2008 YAMAHA XT660Z transmission

INSTRUMENT AND CONTROL FUNCTIONS
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EAUB1520
Neutral indicator light “ N”
This indicator light comes on when the
transmission is in the neutral position.
The electrical circuit of the neutral indi-
cator light can be checked by turning
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.
EAUB1530
High beam indicator light “ 1”
This indicator light comes on when the
high beam of the headlight is switched
on. The electrical circuit of the high
beam indicator light can be checked
by turning 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.
EAU11440
Coolant temperature warning
light “u ”
This warning light comes on when the
engine overheats. When this occurs,
stop the engine immediately and allow
the engine to cool. The electrical circuit of the warning
light can be checked by turning the
key to “ON”.
If the warning light does not come on
for a few seconds, then go off, have a
Yamaha dealer check the electrical cir-
cuit.
ECA10020
CAUTION:
Do not operate the engine if it is
overheated.
EAU11530
Engine trouble warning light “ U”
This warning light comes on or flashes
when an electrical circuit monitoring
the engine is defective. When this oc-
curs, have a Yamaha dealer check the
self-diagnosis system. (See page 3-7
for an explanation of the self-diagnosis
device.)
The electrical circuit of the warning
light can be checked by turning the
key to “ON”. If the warning light does
not come on for a few seconds, then
go off, have a Yamaha dealer check
the electrical circuit.
EAU26873
Immobilizer system indicator
light “ ”
The electrical circuit of the indicator
light can be checked by turning the
key to “ON”.
If the inidcator light does not come on
for a few seconds, then go off, have a
Yamaha dealer check the electrical cir-
cuit.
When the key is turned to “OFF” and
30 seconds have passed, the indicator
light will start flashing indicating the
immobilizer system is enabled. After
24 hours have passed, the indicator
light will stop flashing, however the im-
mobilizer system is still enabled.
This model is also equipped with a
self-diagnosis device for the immobi-
lizer system. (See page 3-7 for an ex-
planation of the self-diagnosis device.)

XT660Z 01-03 ING 10-03-2008 16:11 Pagina 3-4

INSTRUMENT AND CONTROL FUNCTIONS
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EAU12733
Hazard switch “r”
With the key in the “ON” or Fposition,
use this switch to turn on the hazard
lights (simultaneous flashing of all turn
signal lights).
The hazard lights are used in case of
an emergency or to warn other drivers
when your vehicle is stopped where it
might be a traffic hazard.
ECA10061CAUTION:
Do not use the hazard lights for an
extended length of time with the
engine not running, otherwise the
battery may discharge.
EAU12820
Clutch lever
1. Clutch lever
The clutch lever is located at the left
handlebar grip. To disengage the
clutch, pull the lever toward the han-
dlebar grip. To engage the clutch, re-
lease the lever. The lever should be
pulled rapidly and released slowly for
smooth clutch operation.
The clutch lever is equipped with a
clutch switch, which is part of the igni-
tion circuit cut-off system. (See page
3-17).

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EAU12870
Shift pedal
1. Shift pedal
The shift pedal is located on the left
side of the engine and is used in com-
bination with the clutch lever when
shifting the gears of the 5-speed con-
stant-mesh transmission equipped on
this motorcycle.

XT660Z 01-03 ING 10-03-2008 16:11 Pagina 3-10

EWA10240
WARNING0
The vehicle must not be ridden
with the sidestand down, or if the
sidestand cannot be properly
moved up (or does not stay up),
otherwise the sidestand could con-
tact the ground and distract the
operator, resulting in a possible
loss of control. Yamaha’s ignition
circuit cut-off system has been de-
signed to assist the operator in ful-
filling the responsibility of raising
the sidestand before starting off.
Therefore, check this system regu-
larly as described below and have
a Yamaha dealer repair it if it does
not function properly.

EAU15301
Sidestand
1. Sidestand
The sidestand is located on the left
side of the frame. Raise the sidestand
or lower it with your foot while holding
the motorcycle upright.
NOTE:
The built-in sidestand switch is part of
the ignition circuit cut-off system,
which cuts the ignition in certain situa-
tions. (See further down for an expla-
nation of the ignition circuit cut-off sys-
tem.)

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INSTRUMENT AND CONTROL FUNCTIONS
3-17
EAU15312
Ignition circuit cut-off
system
The ignition circuit cut-off system
(comprising the sidestand switch,
clutch switch and neutral switch) has
the following functions.
●It prevents starting when the
transmission is in gear and the
sidestand is up, but the clutch
lever is not pulled.
●It prevents starting when the
transmission is in gear and the
clutch lever is pulled, but the side-
stand is still down.
●It cuts the running engine when
the transmission is in gear and
the sidestand is moved down.
Periodically check the operation of the
ignition circuit cut-off system accord-
ing to the following procedure.
EWA10250
WARNING0
If a malfunction is noted, have a
Yamaha dealer check the system
before riding.

XT660Z 01-03 ING 10-03-2008 16:11 Pagina 3-17

INSTRUMENT AND CONTROL FUNCTIONS
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With the engine turned off:
1. Move the sidestand down.
2. Make sure that the engine stop switch is turned on.
3. Turn the key on.
4. Shift the transmission into the neutral position.
5. Push the start switch.
Does the engine start?
With the engine still running:
6. Move the sidestand up.
7. Keep the clutch lever pulled.
8. Shift the transmission into gear.
9. Move the sidestand down.
Does the engine stall?
NOTE:
This check is most reliable if performed with a
warmed-up engine.
The neutral switch may be defective.
The motorcycle should not be ridden until checked by a
Yamaha dealer.
The sidestand switch may be defective.
The motorcycle should not be ridden until checked by a
Yamaha dealer.
The clutch switch may be defective.
The motorcycle should not be ridden until checked by a
Yamaha dealer.
After the engine has stalled:
10. Move the sidestand up.
11. Keep the clutch lever pulled.
12. Push the start switch.
Does the engine start?
The system is OK. The motorcycle can be ridden.
YES NO
NO
YES
NO
YES

XT660Z 01-03 ING 10-03-2008 16:11 Pagina 3-18

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OPERATION AND IMPORTANT RIDING POINTS
EAU15950
EWA10270
WARNING0
●Become thoroughly familiar
with all operating controls and
their functions before riding.
Consult a Yamaha dealer re-
garding any control or function
that you do not thoroughly un-
derstand.
●Never start the engine or oper-
ate it in a closed area for any
length of time. Exhaust fumes
are poisonous, and inhaling
them can cause loss of con-
sciousness and death within a
short time. Always make sure
that there is adequate ventila-
tion.
●Before starting out, make sure
that the sidestand is up. If the
sidestand is not raised com-
pletely, it could contact the
ground and distract the opera-
tor, resulting in a possible loss
of control.

EAUB1570
Starting the engine
In order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:
●The transmission is in the neutral
position.
●The transmission is in gear with
the clutch lever pulled and the
sidestand up.
EWA10290
WARNING0
●Before starting the engine,
check the function of the igni-
tion circuit cut-off system ac-
cording to the procedure de-
scribed on page 3-18.
●Never ride with the sidestand
down.
1. Turn the key to “ON” and make sure that the engine stop switch is
set to “
I”.

ECAB0070CAUTION:
The following warning lights and in-
dicator lights should come on for a
few seconds, then go off.
●Neutral indicator light
●Turn signal indicator light
●High beam indicator light
●Engine trouble warning light
●Coolant temperature warning
light
●Immobilizer system indicator
light
If a warning or indicator light does
not go off, see page 3-3 for the cor-
responding warning and indicator
light circuit check.
2. Shift the transmission into the neutral position.
NOTE:
When the transmission is in the neu-
tral position, the neutral indicator light
should be on, otherwise have a Yama-
ha dealer check the electrical circuit.
5-1

XT660Z 04-06 ING 11-03-2008 8:30 Pagina 5-1

OPERATION AND IMPORTANT RIDING POINTS
3. Start the engine by pushing thestart switch.
NOTE:
If the engine fails to start, release the
start switch, wait a few seconds, and
then try again. Each starting attempt
should be as short as possible to pre-
serve the battery. Do not crank the en-
gine more than 10 seconds on any one
attempt.
ECA11040CAUTION:
For maximum engine life, never ac-
celerate hard when the engine is
cold!
NOTE:
The engine is warm when it quickly re-
sponds to the throttle.
EAU16671
Shifting
1. Shift pedal
N. Neutral position
Shifting gears lets you control the
amount of engine power available for
starting off, accelerating, climbing
hills, etc.
The gear positions are shown in the il-
lustration.
NOTE:
To shift the transmission into the neu-
tral position, press the shift pedal down
repeatedly until it reaches the end of its
travel, and then slightly raise it.

ECA10260CAUTION:
●Even with the transmission in
the neutral position, do not
coast for long periods of time
with the engine off, and do not
tow the motorcycle for long
distances. The transmission is
properly lubricated only when
the engine is running. Inade-
quate lubrication may damage
the transmission.
●Always use the clutch while
changing gears to avoid dam-
aging the engine, transmission,
and drive train, which are not
designed to withstand the
shock of forced shifting.
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XT660Z 04-06 ING 11-03-2008 8:30 Pagina 5-2

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PERIODIC MAINTENANCE AND MINOR REPAIR
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EAU22730
Changing the brake fluid
Have a Yamaha dealer change the
brake fluid at the intervals specified in
the NOTE after the periodic mainte-
nance and lubrication chart. In addi-
tion, have the oil seals of the master
cylinders and calipers as well as the
brake hoses replaced at the intervals
listed below or whenever they are
damaged or leaking.
●Oil seals: Replace every two
years.
●Brake hoses: Replace every four
years.
EAU22760
Drive chain slack
The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU22783
To check the drive chain slack
1. Drive chain slack
1. Place the motorcycle on the side-stand.
NOTE:
When checking and adjusting the dri-
ve chain slack, there should be no
weight on the motorcycle.
2. Shift the transmission into theneutral position.
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 incor- rect, adjust it as follows.
NOTE:
When checking the drive chain slack,
the chain tensioner should not be
touching the drive chain.
Drive chain slack:50.0-60.0 mm (1.96-2.36 in)
XT660Z 04-06 ING 11-03-2008 10:41 Pagina 6-23

SPECIFICATIONS
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Engine oil:Type: SAE10W30 or SAE10W40 or SAE15W40
or SAE20W40 or SAE20W50
Recommended engine oil grade: API service SE, SF, SG type or higher
Engine oil quantity: Without oil filter element replacement:2.50 L (2.64 US qt) (2.19 Imp.qt)
With oil filter element replacement: 2.60 L (2.73 US qt) (2.26 Imp.qt)
Total amount (dry engine): 2.90 L (3.07 US qt) (2.55 Imp.qt)
Cooling system:Radiator capacity (including all routes): 1.2 L (1.26 US qt) (1.05 Imp.qt) (Radiator) +
0.5 L (0.52 US qt) (0.44 Imp.qt)
(Coolant reservoir)
Coolant reservoir capacity (up to the
maximum level mark): 0.50 L (0.52 US qt) (0.44 Imp.qt)
From low to full level: 0.30 L (0.32 US qt) (0.26 Imp.qt)
Air filter:Air filter element:Paper
Fuel:Recommended fuel:Premium unleaded gasoline only
Fuel tank capacity: 23.0 L (6.07 US gal) (5.06 Imp.gal)
Fuel reserve amount: 6.7 L (1.76 US gal) (1.46 Imp.gal)
Fuel injection:Manufacturer:DENSO
Model: 297500-0390
Spark plug:Manufacturer/model:NGK/CR7EGap:0.7-0.8 mm (0.028-0.032 in)
Clutch:Clutch type:Wet, multiple-disc
Transmission:Primary reduction system:Spur gear
Primary reduction ratio: 75/36 (2.083)
Secondary reduction system: Chain drive
Secondary reduction ratio: 45/15 (3.00)
Transmission type: Constant mesh 5-speed
Dimensions:Overall length:2246 mm (88.42 in)
Overall width: 864 mm (34.01 in)
Overall height: 1477 mm (58.14 in)
Seat height: 896 mm (35.27 in)
Wheelbase: 1500 mm (59.05 in)
Ground clearance: 260 mm (10.23 in)
Minimum turning radius: 1958 mm (77.08 in)
Basic weight:With oil and fuel:208.5 kg (459 lb)
Engine:Engine type:Liquid cooled 4-stroke, SOHC
Cylinder arrangement: Forward-inclined single cylinder
Displacement: 660.0 cm
3(40.27 cu.in)
Bore x stroke: 100.0 x 84.0 mm (3.94 x 3.31 in)
Compression ratio: 10.00 : 1
Starting system: Electric starter
Lubrication system: Dry sump
-20 -10 0 10 20 30 40 50 °C
SAE 10W-30
SAE 10W-40
SAE 20W-40
SAE 20W-50
SAE 15W-40

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