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PERIODIC MAINTENANCE AND ADJUSTMENT
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9
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).
TIP
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 check
the vehicle.
2. Check the spark plug for electrode
erosion and excessive carbon orother 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
1. Spark plug wrench
1
Specified spark plug:
PW50
NGK/BPR4HS
PW50Z NGK/BPR4HS
DENSO/W14FPL
1. Spark plug gap
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
1
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PERIODIC MAINTENANCE AND ADJUSTMENT
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EAU40892
Transmission oil
The transmission oil must be checked
for oil leakage before each ride. If any
leakage is found, have a Yamaha deal-
er check and repair the motorcycle. In
addition, the transmission oil must be
changed at the intervals specified in the
periodic maintenance and lubrication
chart.
1. Place the motorcycle on the cen-
terstand.
2. Place an oil pan under the trans-
mission to collect the used oil.
3. Remove the oil filler cap and drain
bolt to drain the oil from the trans-
mission.4. Install the transmission oil drain
bolt, and then tighten it to the spec-
ified torque.
5. Refill with the specified amount of
the recommended transmission
oil, and then install and tighten the
oil filler cap.
NOTICE
ECA10452
In order to prevent clutch slip-
page (since the transmission oil
also lubricates the clutch), do
not mix any chemical additives.
Do not use oils with a diesel
specification of “CD” or oils of a
higher quality than specified. In
addition, do not use oils labeled
“ENERGY CONSERVING II” or
higher.
Make sure that no foreign mate-
rial enters the transmission.
6. Start the engine, and then let it idle
for several minutes while checking
the transmission for oil leakage. If
oil is leaking, immediately turn the
engine off and check for the cause.
1. Transmission oil filler cap
1
1. Transmission oil drain bolt
Tightening torque:
Transmission oil drain bolt:
14 Nm (1.4 m·kgf, 10.1 ft·lbf)
Recommended transmission oil:
See page 9-1.
Oil change quantity:
0.30 L (0.32 US qt, 0.26 Imp.qt)
1
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PERIODIC MAINTENANCE AND ADJUSTMENT
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3. Insert the tailpipe into the muffler,
and then install and tighten the
screw.
TIP
Make sure to align the screw hole when
inserting the tailpipe.
EAU39930
Adjusting the carburetor
The carburetor is an important part of
the engine and requires 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 ser-
viced by the owner as part of routine
maintenance.
NOTICE
ECA10550
The carburetor has been set and ex-
tensively tested at the Yamaha fac-
tory. Changing these settings
without sufficient technical knowl-
edge may result in poor perfor-
mance of or damage to the engine.
EAU21362
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.
TIP
A diagnostic tachometer is needed to
make this adjustment.
1. Attach the tachometer to the spark
plug lead.
2. Start the engine and warm it up
for several minutes at 1000–2000
r/min while occasionally revving it
to 4000–5000 r/min.
TIP
The engine is warm when it quickly re-
sponds to the throttle.
3. 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 en-
1. Spark arrester
1
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PERIODIC MAINTENANCE AND ADJUSTMENT
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9
gine idling speed, turn the screw in
direction (b).
TIP
If the specified idling speed cannot be
obtained as described above, have a
Yamaha dealer make the adjustment.
EAU21382
Checking the throttle cable
free play
The throttle cable free play should mea-
sure 1.5–3.5 mm (0.06–0.14 in) at the
throttle grip. Periodically check the
throttle cable free play and, if neces-
sary, have a Yamaha dealer adjust it.
EAU40911
Tires
To maximize the performance, durabil-
ity, and safe operation of your motorcy-
cle, note the following points regarding
the specified tires.
Tire air pressure
The tire air pressure should be checked
and, if necessary, adjusted before each
ride.
WARNING
EWA14381
Operation of this vehicle with im-
proper tire pressure may cause se-
vere injury or death from loss of
control.
The tire air pressure must be
checked and adjusted on cold
tires (i.e., when the temperature
of the tires equals the ambient
temperature).
The tire air pressure must be ad-
justed in accordance with the
weight of the rider, the riding
speed, and the riding condi-
tions.
1. Throttle stop screw
Engine idling speed:
1650–1750 r/min
1(a) (b)
1. Throttle cable free play1
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PERIODIC MAINTENANCE AND ADJUSTMENT
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9 Rear
If the lining thickness of a brake shoe is
less than 1.5 mm (0.06 in), have a
Yamaha dealer replace the brake
shoes as a set.
TIP
Be sure to measure the brake lining at
the thinnest portion.
EAU41842
Checking and lubricating the
cables
The operation of all control cables and
the condition of the cables should be
checked before each ride, and the ca-
bles and cable ends should be lubricat-
ed if necessary. If a cable is damaged
or does not move smoothly, have a
Yamaha dealer check or replace it.
WARNING! Damage to the outer
housing of cables may result in in-
ternal rusting and cause interfer-
ence with cable movement. Replace
damaged cables as soon as possi-
ble to prevent unsafe condi-
tions.
[EWA10711]
EAU23111
Checking and lubricating the
throttle grip and cable
The operation of the throttle grip should
be checked before each ride. In addi-
tion, the cable should be lubricated at
the intervals specified in the periodic
maintenance chart.
Recommended lubricant:
Yamaha Chain and Cable Lube or
4-stroke engine oil
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PERIODIC MAINTENANCE AND ADJUSTMENT
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EAU23120
Adjusting the Autolube pump
The Autolube pump is a vital and so-
phisticated component of the engine,
which must be adjusted by a Yamaha
dealer at the intervals specified in the
periodic maintenance and lubrication
chart.
EAU43631
Lubricating the front and rear
brake levers
The pivoting points of the front and rear
brake levers must be lubricated at the
intervals specified in the periodic main-
tenance and lubrication chart.
EAU23192
Checking and lubricating the
centerstand
The operation of the centerstand
should be checked before each ride,
and the pivots and metal-to-metal con-
tact surfaces should be lubricated if
necessary.
WARNING
EWA11301
If the centerstand does not move up
and down smoothly, have a Yamaha
dealer check or repair it. Otherwise,
the centerstand could contact the
ground and distract the operator, re-
sulting in a possible loss of control.
Recommended lubricant:
Lithium-soap-based grease
Recommended lubricant:
Lithium-soap-based grease
Page 60 of 70
PERIODIC MAINTENANCE AND ADJUSTMENT
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EAU25972
Troubleshooting chart
Check the fuel level in
the fuel tank.1. Fuel
There is
enough fuel.
There is
no fuel.
Supply fuel.
Operate the kickstarter.2. Compression
There is compression.
There is
no compression.Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plug
and check the electrodes.3. Ignition
Wet
DryWipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the vehicle.The engine does not start.
Have a Yamaha dealer check the vehicle.
Open the throttle halfway and operate
the kickstarter.
Check the compression.
The engine does not start.
Check the compression.
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MOTORCYCLE CARE AND STORAGE
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3. Drain the carburetor float chamber
by loosening the drain bolt; this will
prevent fuel deposits from building
up. Pour the drained fuel into the
fuel tank.
4. Fill up the fuel tank and add fuel
stabilizer (if available) to prevent
the fuel tank from rusting and the
fuel from deteriorating.
5. Perform the following steps to pro-
tect the cylinder, piston rings, etc.
from corrosion.
a. Remove the spark plug cap
and spark plug.
b. Pour a teaspoonful of engine oil
into the spark plug bore.
c. Install the spark plug cap onto
the spark plug, and then place
the spark plug on the cylinder
head so that the electrodes are
grounded. (This will limit spark-
ing during the next step.)
d. Turn the engine over several
times with the starter. (This will
coat the cylinder wall with oil.)
e. Remove the spark plug cap
from the spark plug, and then
install the spark plug and thespark plug cap.
WARNING! To
prevent damage or injury
from sparking, make sure to
ground the spark plug elec-
trodes while turning the en-
gine over.
[EWA10951]
6. Lubricate all control cables and the
pivoting points of all levers and
pedals as well as of the center-
stand.
7. Check and, if necessary, correct
the tire air pressure, and then lift
the motorcycle so that both of its
wheels are off the ground. Alterna-
tively, turn the wheels a little every
month in order to prevent the tires
from becoming degraded in one
spot.
8. Cover the muffler outlet with a
plastic bag to prevent moisture
from entering it.
TIP
Make any necessary repairs before
storing the motorcycle.