2006 YAMAHA CYGNUS 125 engine

CAUTION:

Before installing the drain plug,
make sure that the O-ring, springand filter screen is in position.Locking torque of drain bolt: 2.0kg.m
Locking torque of drain plug: 3.2kg.m4.Clean the filter screen.
5.Inspect the O-ring for damages, re-
place if necessary.
6.Tight the drain bolt and drain plug
according to the torque specification.Oil replaced periodicallyOil replaced periodically
(including the oil needed
for replacing filter element)Special engine oil used
for four-stroke motor-
cycleYAHAMA Four-stroke
YAMALUBE engine oil,
SAE 10W-30 combus-
tion engine oil (API) ,
Spec. SF1.0L
1.2LMAINTENANCE
CAUTION:

When re-fueling, make sure that no
foreign materials fall into the oil
tank.
7.Re-install the engine oil cap.
8.Start the engine, warm the vehicle
for a few minutes, and check for
leakage. While the engine oil leaking,
shut off the engine and inspect the
parts leaking.
9.Shut off the engine, check the oil
level. Re-install the oil cap.
7-4

Make sure that no foreign material
falls into gear box when refueling
or discharging gear oil. Prevent the
gear oil from adhering to the tyre.
4.Reinstall the refuel plug and check
the leakage of gear oil.
3.Reinstall the air filter cover and tight
the screws to prevent the un-filtered
air flowing into the engine.
MAINTENANCE
■ ■■ ■
■Gear oil1.Park the vehicle on a flat place, re-
move refuel plug and drain bolt to dis-
charge the gear oil.
2.Tight the drain bolt to 2.3kgm.
3.Refuel gear oil.Total capacity of gear oilWhile exchanging
Gear oil type150cc
130cc
YAHAMA special gear oil
YAHAMA special four-stroke engine oil
■ ■■ ■
■Air filter1.Loose the screws and remove the air
filter cover.
2.Take out the filter element, clean or
replace if necessary.
WARNING
7-5
refuel plug
drain bolt

■ ■■ ■
■Adjust mixing ratio1.Open the rubber cover which locates
under seat. 1. Remove the crankcase cover.
2. Take out the filter to clean.
■ ■■ ■
■Crankcase filterMAINTENANCE
WARNING

Use the specified solvent to clean
the parts, never use petrol or sol-
vent with low flash point which willcause fire or explosion.CAUTION:

Do not twist the filter element toavoid of damages.
3. Apply suitable engine oil (SAE 10W-
30) to the filter element after drying.
4.Install the filter element, crankcase
cover and kick-starter back.CAUTION:

To avoid fast wearing of the parts
in belt chamber, you should main-
tain the filter element in the belt
chamber as per time and mileagelisted in the Consumer Manual.2.Adjust the screw.
NOTE:
The mixing ratio pre-set should beoperated by local agency.
7-6
mixing ratio
adjustment
screw

CAUTION:

Before the motorcycle leaving factory,
we have already set the carburetor to
the standard position. Change the set-
ting at random will affect the engine
performance and increase the dis-charge of exhaust gas.■ ■■ ■
■Adjust throttle gripNOTE: Adjust idle speed before adjusting thefree gap of throttle grip.
1.Loose the fixing nut.
2.Turn the adjustor till the clearance
meets specification.
3.Fasten the fixing nut and recheck
the clearance whether meets the stan-
dard clearance. idle speed
adjusting
screw
MAINTENANCE
■ ■■ ■
■Adjust idle speedNOTE: Warm the engine before adjusting theidle speed.
1.Remove the small lid which locates
under the seat.
2.Turn the idle speed adjusting screw.
Turn clockwiseTurn counter-
clockwise
Idle speed
specificationSpeed up
Speed down
1700rpm 50rpm
Clearance: 0.7mm - 0.8mm
Model: C7ER
Clearance specified: 3 - 5mm
Adjusting direction of throttle grip clearance1. Remove the ignition plug to check
the clearance and model.■ ■■ ■
■Check ignition plug
7-7
vehicle idling adjustment
position3-5mm

MAINTENANCE
■ ■■ ■
■Check front forkThe motorcycle shall be securely
supported when being checked, so
that it would not fall over.1.Visual examination
Check the inner tubes for scratches,
damages or oil leakage.
2.Action examination
Pull the motorcycle to a flat place.
a.Hold the handlebar and keep the
motorcycle upright, grasp the front and
rear brake lever to avoid slipping when
checking.
b.Actuate the handlebar up and right
for several times to check the action
of front fork.
CAUTION:

If you find any damage, oil leakage
or malfunction, ask your agency tocheck it.■ ■■ ■
■Check steering systemWorn or loose steering bearings may
cause danger. Place a stand under the
engine to raise the front wheel off
ground. Hold the lower ends of the
front fork and move them forward and
backward. If any free play can be felt,
ask your agency to check it.
WARNING

Make sure that the motorcycle
stands steadily when checking thesteering system to avoid hazard.Fuse specification: 15A
■ ■■ ■
■Replace fuse1.Remove the cover of accumulator.
2.Remove the negative terminal (-) and
positive terminal (+), then you can
take out the fuse.
3.Replace the blown fuse.CAUTION:

Do not use fuses of a higher amper-
age rating than recommended to
avoid extensive damages to the elec-
trical system, which may result infire.
WARNING
7-9

TROUBLE SHOOTING
1 Engine cannot start8-1
2 Shut-down suddenly while running8-1
3 Lights failure8-1

TROUBLE SHOOTING■ ■■ ■
■Engine cannot start1.Whether the main switch locates on
position ON?
2.Is fuel enough? Whether the needle
points within the fuel range (above E
line)?
3.While pressing start switch, do you
hold rear brake lever?
4.While pressing start switch, do you
turn throttle grip? (See references listed
in page 10)
If you have already confirmed the 1-4
procedures, and the motorcycle still
cannot start:
5.Locate the main switch on position
ON, press horn switch, the horn does
not operate means there is possible
fuse failure.
6.If the fuse is good, use kick-starter
to start the engine and seek help from
your agency.
8-1
■ ■■ ■
■Shut-down suddenly while
runningCheck the oil level.
Refuel as soon as possible if the fuel
is not enough.■ ■■ ■
■Lights failureCheck as per following:
1.Whether the main switch locates on
position ON?
2.After starting the engine, check
whether the front headlight and rear
light is on?
3.Can the switches operate well?
4.Press horn switch, does the horn
operate?
The horn operates well means bulb
failure; the horn does not operate
means that there is possible fuse
failure.
The troubles other than listed
above or if you have any
questions, please consult your
agency.

SPECIFICATIONDimension and weightOverall length
Overall width
Overall height
Maximum load
Wheel baseMinimum ground clearanceBasic weight
1,860mm
670mm
1,045mm
153 ± 7kg
1,250mm ± 30mm
95mm ± 20mm
105kg ± 7kg4-stroke SOHC
Single cylinder, Forward inclined
125cc
51.5mm
× 60mm
9.5:1
electrical/kick-start
Forced lubrication
1.2L
■ ■■ ■
■Specification
Item Specification
Item Specification
Engine
ModelCylinder arrangementAir displacement
Bore x Stroke
Compression ratio
Starting system
LubricationE/G lubrication oil capacity
Electrical devices
Ignition spark modelAccumulator capacityAccumulator modelTransmission devicePrimary reductionReduction ratio(idem)Second reductionReduction ratio(idem)ClutchHelical gear
40/15
Spur gear
38/13
Dry, centrifugal
C7ER
12V, 6AH
GTX7A-BS/YTX7A-BS
Variable speed ratio
Model
Shift type
Variable speed ratioV-belt infinite variable speed
Infinite variable speed
0.852 - 2.572 FuelTank capacity
5.4L
9-1