2007 YAMAHA CYGNUS 125 engine

TABLE OF CONTENTS
SAFETY INFORMATION
...................1-1
Further safe-riding points .................1-4
DESCRIPTION
...................................2-1
Left view ...........................................2-1
Right view .........................................2-2
Controls and instruments..................2-3
INSTRUMENT AND CONTROL
FUNCTIONS
........................................3-1
Main switch ......................................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 ..............................3-7
Fuel tank cap ...................................3-7
Fuel ..................................................3-8
Catalytic converter ...........................3-9
Kickstarter ........................................3-9
Seat .................................................3-9
Storage compartments ..................3-10
Sidestand .......................................3-11
Sidestand switch operation check .3-12
PRE-OPERATION CHECKS
...............4-1
Pre-operation check list ...................4-2
OPERATION 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
MINOR REPAIR
.................................. 6-1
Owner’s tool kit ................................ 6-1
Periodic maintenance and lubrication
chart ............................................. 6-3
Removing and installing panels ...... 6-6
Checking the spark plug .................. 6-7
Engine oil and oil strainer ................ 6-9
Final transmission oil ..................... 6-11
Air filter and V-belt case air filter
elements .................................... 6-12
Checking the throttle cable free
play ............................................ 6-14
Valve clearance ............................. 6-14
Tires .............................................. 6-14
Cast wheels ................................... 6-16
Adjusting the rear brake lever free
play ............................................ 6-16
Checking the front brake pads and
rear brake shoes ........................ 6-17Checking the front brake fluid
level ........................................... 6-18
Changing the brake fluid ............... 6-19
Checking and lubricating the
cables ........................................ 6-19
Checking and lubricating the throttle
grip and cable ............................ 6-20
Lubricating the front and rear brake
levers ......................................... 6-20
Checking and lubricating the
centerstand and sidestand ........ 6-20
Checking the front fork .................. 6-21
Checking the steering ................... 6-21
Checking the wheel bearings ........ 6-22
Battery ........................................... 6-22
Replacing the fuses ...................... 6-24
Replacing the headlight bulb ........ 6-25
Replacing a front turn signal light
bulb ............................................ 6-26
Replacing the tail/brake light bulb or
a rear turn signal light bulb ........ 6-27
Replacing an auxiliary light bulb ... 6-27
Troubleshooting ............................ 6-28
Troubleshooting chart ................... 6-29
SCOOTER CARE AND
STORAGE
........................................... 7-1
Matte color caution .......................... 7-1
Care ................................................ 7-1
Storage ........................................... 7-3

SAFETY INFORMATION
1-2
1

Always signal before turning or
changing lanes. Make sure that
other motorists can see you.

The posture of the operator and
passenger is important for proper
control.

The operator should keep both
hands on the handlebar and
both feet on the footboard during
operation to maintain control of
the scooter.

The passenger should always
hold onto the operator, the seat
strap or grab bar, if equipped,
with both hands and keep both
feet on the passenger footrests.

Never carry a passenger unless
he or she can firmly place both
feet on the passenger footrests.

Never ride under the influence of
alcohol or other drugs.

This scooter is designed for
on-road use only. It is not suitable
for off-road use.
Protective apparel
The majority of fatalities from scooter
accidents are the result of head inju-ries. The use of a safety helmet is the
single most critical factor in the preven-
tion or reduction of head injuries.

Always wear an approved helmet.

Wear a face shield or goggles.
Wind in your unprotected eyes
could contribute to an impairment
of vision which could delay seeing
a hazard.

The use of a jacket, substantial
shoes, trousers, gloves, etc., is ef-
fective in preventing or reducing
abrasions or lacerations.

Never wear loose-fitting clothes,
otherwise they could catch on the
control levers or wheels and cause
injury or an accident.

Never touch the engine or exhaust
system during or after operation.
They become very hot and can
cause burns. Always wear protec-
tive clothing that covers your legs,
ankles, and feet.

Passengers should also observe
the above precautions.
Modifications
Modifications made to this scooter notapproved by Yamaha, or the removal of
original equipment, may render the
scooter unsafe for use and may cause
severe personal injury. Modifications
may also make your scooter illegal to
use.
Loading and accessories
Adding accessories or cargo to your
scooter can adversely affect stability
and handling if the weight distribution of
the scooter is changed. To avoid the
possibility of an accident, use extreme
caution when adding cargo or accesso-
ries to your scooter. Use extra care
when riding a scooter that has added
cargo or accessories. Here are some
general guidelines to follow if loading
cargo or adding accessories to your
scooter:
Loading
The total weight of the operator, pas-
senger, accessories and cargo must
not exceed the maximum load limit.

Maximum load:
172 kg (379 lb)

SAFETY INFORMATION
1-3
1
When loading within this weight limit,
keep the following in mind:

Cargo and accessory weight
should be kept as low and close to
the scooter as possible. Make sure
to distribute the weight as evenly
as possible on both sides of the
scooter to minimize imbalance or
instability.

Shifting weights can create a sud-
den imbalance. Make sure that ac-
cessories and cargo are securely
attached to the scooter before
riding. Check accessory mounts
and cargo restraints frequently.

Never attach any large or heavy
items to the handlebar, front fork,
or front fender. Such items can
create unstable handling or a slow
steering response.
Accessories
Genuine Yamaha accessories have
been specifically designed for use on
this scooter. Since Yamaha cannot test
all other accessories that may be avail-
able, you must personally be responsi-
ble for the proper selection, installationand use of non-Yamaha accessories.
Use extreme caution when selecting
and installing any accessories.
Keep the following guidelines in mind,
as well as those provided under “Load-
ing” when mounting accessories.


Never install accessories or carry
cargo that would impair the perfor-
mance of your scooter. Carefully
inspect the accessory before using
it to make sure that it does not in
any way reduce ground clearance
or cornering clearance, limit sus-
pension travel, steering travel or
control operation, or obscure lights
or reflectors.

Accessories fitted to the handle-
bar or the front fork area can
create instability due to improper
weight distribution or aerody-
namic changes. If accessories
are added to the handlebar or
front fork area, they must be as
lightweight as possible and
should be kept to a minimum.

Bulky or large accessories may
seriously affect the stability of
the scooter due to aerodynamiceffects. Wind may attempt to lift
the scooter, or the scooter may
become unstable in cross
winds. These accessories may
also cause instability when
passing or being passed by
large vehicles.

Certain accessories can dis-
place the operator from his or
her normal riding position. This
improper position limits the free-
dom of movement of the opera-
tor and may limit control ability,
therefore, such accessories are
not recommended.

Use caution when adding electri-
cal accessories. If electrical acces-
sories exceed the capacity of the
scooter’s electrical system an
electric failure could result, which
could cause a dangerous loss of
lights or engine power.
Gasoline and exhaust gas

GASOLINE IS HIGHLY FLAMMA-
BLE:

Always turn the engine off when
refueling.

SAFETY INFORMATION
1-4
1

Take care not to spill any gaso-
line on the engine or exhaust
system when refueling.

Never refuel while smoking or in
the vicinity of an open flame.

Never start the engine or let it run
for any length of time in a closed
area. The exhaust fumes are poi-
sonous and may cause loss of
consciousness and death within a
short time. Always operate your
scooter in an area that has ade-
quate ventilation.

Always turn the engine off before
leaving the scooter unattended
and remove the key from the main
switch. When parking the scooter,
note the following:

The engine and exhaust system
may be hot, therefore, park the
scooter in a place where pedes-
trians or children are not likely to
touch these hot areas.

Do not park the scooter on a
slope or soft ground, otherwise it
may fall over.

Do not park the scooter near a
flammable source (e.g., a kero-sene heater, or near an open
flame), otherwise it could catch
fire.

If you should swallow any gaso-
line, inhale a lot of gasoline vapor,
or allow gasoline to get into your
eyes, see your doctor immediate-
ly. If any gasoline spills on your
skin or clothing, immediately wash
the affected area with soap and
water and change your clothes.
EAU10371
Further safe-riding points

Be sure to signal clearly when
making turns.
Left turn
Right turn

Braking can be extremely difficult
on a wet road. Avoid hard braking,
because the scooter could slide.
ZAUM00**ZAUM00**

3-1
2
34
5
6
7
8
9

INSTRUMENT AND CONTROL FUNCTIONS
EAUU0061
Main switch
The main switch controls the ignition
and lighting systems. The various main
switch positions are described below.
NOTE:

The main switch is equipped with a key-
hole cover. (See page 3-2.)
EAUT1971
ON
All electrical circuits are supplied with
power; the meter lighting, taillight, and
auxiliary lights come on, and the engine
can be started. The key cannot be re-
moved.
NOTE:

The headlight comes on automaticallywhen the engine is started and stays on
until the key is turned to “OFF” or the
sidestand is moved down.
EAU10660
OFF
All electrical systems are off. The key
can be removed.
EAU10680
LOCK
The steering is locked, and all electrical
systems are off. The key can be re-
moved.
To lock the steering
1. Turn the handlebars all the way tothe left.
2. Push the key in from the “OFF” po-
sition, and then turn it to “LOCK”
while still pushing it.
3. Remove the key.
To unlock the steering
Push the key in, and then turn it to
“OFF” while still pushing it.
WARNING

EWA10060
Never turn the key to “OFF” or
“LOCK” while the vehicle is moving,
otherwise the electrical systems will
be switched off, which may result in
loss of control or an accident. Make
ZAUM00**

1. Push.
ZAUM00**
1

1. Turn.
2. Release.
12
ZAUM00**

INSTRUMENT AND CONTROL FUNCTIONS
3-2
1
2
3
4
5
6
7
8
9sure that the vehicle is stopped be-
fore turning the key to “OFF” or

“LOCK”.
EAUT2111
Keyhole cover
To open the keyhole cover
Insert the key bow into the keyhole cov-
er receptacle as shown, and then turn
the key to the right to open the cover.
To close the keyhole cover
Push the keyhole cover lever inward
and the keyhole cover will close.

EAU11003
Indicator and warning lights
EAU11020
Turn signal indicator light “”
This indicator light flashes when the
turn signal switch is pushed to the left or
right.
EAU11080
High beam indicator light “”
This indicator light comes on when the
high beam of the headlight is switched
on.
1. Keyhole cover lever
ZAUM00**
1

1. High beam indicator light “ ”
2. Turn signal indicator light “ ”
3. Engine trouble warning light “ ”
ZAUM00**
RESET
SELECT
1
2
3

INSTRUMENT AND CONTROL FUNCTIONS
3-3
2
34
5
6
7
8
9

EAUT1930
Engine trouble warning light “”
This warning light flashes when an
electrical circuit monitoring the engine
is defective. When this occurs, have a
Yamaha dealer check the self-diagno-
sis system.
The electrical circuit of the warning light
can be checked by turning the key to
“ON”. If the warning light does not come
on for a few seconds, then go off, have
a Yamaha dealer check the electrical
circuit.
EAU11601
Speedometer
The speedometer shows the riding
speed.
When the key is turned to “ON”, the
speedometer needle will sweep once
across the speed range and then return
to zero in order to test the electrical cir-
cuit.
EAUT1952
Multi-function display
WARNING

EWA14430
Be sure to stop the vehicle before
making any setting changes to the
multi-function display.
The multi-function display is equipped
with the following:

an odometer (which shows the to-
tal distance traveled)
1. Speedometer
ZAUM00**
RESET
SELECT
1
1. Tripmeter
2. Oil change indicator “ ”
3. Odometer
4. Fuel meter
5. “RESET” button
6. “SELECT” button
7. Clock
ZAUM00**
RESET
SELECT
1
2
3
4
5
6
7

INSTRUMENT AND CONTROL FUNCTIONS
3-4
1
2
3
4
5
6
7
8
9


a tripmeter (which shows the dis-
tance traveled since it was last set
to zero)

an oil change tripmeter (which
shows the distance traveled since
the last engine oil change)

an oil change indicator (which
flashes when the engine oil should
be changed)

a clock

a fuel meter
NOTE:


When the key is turned to “ON”, all
segments of the display come on
for a few seconds. During this
time, the multi-function display is
performing a self-test.

Be sure to turn the key to “ON” be-
fore using the “SELECT” and “RE-
SET” buttons.
Odometer, tripmeter and oil change
tripmeter modes
Pushing the “SELECT” button switches
the display among the odometer mode
“ODO”, the tripmeter mode “TRIP” and
the oil change tripmeter “OIL CHANGE
TRIP” in the following order:ODO
→
TRIP
→
OIL CHANGE TRIP
→
ODO
Odometer
NOTE:

If the odometer indicates “-----”, have a
Yamaha dealer check the multi-func-
tion display, as it may be faulty.
Tripmeter
To reset the tripmeter, select it by push-
ing the “SELECT” button until “TRIP” is
displayed, and then push the “RESET”
button at least 1 second.
NOTE:

If the tripmeter indicates “-----”, have a
Yamaha dealer check the multi-func-
tion display, as it may be faulty.
Oil change tripmeter
To reset the oil change tripmeter, select
it by pushing the “SELECT” button until
“OIL CHANGE TRIP” is displayed, and
then push the “RESET” button at least
3 seconds. After resetting the oil
change tripmeter, “ODO” will be dis-
played.
NOTE:

If the “SELECT” button is pushed again
or the “SELECT” button hasn’t been
pushed within 10 seconds, the oil
change tripmeter will keep counting
and “ODO” will be displayed.
Oil change indicator
Oil change indicator “”
This indicator flashes at the initial 1000
km (600 mi), then at every 3000 km
(1800 mi) thereafter to indicate that the
engine oil should be changed.
After changing the engine oil, reset the
oil change tripmeter.
If the engine oil is changed before the
oil change indicator flashes (i.e. before
the periodic oil change interval has
been reached), the oil change tripmeter
must be reset after the oil change for
the next periodic oil change to be indi-
cated at the correct time.
NOTE:


If the oil change tripmeter is reset
before the initial 1000 km (600 mi),
the next periodic oil change inter-