2008 YAMAHA XT660Z engine

TABLE OF CONTENTS
SAFETY INFORMATION.....................1-1
Safe riding .........................................1-1
Protective apparel .............................1-2
Modifications .....................................1-2
Loading and accessories ..................1-2
Gasoline and exhaust gas ................1-4
DESCRIPTION .....................................2-1
Left view ............................................2-1
Right view .........................................2-2
Controls and instruments ..................2-3
INSTRUMENT AND CONTROL
FUNCTIONS ........................................3-1
Immobilizer system ...........................3-1
Main switch/steering lock ..................3-2
Indicator and warning lights ..............3-3
Multi-function display ........................3-5
Tachometer .......................................3-6
Tripmeter and tachometer modes .....3-6
Clock mode .......................................3-7
Fuel meter .........................................3-7
Self-diagnosis devices ......................3-7
Anti-theft alarm (optional) .................3-8
Handlebar switches ...........................3-9
Clutch lever .....................................3-10
Shift pedal .......................................3-10
Brake lever ......................................3-11
Brake pedal .....................................3-11 Fuel tank cap ..................................3-11
Fuel .................................................3-12
Fuel tank breather hose ..................3-13
Catalytic converter ..........................3-13
Seat .................................................3-14
Adjusting the front fork ....................3-15
Adjusting the shock absorber
assembly ..................................3-16
Sidestand ........................................3-17
Ignition circuit cut-off system ..........3-17
PRE-OPERATION CHECKS ...............4-1
Pre-operation check list ....................4-2
OPERATION AND IMPORTANT
RIDING POINTS ..................................5-1
Starting the engine............................5-1
Shifting ..............................................5-2
Tips for reducing fuel consumption ...5-3
Engine break-in .................................5-3
Parking ..............................................5-4
PERIODIC MAINTENANCE
AND MINOR REPAIR .........................6-1
Owner’s tool kit .................................6-1
Periodic maintenance and lubrication chart..........................6-2
Removing and installing the cowling and panels..................................6-8 Checking the spark plug ...................6-8
Engine oil and oil filter element.........6-9
Coolant ............................................6-12
Replacing the air filter element
and cleaning the check hose ..... 6-14
Checking the engine idling speed ...6-15
Checking the throttle cable free play ...................................6-16
Valve clearance ...............................6-16
Tires ................................................6-16
Spoke wheels..................................6-19
Adjusting the clutch lever free play ...................................6-20
Checking the front and rear brake pads ...............................6-21
Checking the brake fluid level .........6-22
Changing the brake fluid .................6-23
Drive chain slack .............................6-23
Cleaning and lubricating the drive chain ................................6-25
Checking and lubricating the cables .......................................6-25
Checking and lubricating the throttle grip and cable ..............6-26
Checking and lubricating the brake and clutch levers ............6-26
Lubricating the brake pedal ............6-27
Checking and lubricating the sidestand ..................................6-27

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10
SAFETY INFORMATION

• Always obey the speed limitand never travel faster than
warranted by road and traffic
conditions.
• Always signal before turning or changing lanes. Make sure that
other motorists can see you.
●The posture of the operator and
passenger is important for proper
control.
• The operator should keep bothhands on the handlebar and
both feet on the operator
footrests during operation to
maintain control of the motor-
cycle.
• The passenger should always hold onto the operator, the seat
strap or grab bar, if equipped,
with both hands and keep
both feet on the passenger
footrests.
• Never carry a passenger un- less he or she can firmly place
both feet on the passenger
footrests.
●Never ride under the influence of
alcohol or other drugs. Protective apparel
The majority of fatalities from motorcy-
cle accidents are the result of head in-
juries. The use of a safety helmet is the
single most critical factor in the pre-
vention or reduction of head injuries.
●Always wear an approved helmet.
●Wear a face shield or goggles.
Wind in your unprotected eyes
could contribute to an impairment
of vision that could delay seeing a
hazard.
●The use of a jacket, heavy boots,
trousers, gloves, etc., is effective
in preventing or reducing abra-
sions or lacerations.
●Never wear loose-fitting clothes,
otherwise they could catch on the
control levers, footrests, or
wheels and cause injury or an ac-
cident.
●Never touch the engine or ex-
haust system during or after oper-
ation. They become very hot and
can cause burns. Always wear
protective clothing that covers
your legs, ankles, and feet.
●Passengers should also observe
the precautions mentioned above.Modifications
Modifications made to this motorcycle
not approved by Yamaha, or the re-
moval of original equipment, may ren-
der the motorcycle unsafe for use and
may cause severe personal injury.
Modifications may also make your mo-
torcycle illegal to use.
Loading and accessories
Adding accessories or cargo to your
motorcycle can adversely affect stabili-
ty and handling if the weight distribution
of the motorcycle is changed. To avoid
the possibility of an accident, use ex-
treme caution when adding cargo or
accessories to your motorcycle. Use
extra care when riding a motorcycle
that has added cargo or accessories.
Here are some general guidelines to
follow if loading cargo or adding ac-
cessories to your motorcycle:
1-2

XT660Z 01-03 ING 10-03-2008 16:11 Pagina 9

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10
SAFETY INFORMATION

• Certain accessories can dis-place the operator from his or
her normal riding position. This
improper position limits the
freedom of movement of the
operator and may limit control
ability, therefore, such acces-
sories are not recommended.
●Use caution when adding electri-
cal accessories. If electrical ac-
cessories exceed the capacity of
the motorcycle's electrical sys-
tem, an electric failure could re-
sult, which could cause a danger-
ous loss of lights or engine power.
Gasoline and exhaust gas
●GASOLINE IS HIGHLY FLAMMA-
BLE:
• Always turn the engine off when refueling.
• Take care not to spill any gaso- line on the engine or exhaust
system when refueling.
• Never refuel while smoking or in the vicinity of an open flame.
●Never start the engine or let it run
for any length of time in a closed
area. The exhaust fumes are poi-
sonous and may cause loss of
consciousness and death within a
short time. Always operate your
motorcycle in an area that has ad-
equate ventilation.
●Always turn the engine off before
leaving the motorcycle unattend-
ed and remove the key from the
main switch. When parking the
motorcycle, note the following:
• The engine and exhaust sys-tem may be hot, therefore, park
the motorcycle in a place where
pedestrians or children are not
likely to touch these hot areas.
• Do not park the motorcycle on a slope or soft ground, other-
wise it may fall over.
• Do not park the motorcycle near a flammable source, (e.g.,
a kerosene heater, or near an
open flame), otherwise it could
catch fire.
●When transporting the motorcycle
in another vehicle, make sure that
it is kept upright and that the fuel
cock(s) are turned to “ON” or
“RES” (for vacuum type)/”OFF”
(for manual type). If the motorcy-
cle should lean over, gasoline
may leak out of the carburetor or
fuel tank.
●If you should swallow any gaso-
line, inhale a lot of gasoline vapor,
or allow gasoline to get into your
eyes, see your doctor immediate-
ly. If any gasoline spills on your
skin or clothing, immediately
wash the affected area with soap
and water and change your
clothes.
1-4

XT660Z 01-03 ING 10-03-2008 16:11 Pagina 11

DESCRIPTION
EAU10410Left view
1. Idle adjusting screw (page 6-15)
2. Owner’s tool kit (page 6-1)
3. Air filter element (page 6-14)
4. Fuse box (page 6-31)
5. Seat lock (page 3-14)6. Shock absorber assembly/spring preload adjusting ring (page 3-16)
7. Shift pedal (page 3-10)
8. Engine oil drain bolt (crankcase) (page 6-10)
9. Engine oil drain bolt (oil tank) (page 6-10)
2-1
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10. Grab bar
11. Main fuse (page 6-31)
12. Battery (page 6-30)
13. Rear brake fluid reservoir (page 6-22)14. Coolant reservoir (page 6-12) 15. Front brake fluid reservoir (page 6-22)
16. Coolant drain bolt (page 6-12)
17. Engine oil filter element (page 6-10)
18. Brake pedal (page 3-11)
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DESCRIPTION
EAU10420Right view
2-2

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DESCRIPTION
EAU10430
Controls and instruments
1. Clutch lever (page 3-10)
2. Left handlebar switches (page 3-9)
3. Multi-function meter unit and warning lights (page 3-3, 3-5)
4. Right handlebar switches (page 3-9)
5. Throttle grip (page 6-16)6. Brake lever (page 3-11)
7. Engine oil filler cap/dipstick (page 6-9)
8. Fuel tank cap (page 3-11)
9. Main switch and steering lock (page 3-2)
2-3
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INSTRUMENT AND CONTROL FUNCTIONS
3-2
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EAU10471
Main switch/steering lock
The main switch/steering lock controls
the ignition and lighting systems, and
is used to lock the steering.
NOTE:
Be sure to use the standard key (black
bow) for regular use of the vehicle. To
minimize the risk of losing the code re-
registering key (red bow), keep it in a
safe place and only use it for code re-
registering.

EAU10550
ON
All electrical circuits are supplied with
power, the meter lighting, taillight, li-
cense plate light and auxiliary lights
come on, and the engine can be start-
ed. The key cannot be removed.
NOTE:
The headlights comes on automatical-
ly when the engine is started and stay
on until the key is turned to “OFF”,
even if the engine stalls.
EAU10660
OFF
All electrical systems are off. The key
can be removed.
EAU10680
LOCK
The steering is locked, and all electri-
cal systems are off. The key can be re-
moved T
o lock the steering
1. Push
2. Turn
1. Turn the handlebars all the way to
the left.
2. Push the key in from the “OFF” position, and then turn it to
“LOCK” while still pushing it.
3. Remove the key.

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INSTRUMENT AND CONTROL FUNCTIONS
3-3
To unlock the steering
1. Push
2. Turn
Push the key in, and then turn it to
“OFF” while still pushing it.
EWA10060
WARNING0
Never turn the key to “OFF” or
“LOCK” while the vehicle is mov-
ing, otherwise the electrical sys-
tems will be switched off, which
may result in loss of control or an
accident. Make sure that the vehi-
cle is stopped before turning the
key to “OFF” or “LOCK”.

EAU10941
F(Parking)
The steering is locked, and the tail-
light, license plate light and auxiliary
lights are on. The hazard lights and
turn signal lights can be turned on, but
all other electrical systems are off. The
key can be removed.
The steering must be locked before
the key can be turned to “ F”.
ECA11020CAUTION:
Do not use the parking position for
an extended length of time, other-
wise the battery may discharge.
EAU11003
Indicator and warning lights
1. Immobilizer system indicator light “ ”
2. Neutral indicator light “ N”
3. Turn signal indicator light “ y”
4. High beam indicator light “ 1”
5. Engine trouble warning light “ U”
6. Coolant temperature warning light “ u”
EAUB1510
Turn signal indicator light “ y”
This indicator light flashes when the
turn signal switch is pushed to the left
or right.
The electrical circuit of the turn signal
indicator light can be checked by turn-
ing the key to "ON".
If the indicator light does not come on
for a few seconds, then go off, have a
Yamaha dealer check the electrical cir-
cuit.

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