
Yamaha dealer make the adjustment. _
EAU00635
Adjusting the throttle cable
free play The throttle cable free play should
measure 3–5 mm at the throttle grip.
Periodically check the throttle cable
free play and, if necessary, have a
Yamaha dealer adjust it.
1. Throttle stop screw
Engine idling speed:
1,000–1,100 r/min
a. Throttle cable free play
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