YAMAHA CYGNUS 125 2011 Repair Manual

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EAU1722A
PERIODIC MAINTENANCE AND ADJUSTMENT
EAUT1915
Replacing the fusesThe main fuse box is located above
the battery.ZAUM00**
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1. Main fuseThe fuse box, which contains the fus-
es for the individual circuits, is located
in the storage compartment. (See
page 3-10.)
ZAUM00**
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234
5
6
1. Lid
2. Backup fuse
3. Ignition fuse
4. Signaling system fuse
5. Taillight fuse
6. Headlight fuseIf a fuse is blown, replace it as follows.
1. Turn the key to “OFF” and turn off
the electrical circuit in question.
2. Remove the blown fuse, and then
install a new fuse of the specifi ed
amperage. WARNING! Do not
use a fuse of a higher amper-
age rating than recommended
to avoid causing extensive
damage to the electrical sys-
tem and possibly a re.
[EWA15131]

NOTICE:
After removing and
installing the main fuse, be sure to turn the main switch
from “ON” to “OFF” three
times in 3 seconds intervals to
initialize the idle speed control
system.
[ECAT1062]
Speci ed fuses:
Main fuse:
20 A
Headlight fuse:
15 A
Signaling system fuse:
15 A
Ignition fuse:
7.5 A
Backup fuse:
7.5 A
Taillight fuse:
7.5 A3. Turn the key to “ON” and turn on
the electrical circuit in question to
check if the device operates.
4. If the fuse immediately blows
again, have a Yamaha dealer
check the electrical system.
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EAUT2134
Replacing the headlight bulbThis model is equipped with a halogen
bulb headlight. If the headlight bulb
burns out, replace it as follows.
ECA10650
NOTICETake care not to damage the follow-
ing parts:●
Headlight bulb
Do not touch the glass part of the
headlight bulb to keep it free from
oil, otherwise the transparency
of the glass, the luminosity of the
bulb, and the bulb life will be ad-
versely affected. Thoroughly clean
off any dirt and ngerprints on the
headlight bulb using a cloth moist-
ened with alcohol or thinner.
●
Headlight lens
• Do not af x any type of
tinted lm or stickers to the
headlight lens.
• Do not use a headlight bulb
of a wattage higher than
speci ed.1. Place the vehicle on the center-
stand.
2. Remove panel B. (See page 6-7.)
3. Disconnect the headlight coupler,
and then remove the bulb cover.
ZAUM00**
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1. Bulb cover4. Unhook the headlight bulb holder,
and then remove the burnt-out
bulb.
ZAUM00**
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1. Headlight bulb holder5. Place a new headlight bulb into
position, and then secure it with
the bulb holder.
6. Install the headlight bulb cover,
and then connect the coupler.
7. Install the panel.
8. Have a Yamaha dealer adjust the
headlight beam if necessary.
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EAUT1892
Replacing a front turn signal
light bulb
ECA10670
NOTICEIt is advisable to have a Yamaha
dealer perform this job.
1. Place the scooter on the center-
stand.
2. Remove panel A. (See page 6-7.)
3. Remove the socket (together with
the bulb) by turning it counter-
clockwise.
4. Remove the burnt out bulb by
pushing it in and turning it coun-
terclockwise.ZAUM00**
1
2
1. Turn signal light bulb
2. Socket
5. Insert a new bulb into the socket,
push it in, and then turn it clock-
wise until it stops.
6. Install the socket (together with
the bulb) by turning it clockwise.
7. Install the panel.
EAUT1923
Replacing the tail/brake light
bulb or a rear turn signal light
bulbZAUM00**3
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1. Tail/brake light lens
2. Turn signal light lens
3. Rear turn signal light bulb
4. Tail/brake light bulbTail/brake light bulb
1. Remove the tail/brake light lens
by removing the screws.
2. Remove the burnt out bulb by
pushing it in and turning it coun-
terclockwise.
3. Insert a new bulb into the socket,
push it in, and then turn it clock-
wise until it stops.
4. Install the lens by installing the
screws.
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EAU1722A
PERIODIC MAINTENANCE AND ADJUSTMENTRear turn signal light bulb
1. Remove the tail/brake light lens
by removing the screws.
2. Remove the turn signal light lens
by removing the screws.
3. Remove the burnt out bulb by
pushing it in and turning it coun-
terclockwise.
4. Insert a new bulb into the socket,
push it in, and then turn it clock-
wise until it stops.
5. Install the turn signal light lens by
installing the screws.
6. Install the tail/brake light lens
by installing the screws.
NO-
TICE:
Do not overtighten the
screws, otherwise the lens may
break.[ECA10681]EAUT1963
Replacing an auxiliary light
bulbZAUM00**
12
1. Auxiliary light bulb
2. SocketThis model is equipped with two aux-
iliary lights. If an auxiliary light bulb
burns out, replace it as follows.
1. Remove panel B. (See page 6-7.)
2. Remove the auxiliary light socket
(together with the bulb) by turning
it counterclockwise.
3. Remove the burnt out bulb by
pulling it out.
4. Insert a new bulb into the socket.
5. Install the auxiliary light socket
(together with the bulb) by turning
it clockwise.
6. Install the panel.
EAU25861
TroubleshootingAlthough Yamaha scooters receive a
thorough inspection before shipment
from the factory, trouble may occur
during operation. Any problem in the
fuel, compression, or ignition systems,
for example, can cause poor starting
and loss of power.
The following troubleshooting chart
represents a quick and easy pro-
cedure for checking these vital sys-
tems yourself. However, should your
scooter require any repair, take it to a
Yamaha dealer, whose skilled techni-
cians have the necessary tools, expe-
rience, and know-how to service the
scooter properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life and
can lead to expensive repair bills.
EWA15141
WARNING
When checking the fuel system, do
not smoke, and make sure there
are no open ames or sparks in
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PERIODIC MAINTENANCE AND ADJUSTMENT
the area, including pilot lights from
water heaters or furnaces. Gasoline
or gasoline vapors can ignite or
explode, causing severe injury or
property damage.
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EAUT1981
Troubleshooting chart
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the compression.
Supply fuel.
The engine does not start.
Check the compression.
Operate the electric starter.2. Compression
There is compression.
There is no compression.
Check the ignition.
Have a Yamaha dealer
check the vehicle.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug.
Have a Yamaha dealer check the vehicle.
The engine does not start.
Have a Yamaha dealer
check the vehicle.
The engine does not start.
Check the battery.
Operate the electric starter.4. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.Check the battery lead connections,
and charge the battery if necessary.
DryWet
Operate the electric starter.
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EAU25991
SCOOTER CARE AND STORAGE
EAU25991
SCOOTER CARE AND STORAGE
EAU37833
Matte color caution
ECA15192
NOTICESome models are equipped with
matte colored nished parts. Be
sure to consult a Yamaha dealer for
advice on what products to use be-
fore cleaning the vehicle.
Using a brush, harsh chemical
products or cleaning compounds
when cleaning these parts will
scratch or damage their surface.
Wax also should not be applied to
any matte colored nished parts.
EAU26094
CareWhile the open design of a scooter
reveals the attractiveness of the tech-
nology, it also makes it more vulner-
able. Rust and corrosion can develop
even if high-quality components are
used. A rusty exhaust pipe may go
unnoticed on a car, however, it de-
tracts from the overall appearance of
a scooter. Frequent and proper care
does not only comply with the terms of
the warranty, but it will also keep your
scooter looking good, extend its life
and optimize its performance.
Before cleaning
1. Cover the muffl er outlet with a
plastic bag after the engine has
cooled down.
2. Make sure that all caps and cov-
ers as well as all electrical cou-
plers and connectors, including
the spark plug cap, are tightly
installed.
3. Remove extremely stubborn dirt,
like oil burnt onto the crankcase,
with a degreasing agent and
a brush, but never apply such
products onto seals, gaskets and
wheel axles. Always rinse the dirt
and degreaser off with water.
Cleaning
ECA10783
NOTICE● Avoid using strong acidic
wheel cleaners, especially
on spoked wheels. If such
products are used on hard-to-
remove dirt, do not leave the
cleaner on the affected area
any longer than instructed.
Also, thoroughly rinse the area
off with water, immediately dry
it, and then apply a corrosion
protection spray.● Improper cleaning can dam-
age plastic parts (such as
cowlings, panels, windshields,
headlight lenses, meter lenses,
etc.) and the muf ers. Use only
a soft, clean cloth or sponge
with water to clean plastic.
However, if the plastic parts
cannot be thoroughly cleaned
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with water, diluted mild deter-
gent with water may be used.
Be sure to rinse off any deter-
gent residue using plenty of
water, as it is harmful to plastic
parts.
● Do not use any harsh chemical
products on plastic parts. Be
sure to avoid using cloths or
sponges which have been in
contact with strong or abrasive
cleaning products, solvent or
thinner, fuel (gasoline), rust
removers or inhibitors, brake
uid, antifreeze or electrolyte.● Do not use high-pressure
washers or steam-jet cleaners
since they cause water seep-
age and deterioration in the
following areas: seals (of wheel
and swingarm bearings, fork
and brakes), electric compo-
nents (couplers, connectors,
instruments, switches and
lights), breather hoses and
vents.● For vehicles equipped with a
windshield: Do not use strong
cleaners or hard sponges
as they will cause dulling or
scratching. Some cleaning
compounds for plastic may
leave scratches on the wind-
shield. Test the product on a
small hidden part of the wind-
shield to make sure that it does
not leave any marks. If the
windshield is scratched, use a
quality plastic polishing com-
pound after washing.
After normal use
Remove dirt with warm water, a mild
detergent, and a soft, clean sponge,
and then rinse thoroughly with clean
water. Use a toothbrush or bottlebrush
for hard-to-reach areas. Stubborn dirt
and insects will come off more easily
if the area is covered with a wet cloth
for a few minutes before cleaning.
After riding in the rain, near the sea or on salt-sprayed roadsSince sea salt or salt sprayed on the
roads during winter are extremely cor-
rosive in combination with water, carry
out the following steps after each ride
in the rain, near the sea or on salt-
sprayed roads.TIPSalt sprayed on roads in the winter
may remain well into spring.
1. Clean the scooter with cold water
and a mild detergent after the en-
gine has cooled down.
NOTICE:
Do not use warm water since it
increases the corrosive action
of the salt.
[ECA10791]
2. Apply a corrosion protection
spray on all metal, including
chrome- and nickel-plated, sur-
faces to prevent corrosion.
After cleaning
1. Dry the scooter with a chamois or
an absorbing cloth.
2. Use a chrome polish to shine
chrome, aluminum and stainless-
steel parts, including the exhaust
system. (Even the thermally in-
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duced discoloring of stainless-
steel exhaust systems can be
removed through polishing.)
3. To prevent corrosion, it is recom-
mended to apply a corrosion pro-
tection spray on all metal, includ-
ing chrome- and nickel-plated,
surfaces.
4. Use spray oil as a universal
cleaner to remove any remaining
dirt.
5. Touch up minor paint damage
caused by stones, etc.
6. Wax all painted surfaces.
7. Let the scooter dry completely
before storing or covering it.
EWA10942
WARNING
Contaminants on the brakes or
tires can cause loss of control.● Make sure that there is no oil
or wax on the brakes or tires.
If necessary, clean the brake
discs and brake linings with a
regular brake disc cleaner or
acetone, and wash the tires
with warm water and a mild de-
tergent.
● Before operating the vehicle,
test its braking performance
and cornering behavior.
ECA10800
NOTICE● Apply spray oil and wax spar-
ingly and make sure to wipe off
any excess.● Never apply oil or wax to any
rubber and plastic parts, but
treat them with a suitable care
product.● Avoid using abrasive polishing
compounds as they will wear
away the paint.
TIP● Consult a Yamaha dealer for ad-
vice on what products to use.● Washing, rainy weather or humid
climates can cause the headlight
lens to fog. Turning the headlight
on for a short period of time will
help remove the moisture from
the lens.
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2. Fill up the fuel tank and add fuel
stabilizer (if available) to prevent
the fuel tank from rusting and the
fuel from deteriorating.
3. Perform the following steps to
protect the cylinder, piston rings,
etc. from corrosion.
a. Remove the spark plug cap
and spark plug.
b. Pour a teaspoonful of engine
oil into the spark plug bore.
c. Install the spark plug cap onto
the spark plug, and then place
the spark plug on the cylinder
head so that the electrodes are
grounded. (This will limit spark-
ing during the next step.)
d. Turn the engine over several
times with the starter. (This will
coat the cylinder wall with oil.)
e. Remove the spark plug cap
from the spark plug, and then
install the spark plug and the
spark plug cap. WARNING!
To prevent damage or injury
from sparking, make sure to
ground the spark plug elec-
trodes while turning the en-gine over.
[EWA10951]
4. Lubricate all control cables and
the pivoting points of all levers
and pedals as well as of the
sidestand/centerstand.
5. Check and, if necessary, correct
the tire air pressure, and then
lift the scooter so that both of its
wheels are off the ground. Alter-
natively, turn the wheels a little
every month in order to prevent
the tires from becoming degraded
in one spot.
6. Cover the muffl er outlet with a
plastic bag to prevent moisture
from entering it.
7. Remove the battery and fully
charge it. Store it in a cool,
dry place and charge it once a
month. Do not store the battery
in an excessively cold or warm
place [less than 0 °C (30 °F) or
more than 30 °C (90 °F)]. For
more information on storing the
battery, see page 6-24.
EAU36563
StorageShort-term
Always store your scooter in a cool,
dry place and, if necessary, protect
it against dust with a porous cover.
Be sure the engine and the exhaust
system are cool before covering the
scooter.
ECA10820
NOTICE● Storing the scooter in a poorly
ventilated room or covering it
with a tarp, while it is still wet,
will allow water and humidity to
seep in and cause rust.● To prevent corrosion, avoid
damp cellars, stables (because
of the presence of ammonia)
and areas where strong chemi-
cals are stored.
Long-term
Before storing your scooter for several
months:
1. Follow all the instructions in the
“Care” section of this chapter.
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