engine YAMAHA YZF-R6 2002 Owner's Guide

PERIODIC MAINTENANCE AND MINOR REPAIR
6-17
617. Remove the radiator cap to check
the coolant level in the radiator. If
necessary, add sufficient coolant
until it reaches the top of the radia-
tor, and then install the radiator
cap.
18. Start the engine, and then check
the vehicle for coolant leakage. If
coolant is leaking, have a Yamaha
dealer check the cooling system.
19. Install the panel and the cowlings.
EAU04256*
Checking the air filter element The air filter element should be
checked at the intervals specified in the
periodic maintenance and lubrication
chart. Check the air filter element more
frequently if you are riding in unusually
wet or dusty areas.
1. Remove the rider seat. (See
page 3-13 for rider seat removal
and installation procedures.)
2. Remove the fuel tank bolts and
slightly lift the fuel tank.3. Turn the fuel cock lever to “OFF”,
and then disconnect the hoses
and the fuel sender coupler.
NOTE:_ Before removing the hoses, mark them
to ensure that they will be reinstalled in
their correct positions. _
1. Bolt (× 2)
1. Fuel cock
2. Hose (× 2)
3. Fuel sender coupler
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-19
68. Insert the element into the air filter
case.
EC000082*
CAUTION:_

Make sure that the air filter ele-
ment is properly seated in the
air filter case.


The engine should never be op-
erated without the air filter ele-
ment installed, otherwise the
pistons and/or cylinders may
become excessively worn.
_9. Install the air filter case cover by
installing the screws.
10. Connect the fuel sender coupler
and the hoses, turn the fuel cock
lever to “ON”, place the fuel tank in
the original position, and then in-
stall the bolts.
EW000131
WARNING
_ Make sure that the fuel hoses and
vacuum hose are properly connect-
ed and routed, and not pinched. Re-
place any damaged hoses. _11. Install the rider seat.
EAU01335
Air intake duct Check that the screen of the intake
duct is not blocked. Clean the screen if
necessary.1. Air intake duct
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-20
6
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. @
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 rev-
ving 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
direction
b.NOTE:@ If the specified idling speed cannot be
obtained as described above, have a
Yamaha dealer make the adjustment. @ 1. Throttle stop screwEngine idling speed:
1,250–1,350 r/min
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-21
6
EAU00635
Adjusting the throttle cable
free play The throttle cable free play should
measure 6–8 mm at the throttle grip.
Periodically check the throttle cable
free play and, if necessary, have a
Yamaha dealer adjust it.
EAU00637
Adjusting the valve clearance The valve clearance changes with use,
resulting in improper air-fuel mixture
and/or engine noise. To prevent this
from occurring, the valve clearance
must be adjusted by a Yamaha dealer
at the intervals specified in the periodic
maintenance and lubrication chart.
EAU00658
Tires To maximize the performance, durabil-
ity, and safe operation of your motor-
cycle, 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.
EW000082
WARNING
@

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
adjusted in accordance with the
riding speed and with the total
weight of rider, passenger, car-
go, and accessories approved
for this model.
@
a. Throttle cable free playU5MTE1.book Page 21 Monday, August 6, 2001 6:10 PM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-30
6 3. Move the rear wheel by pushing
the motorcycle to locate the tight-
est portion of the drive chain, and
then measure the drive chain
slack as shown.
4. If the drive chain slack is incorrect,
adjust it as follows.
EAU03608
To adjust the drive chain slack
1. Loosen the axle nut and the lock-
nut on each side of the swingarm.
2. To tighten the drive chain, turn the
adjusting bolt on each side of the
swingarm in direction
a. To loos-
en the drive chain, turn the adjust-
ing bolt on each side of the
swingarm in direction
b, and then
push the rear wheel forward.
NOTE:_ Using the alignment marks on each
side of the swingarm, make sure that
both chain pullers are in the same posi-
tion for proper wheel alignment. _
EC000096
CAUTION:_ Improper drive chain slack will over-
load the engine as well as other vital
parts of the motorcycle and can lead
to chain slippage or breakage. To
prevent this from occurring, keep
the drive chain slack within the
specified limits. _3. Tighten the locknuts, and then
tighten the axle nut to the specified
torque.
a. Drive chain slack
Drive chain slack:
40–50 mm
1. Axle nut
2. Drive chain slack adjusting bolt
3. Locknut
4. Alignment marks
Tightening torque:
Axle nut:
150 Nm (15.0 m·kgf)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-31
6
EAU03006
Lubricating the drive chain The drive chain must be cleaned and
lubricated at the intervals specified in
the periodic maintenance and lubrica-
tion chart, otherwise it will quickly wear
out, especially when riding in dusty or
wet areas. Service the drive chain as
follows.
EC000097
CAUTION:@ The drive chain must be lubricated
after washing the motorcycle or
riding in the rain. @1. Clean the drive chain with kero-
sene and a small soft brush.
ECA00053
CAUTION:@ To prevent damaging the O-rings,
do not clean the drive chain with
steam cleaners, high-pressure
washers or inappropriate solvents. @2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive
chain with a special O-ring chain
lubricant.
ECA00052
CAUTION:@ Do not use engine oil or any other
lubricants for the drive chain, as
they may contain substances that
could damage the O-rings. @
EAU02962
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.
EW000112
WARNING
@ Damage to the outer sheath may in-
terfere with proper cable operation
and will cause the inner cable to
rust. Replace a damaged cable as
soon as possible to prevent unsafe
conditions. @
Recommended lubricant:
Engine oil
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-34
6 To check the operation
1. Place the motorcycle on a level
surface and hold it in an upright
position.
2. While applying the front brake,
push down hard on the handle-
bars several times to check if the
front fork compresses and re-
bounds smoothly.
EC000098
CAUTION:@ If any damage is found or the front
fork does not operate smoothly,
have a Yamaha dealer check or re-
pair it. @
EAU00794
Checking the steering Worn or loose steering bearings may
cause danger. Therefore, the operation
of the steering must be checked as fol-
lows at the intervals specified in the pe-
riodic maintenance and lubrication
chart.
1. Place a stand under the engine to
raise the front wheel off the
ground.
EW000115
WARNING
@ Securely support the motorcycle so
that there is no danger of it falling
over. @
2. Hold the lower ends of the front
fork legs and try to move them for-
ward and backward. If any free
play can be felt, have a Yamaha
dealer check or repair the
steering.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-39
6
EAU03730
Tail/brake light This motorcycle is equipped with an
LED type of tail/brake light.
If the tail/brake light does not come on,
have a Yamaha dealer check it.
EAU03497
Replacing a turn signal light
bulb 1. Remove the turn signal light lens
by removing the screw.
2. Remove the defective bulb by
pushing it in and turning it
counterclockwise.
3. Insert a new bulb into the socket,
push it in, and then turn it clock-
wise until it stops.
4. Install the lens by installing the
screw.
ECA00065
CAUTION:@ Do not overtighten the screw, other-
wise the lens may break. @
EAU01579
Supporting the motorcycle Since this model is not equipped with a
centerstand, follow these precautions
when removing the front and rear
wheel or performing other mainte-
nance requiring the motorcycle to
stand upright. Check that the motor-
cycle is in a stable and level position
before starting any maintenance. A
strong wooden box can be placed un-
der the engine for added stability.
To service the front wheel
1. Stabilize the rear of the motorcycle
by using a motorcycle stand or, if
an additional motorcycle stand is
not available, by placing a jack un-
der the frame in front of the rear
wheel.
2. Raise the front wheel off the
ground by using a motorcycle
stand.
1. Screw
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-44
6
EAU02990
Troubleshooting charts Starting problems or poor engine performance
EW000125
WARNING
@ Keep away open flames and do not smoke while checking or working on the fuel system. @
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plugs
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gaps, or replace the spark plugs.
Have a Yamaha dealer check the vehicle.
The engine does not start.
Have a Yamaha dealer
check the vehicle.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.DryWet
The engine does not start.
Check the battery.Open the throttle halfway and operate
the electric starter.
The battery is good.Check the battery lead connections,
and charge the battery if necessary.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-45
6Engine overheating
EW000070
WARNING
@

Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be
blown out under pressure, which could cause serious injury. Be sure to wait until the engine has cooled.


After removing the radiator cap retaining bolt, place a thick rag, like a towel, over the radiator cap, and then
slowly rotate the cap counterclockwise to the detent to allow any residual pressure to escape. When the hiss-
ing sound has stopped, press down on the cap while turning it counterclockwise, and then remove the cap.
@aNOTE:@ If coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended coolant
as soon as possible. @
Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.Add coolant. (See NOTE.)
Start the engine. If the engine overheats again,
have a
Yamaha dealer check
and repair the cooling system.
There is
leakage.
There is
no leakage.
U5MTE1.book Page 45 Monday, August 6, 2001 6:10 PM