2011 YAMAHA CYGNUS 125 fuel cap

TABLE OF CONTENTSSAFETY INFORMATION .................... 1-1
Further safe-riding points ................. 1-5
DESCRIPTION .................................... 2-1
Left view ........................................... 2-1
Right view......................................... 2-2
Controls and instruments ................. 2-3
INSTRUMENT AND CONTROL FUNC-
TIONS.................................................. 3-1
Main switch/steering lock ................. 3-1
Keyhole cover .................................. 3-2
Indicator and warning lights ............. 3-2
Speedometer.................................... 3-3
Multi-function display........................ 3-3
Handlebar switches .......................... 3-5
Front brake lever .............................. 3-6
Rear brake lever............................... 3-6
Fuel tank cap.................................... 3-7
Fuel .................................................. 3-7
Catalytic converters.......................... 3-9
Kickstarter ........................................ 3-9
Seat ................................................ 3-10
Storage compartments ................... 3-10
Sidestand ....................................... 3-11
Ignition circuit cut-off system .......... 3-12
FOR YOUR SAFETY - PRE-OPERATION
CHECKS ............................................. 4-1OPERATION AND IMPORTANT RIDING
POINTS ............................................... 5-1
Starting the engine ........................... 5-1
Starting off ........................................ 5-2
Acceleration and deceleration .......... 5-2
Braking ............................................. 5-2
Tips for reducing fuel consumption .. 5-3
Engine break-in ................................ 5-3
Parking ............................................. 5-4
PERIODIC MAINTENANCE AND AD-
JUSTMENT ......................................... 6-1
Owner’s tool kit................................. 6-2
Periodic maintenance chart for the
emission control system ............... 6-3
General maintenance and lubrication
chart .............................................. 6-4
Removing and installing panels ....... 6-7
Checking the spark plug................... 6-8
Engine oil and oil strainer ............... 6-10
Final transmission oil...................... 6-12
Air fi lter and V-belt case air fi lter
elements ..................................... 6-13
Checking the throttle grip free
play ............................................. 6-15
Valve clearance.............................. 6-15
Tires ............................................... 6-16
Cast wheels.................................... 6-17
Checking the brake lever free
play ............................................. 6-18Adjusting the rear brake lever free
play ............................................. 6-18
Checking the front brake pads and
rear brake shoes ......................... 6-19
Checking the brake fl uid level ........ 6-19
Changing the brake fl uid ................ 6-20
Checking and lubricating the
cables ......................................... 6-21
Checking and lubricating the throttle grip
and cable .................................... 6-21
Lubricating the front and rear brake
levers .......................................... 6-21
Checking and lubricating the
centerstand and sidestand.......... 6-22
Checking the front fork ................... 6-23
Checking the steering .................... 6-23
Checking the wheel bearings ......... 6-24
Battery ............................................ 6-24
Replacing the fuses........................ 6-26
Replacing the headlight bulb .......... 6-27
Replacing a front turn signal light
bulb ............................................. 6-28
Replacing the tail/brake light bulb or a
rear turn signal light bulb ............ 6-28
Replacing an auxiliary light bulb..... 6-29
Troubleshooting ............................. 6-29
Troubleshooting chart .................... 6-31
SCOOTER CARE AND STORAGE .... 7-1
Matte color caution ........................... 7-1
Care ................................................. 7-1
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EAU10401
DESCRIPTION1. Fuel tank cap (page 3-7)
2. Rear storage compartment (page 3-10)
3. Rear turn signal light (page 6-28)
4. Tail/brake light (page 6-28)
5. Kickstarter (page 3-9)
6. Air fi lter (page 6-13)
EAU10410
Left view
EAU10401
DESCRIPTION
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EAU1044E
INSTRUMENT AND CONTROL FUNCTIONS
EAU13074
Fuel tank capTo open the fuel tank cap
Open the fuel tank cap lock cover,
insert the key into the lock, and then
turn it 1/4 turn clockwise. The lock will
be released and the fuel tank cap can
be opened.ZAUM00**
1
1. Fuel tank cap lock coverTo close the fuel tank cap
1. Push the fuel tank cap into posi-
tion with the key inserted in the
lock.
2. Turn the key counterclockwise to
the original position, remove it,
and then close the lock cover.
TIPThe fuel tank cap cannot be closed
unless the key is in the lock. In addi-
tion, the key cannot be removed if the
cap is not properly closed and locked.
EWA11091
WARNING
Make sure that the fuel tank cap
is properly closed after lling fuel.
Leaking fuel is a re hazard.
EAU13221
FuelZAUM00**
1
2
1. Fuel tank fi ller tube
2. Fuel levelMake sure there is suffi cient gasoline
in the tank.
EWA10881
WARNING
Gasoline and gasoline vapors are
extremely ammable. To avoid res
and explosions and to reduce the
risk of injury when refueling, follow
these instructions.
1. Before refueling, turn off the en-
gine and be sure that no one is
sitting on the vehicle. Never re-
fuel while smoking, or while in the
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EAU1044E
INSTRUMENT AND CONTROL FUNCTIONS
vicinity of sparks, open fl ames, or
other sources of ignition such as
the pilot lights of water heaters
and clothes dryers.
2. Do not overfi ll the fuel tank. When
refueling, be sure to insert the
pump nozzle into the fuel tank fi ll-
er hole. Stop fi lling when the fuel
reaches the bottom of the fi ller
tube. Because fuel expands when
it heats up, heat from the engine
or the sun can cause fuel to spill
out of the fuel tank.
3. Wipe up any spilled fuel im-
mediately.
NOTICE:
Immedi-
ately wipe off spilled fuel with a
clean, dry, soft cloth, since fuel
may deteriorate painted sur-
faces or plastic parts.[ECA10071]
4. Be sure to securely close the fuel
tank cap.
EWA15151
WARNING
Gasoline is poisonous and can
cause injury or death. Handle
gasoline with care. Never siphon
gasoline by mouth. If you should
swallow some gasoline or inhale a
lot of gasoline vapor, or get some
gasoline in your eyes, see your
doctor immediately. If gasoline
spills on your skin, wash with soap
and water. If gasoline spills on your
clothing, change your clothes.
EAU33520
Recommended fuel:
REGULAR UNLEADED GASO-
LINE ONLY
Fuel tank capacity:
7.4 L (1.96 US gal) (1.63 Imp.gal)
ECA11400
NOTICEUse only unleaded gasoline. The
use of leaded gasoline will cause
severe damage to internal engine
parts, such as the valves and pis-
ton rings, as well as to the exhaust
system.
Your Yamaha engine has been de-
signed to use regular unleaded gaso-
line with a research octane number of
91 or higher. If knocking (or pinging)
occurs, use a gasoline of a different
brand or premium unleaded fuel. Use of unleaded fuel will extend spark plug
life and reduce maintenance costs.
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EAU25991
SCOOTER CARE AND STORAGE
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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8-1
SPECIFICATIONS SPECIFICATIONS
EAU50910
DimensionsOverall length
1855 mm (73.0 in)
Overall width
685 mm (27.0 in)
Overall height
1130 mm (44.5 in)
Seat height
785 mm (30.9 in)
Wheelbase
1295 mm (51.0 in)
Ground clearance
113 mm (4.45 in)
Minimum turning radius
1900 mm (74.8 in)WeightCurb weight
120 kg (265 lb)EngineEngine type
Air cooled 4-stroke, SOHC
Cylinder arrangement
Single cylinder
Displacement
125 cm
3
Bore x stroke
52.4 x 57.9 mm (2.06 x 2.28 in)
Compression ratio
10.00 :1
Starting system
Electric starter and kickstarter
Lubrication system
Wet sump
Engine oilRecommended brand
YAMALUBE
Type
SAE 10W-30, 10W-40, 10W-50, 15W-40,
20W-40 or 20W-50
–20 –10 0
1020 30 40 50 ˚C 10 30 50 70 90 110 0 130 ˚F
SAE 10W-30
SAE 15W-40SAE 20W-40SAE 20W-50
SAE 10W-40SAE 10W-50
Recommended engine oil grade
API service SG type or higher, JASO
standard MAEngine oil quantityPeriodic oil change
0.90 L (0.95 US qt, 0.79 Imp.qt)Final transmission oilType
SAE 10W-30 type SE motor oil
Quantity
0.11 L (0.12 US qt, 0.10 Imp.qt)Air lterAir fi lter element
Wet elementFuelRecommended fuel
Regular unleaded gasoline onlyFuel tank capacity
7.4 L (1.96 US gal, 1.63 Imp.gal)
Throttle bodyID mark
4P91 00
Manufacturer
MIKUNISpark plug(s)Manufacturer/model
NGK/CR7E
Spark plug gap
0.7-0.8 mm (0.028-0.031 in)ClutchClutch type
Dry, centrifugal automaticTransmissionPrimary reduction ratio
1.000
Secondary reduction ratio
9.744 (38/13 40/12)
Final drive
Gear
Transmission type
V-belt automaticChassisFrame type
Backbone
Caster angle
27.00 degree
Trail
90 mm (3.5 in)Front tireType
Tubeless
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INDEXAAcceleration and deceleration................... 5-2
Air fi lter and V-belt case air fi lter
elements ............................................... 6-13
Auxiliary light bulb, replacing .................. 6-29BBattery..................................................... 6-24
Brake fl uid, changing .............................. 6-20
Brake fl uid level, checking ...................... 6-19
Brake lever, front....................................... 3-6
Brake lever, rear ....................................... 3-6
Brake levers, lubricating.......................... 6-21
Brake lever free play, checking ............... 6-18
Brake pads and shoes, checking ............ 6-19
Braking ...................................................... 5-2CCables, checking and lubricating ............ 6-21
Care .......................................................... 7-1
Catalytic converters .................................. 3-9
Centerstand and sidestand, checking and
lubricating ............................................. 6-22DDimmer switch .......................................... 3-6EEngine break-in ......................................... 5-3
Engine oil and oil strainer........................ 6-10
Engine trouble warning light...................... 3-2FFinal transmission oil .............................. 6-12
Front fork, checking ................................ 6-23
Fuel ........................................................... 3-7
Fuel consumption, tips for reducing .......... 5-3
Fuel tank cap ............................................ 3-7
Fuses, replacing...................................... 6-26
HHandlebar switches................................... 3-5
Headlight bulb, replacing ........................ 6-27
High beam indicator light .......................... 3-2
Horn switch ............................................... 3-6IIdentifi cation numbers ............................... 9-1
Ignition circuit cut-off system................... 3-12
Indicator and warning lights ...................... 3-2KKeyhole cover ........................................... 3-2
Kickstarter ................................................. 3-9MMaintenance, emission control system ..... 6-3
Maintenance and lubrication, periodic ...... 6-4
Main switch/steering lock .......................... 3-1
Matte color, caution................................... 7-1
Model label................................................ 9-1
Multi-function display ................................ 3-3PPanels, removing and installing ................ 6-7
Parking ...................................................... 5-4
Part locations ............................................ 2-1RRear brake lever free play, adjusting ...... 6-18SSafe-riding points ...................................... 1-5
Safety information ..................................... 1-1
Seat......................................................... 3-10
Sidestand ................................................ 3-11
Spark plug, checking................................. 6-8
Specifi cations ............................................ 8-1
Speedometer ............................................ 3-3
Starting off................................................. 5-2Starting the engine .................................... 5-1
Start switch ............................................... 3-6
Steering, checking .................................. 6-23
Storage ..................................................... 7-4
Storage compartments............................ 3-10
TTail/brake light bulb or rear turn signal light
bulb, replacing ...................................... 6-28
Throttle grip and cable, checking and
lubricating ............................................. 6-21
Throttle grip free play, checking .............. 6-15
Tires ........................................................ 6-16
Tool kit ...................................................... 6-2
Troubleshooting ...................................... 6-29
Troubleshooting chart ............................. 6-31
Turn signal indicator light .......................... 3-2
Turn signal light bulb (front), replacing.... 6-28
Turn signal switch ..................................... 3-6VValve clearance ...................................... 6-15
Vehicle identifi cation number .................... 9-1WWheels .................................................... 6-17
Wheel bearings, checking ....................... 6-24
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