2005 YAMAHA CYGNUS 125 service

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Q QQ Q
Q SAFETY INFORMATION
EAU10260
SCOOTERS ARE SINGLE TRACK VE-
HICLES. THEIR SAFE USE AND OP-
ERATION ARE DEPENDENT UPON
THE USE OF PROPER RIDING TECH-
NIQUES AS WELL AS THE EXPER-
TISE OF THE OPERATOR. EVERY OP-
ERATOR SHOULD KNOW THE FOL-
LOWING REQUIREMENTS BEFORE
RIDING THIS SCOOTER.
HE OR SHE SHOULD:
8OBTAIN THOROUGH INSTRUC-
TIONS FROM A COMPETENT
SOURCE ON ALL ASPECTS OF
SCOOTER OPERATION.
8OBSERVE THE WARNINGS AND
MAINTENANCE REQUIRE-
MENTS IN THE OWNER’S
MANUAL.
8OBTAIN QUALIFIED TRAINING IN
SAFE AND PROPER RIDING
TECHNIQUES.
8OBTAIN PROFESSIONAL TECH-
NICAL SERVICE AS INDICATED
BY THE OWNER’S MANUAL AND/
OR WHEN MADE NECESSARY
BY MECHANICAL CONDITIONS.Safe riding
8Always make pre-operation checks.
Careful checks may help prevent
an accident.
8This scooter is designed to carry
the operator and passenger.
8The failure of motorists to detect
and recognize scooters in traffic is
the predominating cause of auto-
mobile/scooter accidents. Many
accidents have been caused by an
automobile driver who did not see
the scooter. Making yourself con-
spicuous appears to be very effec-
tive in reducing the chance of this
type of accident.
Therefore:
9Wear a brightly colored jacket.
9Use extra caution when
approaching and passing
through intersections, since
intersections are the most
likely places for scooter
accidents to occur.
9Ride where other motorists can
see you. Avoid riding in another
motorist’s blind spot.8Many accidents involve inexperi-
enced operators. In fact, many op-
erators who have been involved in
accidents do not even have a cur-
rent driver’s license.
9Make sure that you are quali-
fied and that you only lend your
scooter to other qualified
operators.
9Know your skills and limits.
Staying within your limits may
help you to avoid an accident.
9We recommend that you
practice riding your scooter
where there is no traffic until
you have become thoroughly
familiar with the scooter and all
of its controls.
Many accidents have been caused
by error of the scooter operator. A
typical error made by the operator
is veering wide on a turn due to
EXCESSIVE SPEED or
undercornering (insufficient lean
angle for the speed).
9Always obey the speed limit
and never travel faster than
warranted by road and traffic
conditions.
EAU10220
Q QQ Q
Q SAFETY INFORMATION
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PERIODIC MAINTENANCE AND MINOR REPAIR
EAU17224
PERIODIC MAINTENANCE AND MINOR REPAIR
EAU17280
Safety is an obligation of the owner.
Periodic inspection, adjustment and lu-
brication will keep your vehicle in the
safest and most efficient condition pos-
sible. The most important points of in-
spection, adjustment, and lubrication are
explained on the following pages.
The intervals given in the periodic main-
tenance and lubrication chart should be
simply considered as a general guide
under normal riding conditions. However,
DEPENDING ON THE WEATHER, TER-
RAIN, GEOGRAPHICAL LOCATION,
AND INDIVIDUAL USE, THE MAINTE-
NANCE INTERVALS MAY NEED TO BE
SHORTENED.
EWA10320
wIf you are not familiar with mainte-
nance work, have a Yamaha dealer do
it for you.
EWA10330
wThis scooter is designed for use on
paved roads only. If this scooter is
operated in abnormally dusty, muddy
or wet conditions, the air filter ele-
ment should be cleaned or replaced
more frequently, otherwise rapid en-
gine wear may result. Consult a
Yamaha dealer for proper mainte-
nance intervals.
EAU17520
Owner’s tool kitZAUM00**
1
1. Owner’s tool kitThe owner’s tool kit is located inside the
storage compartment under the seat.
(See page 3-7.)
The service information included in this
manual and the tools provided in the
owner’s tool kit are intended to assist
you in the performance of preventive
maintenance and minor repairs. How-
ever, additional tools such as a torque
wrench may be necessary to perform
certain maintenance work correctly.
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PERIODIC MAINTENANCE AND MINOR REPAIR
EAU18660
NOTE:
8The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
8Hydraulic brake service
9Regularly check and, if necessary, correct the brake fluid level.
9Every two years replace the internal components of the brake master cylinder and caliper, and change the brake
fluid.
9Replace the brake hoses every four years and if cracked or damaged.24 Moving parts and cables Lubricate.———— —
25
*Throttle grip housing
and cable Check operation and free play.
 Adjust the throttle cable free play if necessary.
 Lubricate the throttle grip housing and cable.———— —
26*Air induction system Check the air cut-off valve, reed valve, and hose for
damage.
 Replace the entire air induction system if necessary.———— —
27*Lights, signals and
switches Check operation.
 Adjust headlight beam.————— — NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (u1,000 km)
ANNUAL
CHECK
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PERIODIC MAINTENANCE AND MINOR REPAIR
EAU25860
TroubleshootingAlthough Yamaha scooters receive a
thorough inspection before shipment
from the factory, trouble may occur dur-
ing operation. Any problem in the fuel,
compression, or ignition systems, for
example, can cause poor starting and
loss of power.
The following troubleshooting chart rep-
resents a quick and easy procedure for
checking these vital systems yourself.
However, should your scooter require any
repair, take it to a Yamaha dealer, whose
skilled technicians have the necessary
tools, experience, and know-how to ser-
vice the scooter properly.
Use only genuine Yamaha replacement
parts. Imitation parts may look like
Yamaha parts, but they are often infe-
rior, have a shorter service life and can
lead to expensive repair bills.
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SPECIFICATIONS
-20˚ -10˚ 0˚ 10˚ 20˚ 30˚ 40˚ 50˚
SAE 10W-30SAE 10W-40
SAE 20W-40SAE 20W-50
ZAUM00**
EAU26320
SPECIFICATIONS
EAU26339
DimensionsOverall length
1855 mm
Overall width
685 mm
Overall height
1110 mm
Seat height
770 mm
Wheelbase
1295 mm
Ground clearance
110 mm
Minimum turning radius
1900 mmWeightWith oil and fuel
121.0 kgEngineEngine type
Forced air cooled 4-stroke, SOHC
Cylinder arrangement
Forward-inclined single cylinder
Displacement
124.0 cm
3
Bore & stroke
52.4 x 57.9 mm
Compression ratio
10.00 :1
Starting system
Electric starter and kickstarter
Lubrication system
Wet sump
Engine oilType
SAE20W40
Recommended engine oil grade
API service SE, SF, SG type or higher
Engine oil quantity
Periodic oil change
0.90 L
Without oil filter element removal
0.90 LFinal transmission oilType
SAE10W30 type SE motor oil
Quantity
0.13 LAir filterAir filter element
Oil-coated paper elementFuelRecommended fuel
Regular unleaded gasoline only
Fuel tank capacity
7.1 L
CarburetorManufacturer
Taiwan KEI HIN
Type x quantity
CVK24 x 1Spark plug(s)Manufacturer/model
NGK / CR7E
Spark plug gap
0.6-0.7 mmClutchClutch type
Dry, centrifugal automaticTransmissionPrimary reduction system
Helical gear
Primary reduction ratio
38/13 (2.923)
Secondary reduction system
Helical gear
Secondary reduction ratio
40 / 12 (3.333)
Transmission type
V-belt automatic
Operation
Centrifugal automatic typeChassisFrame type
Steel tube underbone
Caster angle
27.00 degree
Trail
90.0 mm
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