2008 YAMAHA XT660X engine

TABLE OF CONTENTSSAFETY INFORMATION ..................1-1
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
Anti-theft alarm (optional) ...............3-7
Handlebar switches ........................3-7
Clutch lever .....................................3-9
Shift pedal .......................................3-9
Brake lever .....................................3-9
Brake pedal ..................................3-10
Fuel tank cap ................................3-10
Fuel ...............................................3-11
Catalytic converter ........................3-12
Seat ..............................................3-12
Storage compartment ...................3-13
Adjusting the shock absorber
assembly ...................................3-13
Sidestand ......................................3-14
Ignition circuit cut-off system ........3-15
PRE-OPERATION CHECKS..............4-1
Pre-operation check list ..................4-2OPERATION 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 cowlings
and panels .................................. 6-5
Checking the spark plug ................. 6-9
Engine oil and oil filter element .... 6-10
Coolant ......................................... 6-13
Replacing the air filter element and
cleaning the check hose ........... 6-16
Adjusting the engine idling
speed ........................................ 6-17
Checking the throttle cable free
play ........................................... 6-18
Tires ............................................. 6-18
Spoke wheels ............................... 6-21
Adjusting the clutch lever free
play ........................................... 6-21
Adjusting the rear brake light
switch ........................................ 6-22Checking the front and rear brake
pads .......................................... 6-22
Checking the brake fluid level ...... 6-23
Drive chain slack .......................... 6-24
Cleaning and lubricating the drive
chain ......................................... 6-26
Checking and lubricating the
cables ....................................... 6-27
Checking and lubricating the
throttle grip and cable ............... 6-27
Checking and lubricating the
brake and clutch levers ............ 6-27
Lubricating the brake pedal ......... 6-28
Checking and lubricating the
sidestand .................................. 6-28
Checking the front fork ................. 6-29
Checking the steering .................. 6-29
Checking the wheel bearings ....... 6-30
Battery ......................................... 6-30
Replacing the fuses ..................... 6-32
Replacing the headlight bulb ....... 6-33
Replacing a turn signal light bulb
or the tail/brake light bulb ......... 6-34
Replacing an auxiliary light bulb .. 6-35
Supporting the motorcycle ........... 6-35
Front wheel .................................. 6-36
Rear wheel ................................... 6-37
Troubleshooting ........................... 6-39
Troubleshooting charts ................ 6-40U5VKE1E0.book Page 1 Tuesday, July 18, 2006 1:00 PM

SAFETY INFORMATION
1-2
1 due to EXCESSIVE SPEED or un-
dercornering (insufficient lean an-
gle for the speed).
Always obey the speed limit and
never travel faster than warrant-
ed 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 both
hands on the handlebar and
both feet on the operator foot-
rests during operation to main-
tain control of the motorcycle.
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 unless
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 motor-
cycle accidents are the result of head
injuries. 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 abrasions
or lacerations.


Never wear loose-fitting clothes,
otherwise they could catch on the
control levers, footrests, or wheels
and cause injury or an accident.


Never touch the engine or exhaust
system during or after operation.
They become very hot and can
cause burns. Always wear protec-
tive 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
motorcycle 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 acces-
sories to your motorcycle:
Loading
The total weight of the operator, pas-
senger, accessories and cargo must
not exceed the maximum load limit.
Maximum load:
186 kg (410 lb)
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SAFETY INFORMATION
1-3
1When loading within this weight limit,
keep the following in mind:


Cargo and accessory weight
should be kept as low and close to
the motorcycle as possible. Make
sure to distribute the weight as
evenly as possible on both sides of
the motorcycle to minimize imbal-
ance or instability.


Shifting weights can create a sud-
den imbalance. Make sure that ac-
cessories and cargo are securely
attached to the motorcycle before
riding. Check accessory mounts
and cargo restraints frequently.


Never attach any large or heavy
items to the handlebar, front fork,
or front fender. These items, in-
cluding such cargo as sleeping
bags, duffel bags, or tents, can
create unstable handling or a slow
steering response.
Accessories
Genuine Yamaha accessories have
been specifically designed for use on
this motorcycle. Since Yamaha cannot
test all other accessories that may be
available, you must personally be re-
sponsible for the proper selection, in-stallation and use of non-Yamaha
accessories. Use extreme caution
when selecting and installing any ac-
cessories.
Keep the following guidelines in mind,
as well as those provided under “Load-
ing” when mounting accessories.


Never install accessories or carry
cargo that would impair the perfor-
mance of your motorcycle. Care-
fully inspect the accessory before
using it to make sure that it does
not in any way reduce ground
clearance or cornering clearance,
limit suspension travel, steering
travel or control operation, or ob-
scure lights or reflectors.
Accessories fitted to the handle-
bar or the front fork area can
create instability due to improper
weight distribution or aerody-
namic changes. If accessories
are added to the handlebar or
front fork area, they must be as
lightweight as possible and
should be kept to a minimum.
Bulky or large accessories may
seriously affect the stability of
the motorcycle due to aerody-namic effects. Wind may at-
tempt to lift the motorcycle, or
the motorcycle may become un-
stable in cross winds. These ac-
cessories may also cause
instability when passing or being
passed by large vehicles.
Certain accessories can dis-
place the operator from his or
her normal riding position. This
improper position limits the free-
dom of movement of the opera-
tor and may limit control ability,
therefore, such accessories are
not recommended.


Use caution when adding electri-
cal accessories. If electrical acces-
sories exceed the capacity of the
motorcycle’s electrical system, an
electric failure could result, which
could cause a dangerous loss of
lights or engine power.
Gasoline and exhaust gas


GASOLINE IS HIGHLY FLAMMA-
BLE:
Always turn the engine off when
refueling.
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SAFETY INFORMATION
1-4
1 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 unattended
and remove the key from the main
switch. When parking the motor-
cycle, note the following:
The engine and exhaust system
may be hot, therefore, park the
motorcycle in a place where pe-
destrians or children are not like-
ly to touch these hot areas.
Do not park the motorcycle on a
slope or soft ground, otherwise it
may fall over.Do not park the motorcycle near
a flammable source (e.g., a ker-
osene 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 motorcycle
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 immediately.
If any gasoline spills on your skin
or clothing, immediately wash the
affected area with soap and water
and change your clothes.
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DESCRIPTION
2-1
2
EAU10410
Left view1. Windshield
2. Idle adjusting screw (page 6-17)
3. Main fuse (page 6-32)
4. Battery (page 6-30)
5. Fuse box 1 (page 6-32)
6. Fuse box 2 (page 6-32)
7. Storage compartment (page 3-13)
8. Grab bar9. Seat lock (page 3-12 )
10.Shift pedal (page 3-9)
11.Engine oil drain bolt (crankcase) (page 6-10)U5VKE1E0.book Page 1 Tuesday, July 18, 2006 1:00 PM

DESCRIPTION
2-2
2
EAU10420
Right view1. Owner’s tool kit (page 6-1)
2. Air filter element (page 6-16)
3. Shock absorber assembly spring preload adjusting ring (page 3-13)
4. Rear brake fluid reservoir (page 6-23)
5. Front brake fluid reservoir (page 6-23)
6. Engine oil filler cap (page 6-10)
7. Engine oil drain bolt (oil tank) (page 6-10)
8. Coolant reservoir (page 6-13)9. Engine oil filter element (page 6-10)
10.Coolant drain bolt (page 6-14)
11.Brake pedal (page 3-10)
U5VKE1E0.book Page 2 Tuesday, July 18, 2006 1:00 PM

INSTRUMENT AND CONTROL FUNCTIONS
3-2
3
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.
EAU10570
ON
All electrical circuits are supplied with
power; the meter lighting, taillight and
auxiliary light come on, and the engine
can be started. The key cannot be re-
moved.NOTE:The headlight comes on automatically
when the engine is started and stays onuntil the key is turned to “OFF”.
EAU10660
OFF
All electrical systems are off. The key
can be removed.
EAU10680
LOCK
The steering is locked, and all electrical
systems are off. The key can be re-
moved.To lock the steering
1. Turn the handlebars all the way to
the left.
2. Push the key in from the “OFF” po-
sition, and then turn it to “LOCK”
while still pushing it.
3. Remove the key.1. Push.
2. Turn.
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INSTRUMENT AND CONTROL FUNCTIONS
3-3
3To unlock the steering
Push the key in, and then turn it to
“OFF” while still pushing it.
WARNING
EWA10060
Never turn the key to “OFF” or
“LOCK” while the vehicle is moving,
otherwise the electrical systems will
be switched off, which may result in
loss of control or an accident. Make
sure that the vehicle is stopped be-
fore turning the key to “OFF” or“LOCK”.
EAU33001
(Parking)
The steering is locked, and the taillight
and auxiliary light are on. The hazard
lights and turn signal lights can be
turned on, but all other electrical sys-
tems are off. The key can be removed.
The steering must be locked before the
key can be turned to “”.
CAUTION:
ECA11020
Do not use the parking position for
an extended length of time, other-wise the battery may discharge.
EAU11003
Indicator and warning lights
EAU11020
Turn signal indicator light “”
This indicator light flashes when the
turn signal switch is pushed to the left or
right.
EAU11060
Neutral indicator light “”
This indicator light comes on when the
transmission is in the neutral position.
1. Push.
2. Turn.
1. Engine trouble warning light “”
2. Turn signal indicator light “”
3. Fuel level warning light “”
4. High beam indicator light “”
5. Neutral indicator light “”
6. Coolant temperature warning light “”
7. Immobilizer system indicator light “”
U5VKE1E0.book Page 3 Tuesday, July 18, 2006 1:00 PM