Page 32 of 98

INSTRUMENT AND CONTROL FUNCTIONS
3-15
3
EAUB1302
Fuel tank breather/overflow
hoseBefore operating the motorcycle:
Check the fuel tank breather/over-
flow hose connection.
Check the fuel tank breather/over-
flow hose for cracks or damage,
and replace it if necessary.
Make sure that the end of the fuel
tank breather/overflow hose is not
blocked, and clean it if necessary.
Make sure that the fuel tank
breather/overflow hose is routed
through the clamp.
EAU13434
Catalytic converterThis model is equipped with a catalytic
converter in the exhaust system.
WARNING
EWA10863
The exhaust system is hot after op-
eration. To prevent a fire hazard or
burns:
Do not park the vehicle near
possible fire hazards such as
grass or other materials that
easily burn.
Park the vehicle in a place
where pedestrians or children
are not likely to touch the hot
exhaust system.
Make sure that the exhaust sys-
tem has cooled down before
doing any maintenance work.
Do not allow the engine to idle
more than a few minutes. Long
idling can cause a build-up of
heat.
NOTICE
ECA10702
Use only unleaded gasoline. The use
of leaded gasoline will cause unre-
pairable damage to the catalytic
converter.
1. Fuel tank breather/overflow hose
2. Hose clampU2BDE1E0.book Page 15 Tuesday, December 16, 2014 5:38 PM
Page 38 of 98

FOR YOUR SAFETY – PRE-OPERATION CHECKS
4-1
4
EAU15599
Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always follow the inspection
and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWA11152
Failure to inspect or maintain the vehicle properly increases the possibility of an accident or equipment damage.
Do not operate the vehicle if you find any problem. If a problem cannot be corrected by the procedures provided in
this manual, have the vehicle inspected by a Yamaha dealer.Before using this vehicle, check the following points:
ITEM CHECKS PAGE
Fuel• Check fuel level in fuel tank.
• Refuel if necessary.
• Check fuel line for leakage.
• Check fuel tank breather hose and overflow hose for obstructions, cracks or
damage, and check hose connections.3-13, 3-15
Engine oil• Check oil level in oil tank.
• If necessary, add recommended oil to specified level.
• Check vehicle for oil leakage.6-10
Coolant• Check coolant level in reservoir.
• If necessary, add recommended coolant to specified level.
• Check cooling system for leakage.6-13
Front brake• Check operation.
• If soft or spongy, have Yamaha dealer bleed hydraulic system.
• Check lever free play.
• Adjust if necessary.
• Check brake pads for wear.
• Replace if necessary.
• Check fluid level in reservoir.
• If necessary, add specified brake fluid to specified level.
• Check hydraulic system for leakage.6-21, 6-21
U2BDE1E0.book Page 1 Tuesday, December 16, 2014 5:38 PM
Page 43 of 98

OPERATION AND IMPORTANT RIDING POINTS
5-3
5
NOTICE
ECA10261
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 dis-
tances. 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.
EAU16811
Tips for reducing fuel con-
sumptionFuel consumption depends largely on
your riding style. Consider the follow-
ing tips to reduce fuel consumption:
Shift up swiftly, and avoid high en-
gine speeds during acceleration.
Do not rev the engine while shift-
ing down, and avoid high engine
speeds with no load on the en-
gine.
Turn the engine off instead of let-
ting it idle for an extended length
of time (e.g., in traffic jams, at traf-
fic lights or at railroad crossings).
EAU16842
Engine break-inThere is never a more important period
in the life of your engine than the period
between 0 and 1600 km (1000 mi). For
this reason, you should read the fol-
lowing material carefully.
Since the engine is brand new, do not
put an excessive load on it for the first
1600 km (1000 mi). The various parts in
the engine wear and polish themselves
to the correct operating clearances.
During this period, prolonged full-throt-
tle operation or any condition that
might result in engine overheating
must be avoided.
EAU17103
0–1000 km (0–600 mi)
Avoid prolonged operation above 4500
r/min. NOTICE: After 1000 km (600
mi) of operation, the engine oil must
be changed, and the oil filter ele-
ment replaced.
[ECA11152]
1000–1600 km (600–1000 mi)
Avoid prolonged operation above 6000
r/min.
U2BDE1E0.book Page 3 Tuesday, December 16, 2014 5:38 PM
Page 44 of 98
OPERATION AND IMPORTANT RIDING POINTS
5-4
51600 km (1000 mi) and beyond
The vehicle can now be operated nor-
mally.
NOTICE
ECA10311
Keep the engine speed out of
the tachometer red zone.
If any engine trouble should oc-
cur during the engine break-in
period, immediately have a
Yamaha dealer check the vehi-
cle.
EAU17214
ParkingWhen parking, stop the engine, and
then remove the key from the main
switch.
WARNING
EWA10312
Since the engine and exhaust
system can become very hot,
park in a place where pedestri-
ans or children are not likely to
touch them and be burned.
Do not park on a slope or on soft
ground, otherwise the vehicle
may overturn, increasing the
risk of a fuel leak and fire.
Do not park near grass or other
flammable materials which
might catch fire.
U2BDE1E0.book Page 4 Tuesday, December 16, 2014 5:38 PM
Page 47 of 98

PERIODIC MAINTENANCE AND ADJUSTMENT
6-3
6
EAU46862
TIPThe annual checks must be performed every year, except if a kilometer-based maintenance, or for the UK, a
mileage-based maintenance, is performed instead.
From 50000 km (30000 mi), repeat the maintenance intervals starting from 10000 km (6000 mi).
Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools, data and tech-
nical skills.
EAU46911
Periodic maintenance chart for the emission control systemNO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING
ANNUAL
CHECK 1000 km
(600 mi)10000 km
(6000 mi)20000 km
(12000 mi)30000 km
(18000 mi)40000 km
(24000 mi)
1*Fuel line• Check fuel hoses for cracks or
damage.√√√√√
2 Spark plug• Check condition.
• Clean and regap.√√
•Replace.√√
3*Valves• Check valve clearance.
•Adjust.√√
4*Fuel injection• Adjust engine idling speed.√√√√√√
5*Mufflers and ex-
haust pipes• Check the screw clamps for
looseness.√√√√√
6*Air induction sys-
tem• Check the air cut-off valve, reed
valve, and hose for damage.
• Replace any damaged parts if
necessary.√√√√√
U2BDE1E0.book Page 3 Tuesday, December 16, 2014 5:38 PM
Page 61 of 98

PERIODIC MAINTENANCE AND ADJUSTMENT
6-17
6
EAU21402
Valve clearanceThe 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.
EAU21647
TiresTires are the only contact between the
vehicle and the road. Safety in all con-
ditions of riding depends on a relatively
small area of road contact. Therefore, it
is essential to maintain the tires in good
condition at all times and replace them
at the appropriate time with the speci-
fied tires.
Tire air pressure
The tire air pressure should be
checked and, if necessary, adjusted
before each ride.
WARNING
EWA10504
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
adjusted in accordance with the
riding speed and with the totalweight of rider, passenger, car-
go, and accessories approved
for this model.
U2BDE1E0.book Page 17 Tuesday, December 16, 2014 5:38 PM
Page 73 of 98

PERIODIC MAINTENANCE AND ADJUSTMENT
6-29
6
EAU23292
Checking the wheel bearingsThe front and rear wheel bearings must
be checked at the intervals specified in
the periodic maintenance and lubrica-
tion chart. If there is play in the wheel
hub or if the wheel does not turn
smoothly, have a Yamaha dealer
check the wheel bearings.
EAUS1913
BatteryTo access the battery (XTZ660Z):
The battery is located under the seat.
(See page 3-16.)
Remove the battery bracket by remov-
ing the bolts.
Battery (XTZ660ZA):
The battery is located under the fuel
tank.Have a Yamaha dealer access the bat-
tery.
These models are equipped with a
VRLA (Valve Regulated Lead Acid) bat-
tery. There is no need to check the
electrolyte or to add distilled water.
However, the battery lead connections
need to be checked and, if necessary,
tightened.
WARNING
EWA10761
Electrolyte is poisonous and
dangerous since it contains sul-
furic acid, which causes severe
burns. Avoid any contact with
skin, eyes or clothing and al-
ways shield your eyes when
1. Positive battery terminal
2. Holder
3. Bolt
4. Negative battery terminal
1. Battery
U2BDE1E0.book Page 29 Tuesday, December 16, 2014 5:38 PM
Page 76 of 98
![YAMAHA XT660Z 2015 Owners Manual PERIODIC MAINTENANCE AND ADJUSTMENT
6-32
6use a fuse of a higher amperage
rating than recommended to
avoid causing extensive dam-
age to the electrical system and
possibly a fire.
[EWA15132]
3. Turn YAMAHA XT660Z 2015 Owners Manual PERIODIC MAINTENANCE AND ADJUSTMENT
6-32
6use a fuse of a higher amperage
rating than recommended to
avoid causing extensive dam-
age to the electrical system and
possibly a fire.
[EWA15132]
3. Turn](/manual-img/51/53212/w960_53212-75.png)
PERIODIC MAINTENANCE AND ADJUSTMENT
6-32
6use a fuse of a higher amperage
rating than recommended to
avoid causing extensive dam-
age to the electrical system and
possibly a fire.
[EWA15132]
3. Turn the key to “ON” and turn on
the electrical circuit in question to
check if the device operates.4. If the fuse immediately blows
again, have a Yamaha dealer
check the electrical system.
EAUB1583
Replacing a headlight bulbThis model is equipped with halogen
bulb headlights. If a headlight bulb
burns out, replace it as follows.NOTICE
ECA10651
Take care not to damage the follow-
ing parts:
Headlight bulb
Do not touch the glass part of
the headlight bulb to keep it free
from oil, otherwise the transpar-
ency of the glass, the luminosity
of the bulb, and the bulb life will
be adversely affected. Thor-
oughly clean off any dirt and fin-
gerprints on the headlight bulb
using a cloth moistened with al-
cohol or thinner.
Headlight lens
Do not affix any type of tinted
film or stickers to the headlight
lens.
Do not use a headlight bulb of a
wattage higher than specified.
Specified fuses:
Main fuse:
30.0 A
Parking lighting fuse:
10.0 A
Signaling system fuse:
10.0 A
Headlight fuse:
20.0 A
Ignition fuse:
10.0 A
Fuel injection system fuse:
10.0 A
Radiator fan motor fuse:
7.5 A
Backup fuse:
10.0 A
ABS motor fuse:
XT660ZA 30.0 A
ABS solenoid fuse:
XT660ZA 20.0 A
ABS control unit fuse:
XT660ZA 5.0 A
U2BDE1E0.book Page 32 Tuesday, December 16, 2014 5:38 PM