check engine YAMAHA CYGNUS L 2012 User Guide

PERIODIC MAINTENANCE AND ADJUSTMENT
6-9
6
EAU45591
Checking the spark plug The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plug can re-
veal the condition of the engine.
To remove the spark plug
1. Place the vehicle on the center-
stand.
2. Remove panel A. (See page 6-7.)
3. Remove the spark plug cap.
4. Remove the spark plug as shown,
using the spark plug wrench,
which is located in the rear storage
compartment. (See page 3-9.)
To check the spark plug
1. Check that the porcelain insulator
around the center electrode of the
spark plug is a medium-to-light tan
(the ideal color when the vehicle is
ridden normally).
TIPIf the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer check
the vehicle.2. Check the spark plug for electrode
erosion and excessive carbon or
other deposits, and replace it if
necessary.
3. Measure the spark plug gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifica-
tion.
1. Spark plug wrench
1. Spark plug wrench
1
1
Specified spark plug:
NGK/CR6HSA
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-10
6 To install the spark plug
1. Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
2. Install the spark plug with the
spark plug wrench, and then tight-
en it to the specified torque.
TIPIf a torque wrench is not available when
installing a spark plug, a good estimate
of the correct torque is 1/4–1/2 turn
past finger tight. However, the spark
plug should be tightened to the speci-
fied torque as soon as possible.3. Install the spark plug cap.
4. Install the panel.
EAU53150
Engine oil The engine oil level should be checked
before each ride. In addition, the oil
must be changed at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
To check the engine oil level
1. Place the vehicle on the center-
stand. A slight tilt to the side can
result in a false reading.
2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Wait a few minutes until the oil set-
tles, remove the engine oil filler
cap, wipe the engine oil dipstick
clean, insert it back into the oil filler
hole (without screwing it in), and
then remove it again to check the
oil level.TIPThe engine oil should be between the
minimum and maximum level marks.
1. Spark plug gapSpark plug gap:
0.6–0.7 mm (0.024–0.028 in)
Tightening torque:
Spark plug:
13 Nm (1.3 m·kgf, 9.4 ft·lbf)
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-11
64. If the engine oil is at or below the
minimum level mark, add sufficient
oil of the recommended type to
raise it to the correct level.
5. Insert the engine oil dipstick into
the oil filler hole, and then tighten
the oil filler cap.
To change the engine oil
1. Place the vehicle on the center-
stand.
2. Start the engine, warm it up for
several minutes, and then turn it
off.3. Place an oil pan under the engine
to collect the used oil.
4. Remove the engine oil filler cap,
and then remove the engine oil
drain bolt and its gasket to drain
the oil from the crankcase.
5. Install the engine oil drain bolt and
its new gasket, and then tighten
the bolt to the specified torque.
6. Refill with the specified amount of
the recommended engine oil, and
then install and tighten the engine
oil filler cap.
NOTICE
ECA11670
●
Do not use oils with a diesel
specification of “CD” or oils of a
higher quality than specified. In
addition, do not use oils labeled
“ENERGY CONSERVING II” or
higher.
●
Be sure no foreign material en-
ters the crankcase.
7. Start the engine, and then let it idle
for several minutes while checking
it for oil leakage. If oil is leaking, im-
mediately turn the engine off and
check for the cause.
8. Turn the engine off, and then
check the oil level and correct it if
necessary.
1. Engine oil filler cap
2. Engine oil dipstick
3. Maximum level mark
4. Minimum level mark
32
1
4
1. Engine oil drain bolt
2. GasketTightening torque:
Engine oil drain bolt:
20 Nm (2.0 m·kgf, 14 ft·lbf)1
2
Recommended engine oil:
See page 8-1.
Oil quantity:
1.00 L (1.06 US qt, 0.88 Imp.qt)
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-12
6
EAU20066
Final transmission oil The final transmission case must be
checked for oil leakage before each
ride. If any leakage is found, have a
Yamaha dealer check and repair the
scooter. In addition, the final transmis-
sion oil must be changed as follows at
the intervals specified in the periodic
maintenance and lubrication chart.
1. Start the engine, warm up the final
transmission oil by riding the
scooter for several minutes, and
then stop the engine.
2. Place the scooter on the center-
stand.
3. Place an oil pan under the final
transmission case to collect the
used oil.
4. Remove the final transmission oil
filler cap and its O-ring from the fi-
nal transmission case.5. Remove the final transmission oil
drain bolt and its gasket to drain
the oil from the final transmission
case.6. Install the final transmission oil
drain bolt and its new gasket, and
then tighten the bolt to the speci-
fied torque.
7. Refill with the specified amount of
the recommended final transmis-
sion oil. WARNING! Make sure
that no foreign material enters
the final transmission case.
Make sure that no oil gets on the
tire or wheel.
[EWA11311]
8. Install the final transmission oil fill-
er cap and its new O-ring, and then
tighten the oil filler cap.
9. Check the final transmission case
for oil leakage. If oil is leaking,
check for the cause.
1. Final transmission oil filler cap
2. O-ring
1. Final transmission oil drain bolt
2. Gasket
1
2
12
Tightening torque:
Final transmission oil drain bolt:
23 Nm (2.3 m·kgf, 17 ft·lbf)
Recommended final transmission
oil:
See page 8-1.
Oil quantity:
0.13 L (0.14 US qt, 0.11 Imp.qt)
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-13
6
EAU53311
Air filter and V-belt case air fil-
ter elements The air filter element should be re-
placed and the V-belt case air filter ele-
ment should be cleaned at the intervals
specified in the periodic maintenance
and lubrication chart. Service the air fil-
ter elements more frequently if you are
riding in unusually wet or dusty areas.
The air filter check hose must be fre-
quently checked and cleaned if neces-
sary.
Replacing the air filter element
1. Place the scooter on the center-
stand.
2. Remove the air filter case cover by
removing the screws.3. Pull the air filter element out.
4. Insert a new air filter element into
the air filter case. NOTICE: Make
sure that the air filter element is
properly seated in the air filter
case. The engine should neverbe operated without the air filter
element installed, otherwise the
piston(s) and/or cylinder(s) may
become excessively worn.
[ECA10481]
5. Install the air filter case cover by in-
stalling the screws.
Cleaning the air filter check hose
1. Check the hose on the rear side of
the air filter case for accumulated
dirt or water.
2. If dirt or water is visible, remove
the hose from the clamp, clean it,
and then install it.
1. Air filter case cover
2. Screw
1. Air filter element
1
2
2
1
1. Air filter check hose
2. Clamp
12
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-15
6
EAU44734
Checking the engine idling
speed Check the engine idling speed and, if
necessary, have it corrected by a
Yamaha dealer.
EAU21384
Checking the throttle grip free
play The throttle grip free play should mea-
sure 1.5–3.5 mm (0.06–0.14 in) at the
inner edge of the throttle grip. Periodi-
cally check the throttle grip free play
and, if necessary, have a Yamaha deal-
er adjust it.
EAU21401
Valve clearance The valve clearance changes with use,
resulting in improper air-fuel mixture
and/or engine noise. To prevent this
from occurring, the valve clearance
must be adjusted by a Yamaha dealer
at the intervals specified in the periodic
maintenance and lubrication chart.
Engine idling speed:
1600–1800 r/min
1. Throttle grip free play1ZAUM0051
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-21
6
EAU22721
Changing the brake fluid Have a Yamaha dealer change the
brake fluid at the intervals specified in
the TIP after the periodic maintenance
and lubrication chart. In addition, have
the oil seals of the brake master cylin-
der and caliper as well as the brake
hose replaced at the intervals listed be-
low or whenever they are damaged or
leaking.●
Oil seals: Replace every two
years.
●
Brake hose: Replace every four
years.
EAU23095
Checking and lubricating the
cables The operation of all control cables and
the condition of the cables should be
checked before each ride, and the ca-
bles and cable ends should be lubricat-
ed if necessary. If a cable is damaged
or does not move smoothly, have a
Yamaha dealer check or replace it.
WARNING! Damage to the outer
housing of cables may result in in-
ternal rusting and cause interfer-
ence with cable movement. Replace
damaged cables as soon as possi-
ble to prevent unsafe conditions.[EWA10711]EAU23114
Checking and lubricating the
throttle grip and cable The operation of the throttle grip should
be checked before each ride. In addi-
tion, the cable should be lubricated by a
Yamaha dealer at the intervals speci-
fied in the periodic maintenance chart.
The throttle cable is equipped with a
rubber cover. Make sure that the cover
is securely installed. Even though the
cover is installed correctly, it does not
completely protect the cable from water
entry. Therefore, use care not to pour
water directly onto the cover or cable
when washing the vehicle. If the cable
or cover becomes dirty, wipe clean with
a moist cloth.
Recommended lubricant:
Yamaha Chain and Cable Lube or
engine oil
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PERIODIC MAINTENANCE AND ADJUSTMENT
6-30
6
EAU25903
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 have a Yamaha dealer charge
the battery if necessary.
DryWet
Open the throttle halfway and operate
the electric starter.
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SCOOTER CARE AND STORAGE
7-4
7 2. Drain the carburetor float chamber
by loosening the drain bolt; this will
prevent fuel deposits from building
up. Pour the drained fuel into the
fuel tank.
3. Fill up the fuel tank and add fuel
stabilizer (if available) to prevent
the fuel tank from rusting and the
fuel from deteriorating.
4. Perform the following steps to pro-
tect 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.)
WARNING! To prevent dam-
age or injury from sparking,
make sure to ground thespark plug electrodes while
turning the engine over.
[EWA10951]
e. Remove the spark plug cap
from the spark plug, and then
install the spark plug and the
spark plug cap.
5. Lubricate all control cables and the
pivoting points of all levers and
pedals as well as of the side-
stand/centerstand.
6. Check and, if necessary, correct
the tire air pressure, and then lift
the scooter so that both of its
wheels are off the ground. Alterna-
tively, turn the wheels a little every
month in order to prevent the tires
from becoming degraded in one
spot.
7. Cover the muffler outlet with a
plastic bag to prevent moisture
from entering it.
8. 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 ex-
cessively 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.
TIPMake any necessary repairs before
storing the scooter.
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INDEXAAcceleration and deceleration................. 5-2
Air filter and V-belt case air filter
elements ............................................. 6-13
Auxiliary light bulb, replacing ................ 6-28BBattery................................................... 6-24
Brake fluid, changing ............................ 6-21
Brake fluid level, checking .................... 6-20
Brake lever, front..................................... 3-5
Brake lever, rear ..................................... 3-5
Brake levers, lubricating........................ 6-22
Brake pads and shoes, checking .......... 6-19
Braking .................................................... 5-2CCables, checking and lubricating .......... 6-21
Care ........................................................ 7-1
Carrier ................................................... 3-11
Catalytic converters ................................ 3-7
Centerstand and sidestand,
checking and lubricating ..................... 6-22
Cowlings and panels,
removing and installing ......................... 6-7DDimmer switch ........................................ 3-4EEngine break-in ....................................... 5-3
Engine idling speed, checking .............. 6-15
Engine oil .............................................. 6-10
Engine serial number .............................. 9-1
Engine trouble warning light.................... 3-3FFinal transmission oil ............................ 6-12
Frame serial number ............................... 9-1Front brake lever free play, checking ... 6-18
Front fork, checking .............................. 6-23
Fuel......................................................... 3-6
Fuel consumption, tips for reducing........ 5-3
Fuel gauge.............................................. 3-4
Fuel tank cap .......................................... 3-5
Fuse, replacing ..................................... 6-26
GGrab bar ............................................... 3-11HHandlebar switches ................................ 3-4
Headlight bulb, replacing ...................... 6-26
Helmet holders ....................................... 3-9
High beam indicator light ........................ 3-2
Horn switch ............................................. 3-4IIdentification numbers ............................ 9-1
Ignition circuit cut-off system ................ 3-12
Indicator lights and warning light ............ 3-2KKeyhole cover ......................................... 3-2
Kickstarter............................................... 3-8LLuggage hook ....................................... 3-11MMain switch/steering lock........................ 3-1
Maintenance and lubrication, periodic .... 6-4
Maintenance, emission control system... 6-3
Matte color, caution ................................ 7-1PParking ................................................... 5-4
Part locations .......................................... 2-1RRear brake lever free play, adjusting .... 6-18Rear turn signal light and
tail/brake light...................................... 6-28
SSafe-riding points .................................... 1-5
Safety information ................................... 1-1
Seat ......................................................... 3-8
Self-diagnosis device .............................. 3-3
Sidestand .............................................. 3-12
Spark plug, checking ............................... 6-9
Specifications .......................................... 8-1
Speedometer unit .................................... 3-3
Starting off ............................................... 5-2
Starting the engine .................................. 5-1
Start switch.............................................. 3-4
Steering, checking................................. 6-24
Storage.................................................... 7-3
Storage compartments ............................ 3-9TThrottle grip and cable,
checking and lubricating ..................... 6-21
Throttle grip free play, checking ............ 6-15
Tires ...................................................... 6-16
Troubleshooting .................................... 6-29
Troubleshooting chart ........................... 6-30
Turn signal indicator light ........................ 3-2
Turn signal light bulb (front),
replacing ............................................. 6-27
Turn signal switch ................................... 3-4VValve clearance..................................... 6-15WWheel bearings, checking ..................... 6-24
Wheels .................................................. 6-17
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