Page 11 of 90

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.
Page 82 of 90

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
Page 84 of 90

SPECIFICATIONS
8-3
8
Front suspension:Type:
Telescopic fork
Spring/shock absorber type:
Coil spring/oil damper
Wheel travel:
XT660R 225.0 mm (8.86 in)
XT660X 200.0 mm (7.87 in)Rear suspension:Type:
Swingarm (monocross)
Spring/shock absorber type:
Coil spring/gas-oil damper
Wheel travel:
XT660R 200.0 mm (7.87 in)
XT660X 191.0 mm (7.52 in)Electrical system:Ignition system:
Transistorized coil ignition (digital)
Charging system:
A.C. magnetoBattery:Model:
GT9B-4
Voltage, capacity:
12 V, 8.0 AhHeadlight:Bulb type:
Halogen bulbBulb voltage, wattage x quantity:Headlight:
12 V, 55 W/60.0 W × 1
Tail/brake light:
12 V, 5.0/21.0 W × 1Front turn signal light:
12 V, 10.0 W × 2
Rear turn signal light:
12 V, 10.0 W × 2
Auxiliary light:
12 V, 5.0 W × 1
Meter lighting:
EL
Neutral indicator light:
LED
High beam indicator light:
LED
Turn signal indicator light:
LED
Fuel level warning light:
LED
Coolant temperature indicator light:
LED
Engine trouble warning light:
LED
Immobilizer system indicator light:
LED
Fuses:Main fuse:
30.0 A
Headlight fuse:
20.0 A
Signaling system fuse:
10.0 A
Ignition fuse:
10.0 A
Parking lighting fuse:
10.0 ARadiator fan fuse:
7.5 A
Electronic fuel injection fuse:
10.0 A
Backup fuse:
10.0 A