2008 YAMAHA XT660X air filter

PERIODIC MAINTENANCE AND MINOR REPAIR
6-17
6
CAUTION:
ECA10480


Make sure that the air filter ele-
ment is properly seated in the
air filter case.


The engine should never be op-
erated without the air filter ele-
ment installed, otherwise the
piston(s) and/or cylinder(s) maybecome excessively worn.
6. Install the air filter case cover by in-
stalling the screws.
7. Install the panel.
8. Install the seat.
To clean the air filter check hose
1. Check the hose on the side of the
air filter case for accumulated dirt
or water.2. If dirt or water is visible, remove
the hose, clean it, and then install
it.
EAUM1910
Adjusting the engine idling
speed The engine idling speed must be
checked and, if necessary, adjusted as
follows at the intervals specified in the
periodic maintenance and lubrication
chart.
The engine should be warm before
making this adjustment.NOTE:

The engine is warm when it quickly
responds to the throttle.


A diagnostic tachometer is neededto make this adjustment.
1. Attach the tachometer to the spark
plug lead.
2. Check the engine idling speed
and, if necessary, adjust it to spec-
ification by turning the idle adjust-
ing screw. To increase the engine
idling speed, turn the screw in di-
rection (a). To decrease the en-
gine idling speed, turn the screw in
direction (b).
1. Air filter check hose
U5VKE1E0.book Page 17 Tuesday, July 18, 2006 1:00 PM

SPECIFICATIONS
8-1
8
Dimensions:Overall length:
XT660R 2240 mm (88.2 in)
XT660X 2175 mm (85.6 in)
Overall width:
XT660R 845 mm (33.3 in)
XT660X 860 mm (33.9 in)
Overall height:
XT660R 1230 mm (48.4 in)
XT660X 1170 mm (46.1 in)
Seat height:
XT660R 865 mm (34.1 in)
XT660X 875 mm (34.4 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
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, SAE10W40, SAE15W40,
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)Fuel injector:Manufacturer:
DENSO
Model/quantity:
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
U5VKE1E0.book Page 1 Tuesday, July 18, 2006 1:00 PM

INDEX
AAir filter element and check hose,
replacing and cleaning ....................... 6-16
Anti-theft alarm (optional) ....................... 3-7
Auxiliary light bulb, replacing ................ 6-35BBattery .................................................. 6-30
Brake and clutch levers, checking and
lubricating ........................................... 6-27
Brake fluid level, checking .................... 6-23
Brake lever ............................................. 3-9
Brake pedal .......................................... 3-10
Brake pedal, lubricating ........................ 6-28CCables, checking and lubricating .......... 6-27
Care ........................................................ 7-1
Catalytic converter ................................ 3-12
Clutch lever............................................. 3-9
Clutch lever free play, adjusting ........... 6-21
Coolant ................................................. 6-13
Coolant temperature warning light.......... 3-4
Cowlings and panels, removing and
installing ............................................... 6-5DDimmer switch ........................................ 3-8
Drive chain, cleaning and lubricating .... 6-26
Drive chain slack .................................. 6-24EEngine break-in ...................................... 5-3
Engine idling speed .............................. 6-17
Engine oil and oil filter element............. 6-10
Engine stop switch.................................. 3-8
Engine trouble warning light ................... 3-4
FFront and rear brake pads, checking .... 6-22
Front fork, checking...............................6-29
Fuel ....................................................... 3-11
Fuel consumption, tips for reducing ........ 5-3
Fuel level warning light............................ 3-4
Fuel tank cap......................................... 3-10
Fuses, replacing .................................... 6-32HHandlebar switches ................................. 3-7
Hazard switch.......................................... 3-8
Headlight bulb, replacing....................... 6-33
High beam indicator light......................... 3-4
Horn switch ............................................. 3-8IIdentification numbers ............................. 9-1
Ignition circuit cut-off system ................. 3-15
Immobilizer system .................................3-1
Immobilizer system indicator light ........... 3-4
Indicator and warning lights .................... 3-3KKey identification number ........................ 9-1MMain switch/steering lock ........................ 3-2
Model label .............................................. 9-2
Multi-function display...............................3-5NNeutral indicator light .............................. 3-3PParking ....................................................5-4
Part locations .......................................... 2-1
Pass switch ............................................. 3-8
Periodic maintenance and lubrication
chart ......................................................6-2Pre-operation check list .......................... 4-2
RRear brake light switch, adjusting ......... 6-22SSafety information ................................... 1-1
Seat ...................................................... 3-12
Shifting .................................................... 5-2
Shift pedal ............................................... 3-9
Shock absorber assembly, adjusting .... 3-13
Sidestand .............................................. 3-14
Sidestand, checking and lubricating ..... 6-28
Spark plug, checking .............................. 6-9
Specifications.......................................... 8-1
Starting the engine.................................. 5-1
Start switch ............................................. 3-8
Steering, checking ................................ 6-29
Storage ................................................... 7-3
Storage compartment ........................... 3-13
Supporting the motorcycle .................... 6-35TThrottle cable free play, checking ......... 6-18
Throttle grip and cable, checking and
lubricating ........................................... 6-27
Tires ...................................................... 6-18
Tool kit .................................................... 6-1
Troubleshooting .................................... 6-39
Troubleshooting charts ......................... 6-40
Turn signal indicator light ........................ 3-3
Turn signal light bulb or tail/brake light
bulb, replacing .................................... 6-34
Turn signal switch ................................... 3-8VVehicle identification number .................. 9-1
U5VKE1E0.book Page 1 Tuesday, July 18, 2006 1:00 PM