light YAMAHA YFM660R 2003 Owner's Manual

8-43 1. Spark plug cap
1. Capuchon de bougie
1. Tapa de bujía
1. Spark plug wrench
1. Clé à bougie
1. Llave de bujía
EBU00680
Spark plug inspection
Removal
1. Remove the spark plug cap.
2. Use the spark plug wrench in the tool kit to re-
move the spark plug as shown.
Inspection
The spark plug is an important engine component
and is easy to inspect. The condition of the spark
plug can indicate the condition of the engine.
The ideal color on the white insulator around the
center electrode is a medium-to-light tan color for a
ATV that is being ridden normally.
Do not attempt to diagnose such problems your-
self.
Instead, take the ATV to a Yamaha dealer. You
should periodically remove and inspect the spark
plug because heat and deposits will cause the
spark plug to slowly break down and erode. If elec-
trode erosion becomes excessive, or if carbon and
other deposits are excessive, you should replace
the spark plug with the specified plug.
U5LP62.book Page 43 Wednesday, May 8, 2002 11:24 AM

8-77 1. Rear brake light switch
2. Adjusting nut
1. Contacteur de feu stop sur frein arrière
2.Écrou de réglage
1. Interruptor de la luz de freno trasero
2. Tuerca de ajuste
EBU00833
Adjusting the rear brake light switch
The rear brake light switch, which is activated by
the brake pedal and brake lever, is properly adjust-
ed when the brake light comes on just before brak-
ing takes effect. If necessary, adjust the brake light
switch as follows.
Turn the adjusting nut while holding the rear brake
light switch in place. To make the brake light come
on earlier, turn the adjusting nut in direction
a. To
make the brake light come on later, turn the adjust-
ing nut in direction
b.
U5LP62.book Page 77 Wednesday, May 8, 2002 11:24 AM

8-109 1. Headlight assembly 2. Bolt (× 2)
1. Bloc de phare 2. Boulon (× 2)
1. Conjunto faro 2. Perno (× 2)
1. Headlight coupler
1. Coupleur de phare
1. Acoplador del faro
EBU01216
Replacing a headlight bulb
If a headlight bulb burns out, replace the bulb as
follows.
1. Remove the headlight assembly by removing
the bolts.
2. Disconnect the headlight coupler.
U5LP62.book Page 109 Wednesday, May 8, 2002 11:24 AM

8-111 1. Screw
1. Vis
1. Tornillo
1. Screw
1. Vis
1. Tornillo
3. Remove the screw.
4. Remove the headlight cover from the head-
light assembly.
5. Remove the screw and pull the headlight unit
out from its case.NOTE:_ Pull outward on the rear of the headlight unit, and
then pull outward on the front. _
U5LP62.book Page 111 Wednesday, May 8, 2002 11:24 AM

8-113 1. Headlight bulb holder cover
1. Cache de la fixation d’ampoule de phare
1. Cubierta del portabombillas del faro
1. Headlight bulb holder
1. Fixation d’ampoule de phare
1. Portabombillas del faro
6. Remove the headlight bulb holder cover.
7. Push the headlight bulb holder inward, turn it
counterclockwise and remove the defective
bulb.
WARNING
_ A headlight bulb is hot when it is on and imme-
diately after it is turned off. Wait for the bulb to
cool down before touching or removing it. You
can be burned, or a fire could start if the bulb
touches something flammable. _
U5LP62.book Page 113 Wednesday, May 8, 2002 11:24 AM

8-115 1. Headlight bulb 2. Headlight bulb holder
1. Ampoule de phare 2. Fixation d’ampoule
1. Bonbilla del faro 2. Portabombillas del faro
1. Headlight unit 2. Headlight case
1. Optique de phare 2. Support du phare
1. Unidad del faro 2. Caja del faro
8. Put a new headlight bulb into position and se-
cure it in place with the bulb holder.
9. Install the headlight bulb holder cover.CAUTION:_ Make sure the headlight bulb holder cover is
securely fitted over the bulb holder and seated
against the reflector. _10. Align the projections on the headlight unit
with the holders, install the headlight unit into
the case, and then install the screw.
11. Place the headlight cover in the original posi-
tion, and then install the screw.
U5LP62.book Page 115 Wednesday, May 8, 2002 11:24 AM

8-117
12. Connect the headlight coupler.
13. Place the headlight assembly in the original
position, and then install the bolts.
14. Have a Yamaha dealer adjust the headlight
beam if necessary.
U5LP62.book Page 117 Wednesday, May 8, 2002 11:24 AM

8-119 1. Lens 2. Screw (× 2)
1. Lentille 2. Vis (× 2)
1. Lente 2. Tornillo (× 2)
1. Bulb
1. Ampoule
1. Bombilla
EBU01217
Tail/brake light bulb replacement
1. Remove the lens by removing the screws.
2. Remove the defective bulb by pushing it in-
ward and turning it counterclockwise.
3. Install a new bulb by pushing it inward and
turning it clockwise.
4. Install the lens by installing the screws.CAUTION:_ Do not overtighten the screws as the lens may
break. _
U5LP62.book Page 119 Wednesday, May 8, 2002 11:24 AM

8-121
EBU00413
Troubleshooting
Although Yamaha machines receive a rigid in-
spection before shipment from the factory, trouble
may occur during operation.
Any problem in the fuel, compression, or ignition
systems can cause poor starting and loss of pow-
er. The troubleshooting chart describes a quick,
easy procedure for making checks. If your ma-
chine requires any repair, take it to a Yamaha
dealer.
The skilled technicians at a Yamaha dealership
have the tools, experience, and know-how to prop-
erly service your machine. Use only genuine
Yamaha parts on your machine. Imitation parts
may look like Yamaha parts, but they are often in-
ferior. Consequently, they have a shorter service
life and can lead to expensive repair bills.
WARNING
Do not smoke when checking the fuel system.
Fuel can ignite or explode, causing severe in-
jury or property damage. Make sure there are
no open flames or sparks in the area, including
pilot lights from water heaters or furnaces.
U5LP62.book Page 121 Wednesday, May 8, 2002 11:24 AM

9-9
5. Block up the frame to raise all wheels off the
ground.
6. Tie a plastic bag over the exhaust pipe outlet
to prevent moisture from entering.
7. If storing in a humid or salt-air atmosphere,
coat all exposed metal surfaces with a light
film of oil. Do not apply oil to any rubber parts
or the seat cover.
8. Remove the battery and charge it. Store it in
a dry place and recharge it once a month. Do
not store the battery in an excessively warm
or cold place (less than 0°C or more than
30°C).NOTE:Make any necessary repairs before storing the
machine.
U5LP62.book Page 9 Wednesday, May 8, 2002 11:24 AM