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 of
186 kg (410 lb). When loading within
this weight limit, keep the following in
mind:
SAFETY INFORMATION
1-3
1
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-Yamahaaccessories. 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.
PERIODIC MAINTENANCE AND MINOR REPAIR
6-17
6
EAU21380
Adjusting the throttle cable
free play The throttle cable free play should mea-
sure 3.0–5.0 mm (0.12–0.20 in) at the
throttle grip. Periodically check the
throttle cable free play and, if neces-
sary, have a Yamaha dealer adjust it.
EAU21640
TiresTo 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.
WARNING
EWA10500
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 ad-
justed in accordance with the
riding speed and with the total
weight of rider, passenger, car-
go, and accessories approvedfor this model.
1. Throttle cable free play
Tire air pressure (measured on cold
tires):
0–90 kg (0–198 lb):
Fr o nt :
XT660R 200 kPa (29 psi) (2.00
kgf/cm²)
XT660X 210 kPa (30 psi) (2.10
kgf/cm²)
Rear:
XT660R 200 kPa (29 psi) (2.00
kgf/cm²)
XT660X 210 kPa (30 psi) (2.10
kgf/cm²)
90–186 kg (198–410 lb):
Fr o nt :
XT660R 200 kPa (29 psi) (2.00
kgf/cm²)
XT660X 220 kPa (32 psi) (2.20
kgf/cm²)
Rear:
XT660R 225 kPa (33 psi) (2.25
kgf/cm²)
XT660X 230 kPa (33 psi) (2.30
kgf/cm²)
Off-road riding:
Fr o nt :
XT660R 200 kPa (29 psi) (2.00
kgf/cm²)
Rear:
XT660R 200 kPa (29 psi) (2.00
kgf/cm²)
Maximum load*:
186 kg (410 lb)
* Total weight of rider, passenger, car-
go and accessories
PERIODIC MAINTENANCE AND MINOR REPAIR
6-18
6
WARNING
EWA11020
Because loading has an enormous
impact on the handling, braking,
performance and safety characteris-
tics of your motorcycle, you should
keep the following precautions in
mind.
NEVER OVERLOAD THE
MOTORCYCLE! Operation of an
overloaded motorcycle may re-
sult in tire damage, loss of con-
trol, or severe injury. Make sure
that the total weight of rider,
passenger, cargo, and accesso-
ries does not exceed the speci-
fied maximum load for the
vehicle.
Do not carry along loosely
packed items, which can shift
during a ride.
Securely pack the heaviest
items close to the center of the
motorcycle and distribute the
weight evenly on both sides.
Adjust the suspension and tire
air pressure with regard to the
load.
Check the tire condition and airpressure before each ride.
Tire inspection
The tires must be checked before each
ride. If the center tread depth reaches
the specified limit, if the tire has a nail or
glass fragments in it, or if the sidewall is
cracked, have a Yamaha dealer re-
place the tire immediately.
NOTE:The tire tread depth limits may differ
from country to country. Always complywith the local regulations.
Tire information
This motorcycle is equipped with tube
tires.
WARNING
EWA10460
The front and rear tires should
be of the same make and de-
sign, otherwise the handling
characteristics of the vehicle
cannot be guaranteed.
After extensive tests, only the
tires listed below have been ap-
proved for this model byYamaha Motor Co., Ltd.
1. Tire sidewall
2. Tire tread depthMinimum tire tread depth (front and
rear):
1.6 mm (0.06 in)
PERIODIC MAINTENANCE AND MINOR REPAIR
6-23
6
EAU22760
Drive chain slack The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU22780
To check the drive chain slack
1. Place the motorcycle on a level
surface and hold it in an upright po-
sition.NOTE:When checking and adjusting the drive
chain slack, the motorcycle should be
positioned straight up and there shouldbe no weight on it.
2. Shift the transmission into the neu-
tral 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 incorrect,
adjust it as follows.
NOTE:When checking the drive chain slack,
the chain tensioner should not betouching the drive chain.
EAU22930
To adjust the drive chain slack
1. Loosen the axle nut, then loosen
the locknut at each end of the
swingarm.
2. To tighten the drive chain, turn the
adjusting nut at each end of the
swingarm in direction (a). To loos-
en the drive chain, turn the adjust-
ing nut at each end 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 adjusting nuts are in the same po-sition for proper wheel alignment.CAUTION:
ECA10570
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 thespecified limits.
1. Drive chain slack
Drive chain slack:
40.0–55.0 mm (1.57–2.17 in)
1. Axle nut
2. Drive chain slack adjusting nut
3. Locknut
4. Alignment marks
SPECIFICATIONS
8-1
8
Dimensions:Overall length:
XT660R 2240 mm (88.2 in)
XT660X 2150 mm (84.6 in)
Overall width:
XT660R 845 mm (33.3 in)
XT660X 865 mm (34.1 in)
Overall height:
XT660R 1230 mm (48.4 in)
XT660X 1210 mm (47.6 in)
Seat height:
XT660R 865 mm (34.1 in)
XT660X 870 mm (34.3 in)
Wheelbase:
XT660R 1505 mm (59.3 in)
XT660X 1490 mm (58.7 in)
Ground clearance:
XT660R 210 mm (8.27 in)
XT660X 205 mm (8.07 in)
Minimum turning radius:
2400 mm (94.5 in)Weight:With oil and fuel:
XT660R 181.0 kg (399 lb)
XT660X 186.0 kg (410 lb)Engine:Engine type:
Liquid cooled 4-stroke, SOHC
Cylinder arrangement:
Forward-inclined single cylinder
Displacement:
660.0 cm³ (40.27 cu.in)
Bore × stroke:
100.0 × 84.0 mm (3.94 × 3.31 in)Compression ratio:
10.00 :1
Starting system:
Electric starter
Lubrication system:
Dry sump
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) (2.20 Imp.qt)
With oil filter element replacement:
2.60 L (2.75 US qt) (2.29 Imp.qt)Cooling system:Coolant reservoir capacity (up to the
maximum level mark):
0.25 L (0.26 US qt) (0.22 Imp.qt)
Radiator capacity (including all routes):
1.00 L (1.06 US qt) (0.88 Imp.qt)
Air filter:Air filter element:
Oil-coated paper elementFuel:Recommended fuel:
Premium unleaded gasoline only
Fuel tank capacity:
15.0 L (3.96 US gal) (3.30 Imp.gal)
Fuel reserve amount:
5.0 L (1.32 US gal) (1.10 Imp.gal)Electronic fuel injection:Manufacturer:
DENSO
Model:
297500-0390Spark plug(s):Manufacturer/model:
NGK/CR7E
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)Clutch:Clutch type:
Wet, multiple-discTransmission:Primary reduction system:
Spur gear
Primary reduction ratio:
75/36 (2.083)
Secondary reduction system:
Chain drive
Secondary reduction ratio:
45/15 (3.000)
Transmission type:
Constant mesh 5-speed
-20 -10 0
10 20 30
40
50 ˚C
SAE 10W-30
SAE 15W-40SAE 20W-40SAE 20W-50
SAE 10W-40
SPECIFICATIONS
8-2
8
Operation:
Left foot operation
Gear ratio:
1st:
30/12 (2.500)
2nd:
26/16 (1.625)
3rd:
23/20 (1.150)
4th:
20/22 (0.909)
5th:
20/26 (0.769)Chassis:Frame type:
Diamond
Caster angle:
XT660R 27.25 °
XT660X 26.00 °
Trail:
XT660R 107.0 mm (4.21 in)
XT660X 94.0 mm (3.70 in)Front tire:Type:
With tube
Size:
XT660R 90/90-21M/C 54S, 90/90-21M/C
54T
XT660X 120/70R17 M/C 58H
Manufacturer/model:
XT660R METZELER/TOURANCE FRONT
XT660X PIRELLI/DRAGON
Manufacturer/model:
XT660R MICHELIN/SIRAC
Rear tire:Type:
With tube
Size:
XT660R 130/80-17M/C 65S, 130/80-
17M/C 65T
XT660X 160/60R17 M/C 69H
Manufacturer/model:
XT660R METZELER/TOURANCE
XT660X PIRELLI/DRAGON
Manufacturer/model:
XT660R MICHELIN/SIRAC ALoading:Maximum load:
186 kg (410 lb)
(Total weight of rider, passenger, cargo and
accessories)Tire air pressure (measured on cold
tires):Loading condition:
0–90 kg (0–198 lb)
Front:
XT660R 200 kPa (29 psi) (2.00 kgf/cm²)
XT660X 210 kPa (30 psi) (2.10 kgf/cm²)
Rear:
XT660R 200 kPa (29 psi) (2.00 kgf/cm²)
XT660X 210 kPa (30 psi) (2.10 kgf/cm²)
Loading condition:
90–186 kg (198–410 lb)
Front:
XT660R 200 kPa (29 psi) (2.00 kgf/cm²)
XT660X 220 kPa (32 psi) (2.20 kgf/cm²)Rear:
XT660R 225 kPa (33 psi) (2.25 kgf/cm²)
XT660X 230 kPa (33 psi) (2.30 kgf/cm²)
Off-road riding:
Front:
XT660R 200 kPa (29 psi) (2.00 kgf/cm²)
Rear:
XT660R 200 kPa (29 psi) (2.00 kgf/cm²)
Front wheel:Wheel type:
Spoke wheel
Rim size:
XT660R 21x1.85
XT660X 17M/C x MT3.50Rear wheel:Wheel type:
Spoke wheel
Rim size:
XT660R 17M/C x MT2.75
XT660X 17M/C x MT4.25Front brake:Type:
Single disc brake
Operation:
Right hand operation
Recommended fluid:
DOT 4Rear brake:Type:
Single disc brake
Operation:
Right foot operation
Recommended fluid:
DOT 4