2003 YAMAHA YFM660R air filter

OPERATION ...........................................6-1
Starting a cold engine ..........................6-3
Starting a warm engine ........................6-9
Warming up ..........................................6-9
Reverse knob operation and
reverse driving ..................................6-11
Shifting ................................................6-15
To start out and accelerate: ...............6-17
To decelerate: ....................................6-21
Engine break-in ..................................6-23
Parking ...............................................6-27
Parking on a slope ..............................6-29
Accessories and loading ....................6-31
RIDING YOUR ATV..................................7-1
Getting to know your ATV .....................7-3
Ride with care and good judgement .....7-5
Be careful where you ride ...................7-27
Turning your ATV ................................7-39
Climbing uphill.....................................7-45
Riding downhill ....................................7-55
Crossing a slope .................................7-59
Crossing through shallow water ..........7-63
Riding over rough terrain ....................7-67
Sliding and skidding ............................7-69
What to do if .......................................7-73
What to do ..........................................7-73
67
PERIODIC MAINTENANCE AND
ADJUSTMENT ........................................ 8-1
Owner’s manual and tool kit ................. 8-3
Periodic maintenance/lubrication ......... 8-7
Panel removal and installation ........... 8-15
Engine oil and oil filter cartridge ......... 8-17
Cooling system ................................... 8-33
Changing the coolant.......................... 8-35
Spark plug inspection ......................... 8-43
Air filter element cleaning ................... 8-47
Carburetor adjustment ....................... 8-53
Idle speed adjustment ........................ 8-55
Throttle lever adjustment ................... 8-57
Valve clearance adjustment .............. 8-59
Front and rear brake pad inspection... 8-61
Brake fluid level inspection ................. 8-63
Brake fluid replacement ...................... 8-67
Front brake lever free play.................. 8-69
Brake pedal height adjustment ........... 8-71
Parking brake adjustment ................... 8-73
Adjusting the rear brake light switch ... 8-77
Clutch lever free play adjustment ...... 8-79
Drive chain slack check ...................... 8-81
Drive chain slack adjustment .............. 8-83
Lubricating the drive chain ................. 8-85
Cable inspection and lubrication ........ 8-89
8
U5LP62.book Page 2 Wednesday, May 8, 2002 11:24 AM

7-65
1. Check hose
1. Flexible de contrôle
1. Manguito de retención
Test your brakes after leaving the water. Do not
continue to ride your ATV without verifying that
you have regained proper braking ability.CAUTION:_ After riding your ATV in water, be sure to drain
the trapped water by removing the check hose
at the bottom of the air filter case. Wash the
ATV in fresh water if it has been operated in
salt water or muddy conditions. _
U5LP62.book Page 65 Wednesday, May 8, 2002 11:24 AM

8-7
EBU00262
PERIODIC MAINTENANCE/LUBRICATION
ITEM ROUTINEINITIAL EVERY
1
month3
months6
months6
months1
year
Valves*•Check valve clearance.
•Adjust if necessary.
Cooling system•Check coolant leakage.
•Repair if necessary.
•Replace coolant every 24 months.Spark plug•Check condition.
•Adjust gap and clean.
•Replace if necessary.Air filter element•Clean.
•Replace if necessary.Every 20–40 hours
(More often in wet or dusty areas.)
Carburetor*•Check starter (choke) operation.
•Adjust engine idling speed.Crankcase breather
system*•Check breather hose for cracks or damage.
•Replace if necessary.Exhaust system*•Check for leakage.
•Tighten if necessary.
•Replace gasket if necessary.Fuel line*•Check fuel hose for cracks or damage.
•Replace if necessary.Engine oil
•Replace (Warm engine before draining.)Engine oil filter cartridge
•Replace if necessary.Drive chain
•Check and adjust slack/alignment/clean/lube.Front brake*•Check free play/operation/fluid leakage/
See NOTE Page 8-8.
•Correct if necessary.Rear brake*•Check operation/fluid leakage/See NOTE Page 8-8.
•Correct if necessary.Clutch*•Check operation.
•Adjust if necessary.U5LP62.book Page 7 Wednesday, May 8, 2002 11:24 AM

8-47 1. Check hose
1. Flexible de contrôle
1. Manguito de comprobación
1. Air filter case cover 2. Holder (× 6)
1. Couvercle du boîtier de filtre à air 2. Support (× 6)
1. Tapa de la caja del filtro 2. Soporte (× 6)
EBU01212
Air filter element cleaningNOTE:_ There is a check hose at the bottom of the air filter
case. If dust or water collects in this hose, empty
the hose and clean the air filter element and air fil-
ter case. _1. Remove the seat. (See page 4-33 for seat re-
moval and installation procedures.)
2. Remove the air filter case cover by unhook-
ing the holders.
3. Remove the air filter element.
4. Remove the air filter element from its frame.
5. Wash the air filter element gently but thor-
oughly in solvent.
WARNING
_ Always use parts cleaning solvent to clean the
air filter element. Never use low flash point sol-
vents or gasoline to clean the air filter element
because the engine could catch fire or ex-
plode. _
U5LP62.book Page 47 Wednesday, May 8, 2002 11:24 AM

8-49 1. Unlock. 2. Element retaining plate
1. Déverrouiller. 2. Plaquette de retenue d’élément
1. Levántelo. 2. Placa de retención del elemento
1. Frame 2. Air filter element
3. Element retaining plate
1. Armature 2.Élément du filtre à air
3. Plaquette de retenue d’élément
1. Bastidor 2. Elemento del filtro de aire
3. Placa de retención del elemento
6. Squeeze the excess solvent out of the air fil-
ter element and let it dry.CAUTION:_ Do not twist the air filter element when squeez-
ing it. _7. Inspect the air filter element and replace it if
damaged.
8. Apply foam air filter oil to the air filter element.
If foam air filter oil is not available, engine oil
may be used.NOTE:_ The air filter element should be wet but not drip-
ping. _9. Pull the air filter element over its frame.
10. Install the air filter element.
U5LP62.book Page 49 Wednesday, May 8, 2002 11:24 AM

8-51 1. Hose
1. Flexible
1. Manguera
11. Install the air filter case cover and be sure to
connect the hose.
12. Install the seat.NOTE:_ The air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated more
often if the machine is operated in extremely dusty
areas. Each time air filter element maintenance is
performed, check the air inlet to the air filter case
for obstructions. Check the air filter element rubber
joint to the carburetor and manifold fittings for an
airtight seal. Tighten all fittings securely to avoid
the possibility of unfiltered air entering the engine. _CAUTION:_ Never operate the engine with the air filter ele-
ment removed. This will allow unfiltered air to
enter, causing rapid engine wear and possible
engine damage. Additionally, operation with-
out the air filter element will affect carburetor
jetting with subsequent poor performance and
possible engine overheating. _
U5LP62.book Page 51 Wednesday, May 8, 2002 11:24 AM

10-3
Radiator capacity (including all routes) 1.3 L
Air filter Wet element
Fuel:
Type
Tank capacity
Reserve amountUnleaded gasoline only
For Europe: Regular unleaded gasoline only with a
research octane number of 91 or higher
12 L
2.6 L
Carburetor:
Type
× quantity
ManufacturerBSR33
× 1
MIKUNI
Spark plug:
Type/manufacturer
GapDPR8EA-9/NGK
0.8–0.9 mm
Clutch:
Type
OperationWet, multiple-disc
Left hand operation
Transmission:
Primary Reduction System
Primary Reduction Ratio
Secondary Reduction System
Secondary Reduction Ratio
Transmission type
OperationSpur gear
71/34 (2.088)
Chain drive
40/13 (3.076)
Constant mesh, 5-speed forward, 1-speed reverse
Left foot operation MODEL YFM660R
U5LP62.book Page 3 Wednesday, May 8, 2002 11:24 AM