check engine YAMAHA CYGNUS 125 2000 User Guide

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PERIODIC MAINTENANCE AND MINOR REPAIR
EAU21400
Adjusting the valve clearanceThe 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 in-
tervals specified in the periodic mainte-
nance and lubrication chart.
EAU21370
Adjusting the throttle cable
free playThe throttle cable free play should mea-
sure 3~5 mm (0.12~0.20 in) at the
throttle grip. Periodically check the
throttle cable free play and, if necessary,
adjust it as follows.NOTE:
The engine idling speed must be cor-
rectly adjusted before checking and ad-
justing the throttle cable free play.1. Loosen the locknut.
2. To increase the throttle cable free
play, turn the adjusting nut in direc-
tion (a). To decrease the throttle
cable free play, turn the adjusting
nut in direction (b).
ZAUM00**
1
2
(a)
(b)
1. Locknut
1. Adjusting nut3. Tighten the locknut.
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PERIODIC MAINTENANCE AND MINOR REPAIR8As the brake pads wear, it is nor-
mal for the brake fluid level to
gradually go down. However, if the
brake fluid level goes down sud-
denly, have a Yamaha dealer check
the cause.
EAU22720
Changing the brake fluidHave a Yamaha dealer change the brake
fluid at the intervals specified in the
NOTE 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 below or
whenever they are damaged or leaking.
8Oil seals: Replace every two years.
8Brake hose: Replace every four
years.
EAU23100
Checking and lubricating the
cablesThe operation of all control cables and
the condition of the cables should be
checked before each ride, and the
cables and cable ends should be lubri-
cated if necessary. If a cable is dam-
aged or does not move smoothly, have
a Yamaha dealer check or replace it.
Recommended lubricant:
Engine oil
EWA10720
wDamage to the outer sheath may in-
terfere with proper cable operation
and will cause the inner cable to rust.
Replace a damaged cable as soon as
possible to prevent unsafe condi-
tions.
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PERIODIC MAINTENANCE AND MINOR REPAIR
EAU23271
Checking the front forkThe condition and operation of the front
fork must be checked as follows at the
intervals specified in the periodic main-
tenance and lubrication chart.
To check the condition
EWA10750
wSecurely support the motorcycle so
that there is no danger of it falling
over.Check the inner tubes for scratches,
damage and excessive oil leakage.
To check the operation
1. Place the motorcycle on a level sur-
face and hold it in an upright posi-
tion.
2. While applying the front brake, push
down hard on the handlebars sev-
eral times to check if the front fork
compresses and rebounds
smoothly.
ZAUM00**
ECA10590
cCIf any damage is found or the front
fork does not operate smoothly, have
a Yamaha dealer check or repair it.
EAU23280
Checking the steeringWorn or loose steering bearings may
cause danger. Therefore, the operation
of the steering must be checked as fol-
lows at the intervals specified in the
periodic maintenance and lubrication
chart.
1. Place a stand under the engine to
raise the front wheel off the ground.
EWA10750
wSecurely support the motorcycle so
that there is no danger of it falling
over.2. Hold the lower ends of the front fork
legs and try to move them forward
and backward. If any free play can
be felt, have a Yamaha dealer check
or repair the steering.
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PERIODIC MAINTENANCE AND MINOR REPAIR
EAU25901
Troubleshooting chart
EWA10840
wKeep away open flames and do not smoke while checking or working on the fuel system.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 charge the battery if necessary.
DryWet
Open the throttle halfway and operate
the electric starter.
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SCOOTER CARE AND STORAGE
EWA10950
wTo prevent damage or injury from
sparking, make sure to ground the
spark plug electrodes while turning
the engine over.5. Lubricate all control cables and the
pivoting points of all levers and
pedals as well as of the sidestand/
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 plas-
tic bag to prevent moisture from en-
tering 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 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 6-23.
NOTE:
Make any necessary repairs before stor-
ing the scooter.
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INDEXAAcceleration and deceleration.................. 5-2
Air filter and V-belt case air filter
elements................................................6-11BBattery.....................................................6-23
Brake fluid level, checking ......................6-19
Brake fluid, changing ..............................6-20
Brake lever, front ...................................... 3-4
Brake lever, rear....................................... 3-4
Brake levers, lubricating.........................6-21
Brake pads and shoes, checking..........6-18
Braking...................................................... 5-2CCables, checking and lubricating ...........6-20
Carburetor,adjusting...............................6-13
Catalytic converter................................... 3-6
Centerstand and sidestand, checking and lu-
bricating.................................................6-21DDimmer switch.......................................... 3-4EEngine break-in ......................................... 5-3
Engine oil and oil strainer .......................... 6-8FFinal transmission oil ..............................6-10
Front brake lever free play, checking....6-17
Fuel........................................................... 3-6
Fuel consumption, tips for reducing ......... 5-3
Fuel gauge ................................................ 3-3
Fuel tank cap ............................................ 3-5
Fuses, replacing.....................................6-25
HHandlebar switches.................................. 3-3
Headlight bulb, replacing........................6-26
Helmet holder............................................ 3-8
High beam indicator light .......................... 3-2
Horn switch............................................... 3-4IIdentification numbers.............................. 9-1
Indicator lights........................................... 3-2KKey identification number......................... 9-1
Kickstarter................................................ 3-7LLuggage hook........................................... 3-9MMain switch/steering lock......................... 3-1
Model label................................................ 9-2PPanels, removing and installing................ 6-6
Parking...................................................... 5-4
Part locations............................................ 2-1
Periodic maintenance and lubrication
chart ........................................................ 6-3
Pre-operation check list........................... 4-2
Rear brake lever free play, adjusting .....6-18SSafe-riding points...................................... 1-4
Safety information..................................... 1-1
Seat ........................................................... 3-7
Sidestand................................................3-10
Sidestand switch operation check .........3-10Spark plug, checking................................ 6-7
Specifications............................................ 8-1
Speedometer unit..................................... 3-3
Start switch............................................... 3-4
Starting a cold engine ............................... 5-1
Starting off ................................................. 5-2
Storage...................................................... 7-3
Storage compartment............................... 3-8
TTail/brake light bulb, replacing ................6-27
Throttle cable free play, adjusting..........6-14
Throttle grip and cable, checking and lubricat-
ing ..........................................................6-21
Tires........................................................6-15
Tool kit ....................................................... 6-1
Troubleshooting......................................6-29
Troubleshooting chart.............................6-30
Turn signal indicator light.......................... 3-2
Turn signal light bulb (front), replacing ...6-28
Turn signal switch ..................................... 3-4VValve clearance, adjusting ......................6-14
Vehicle identification number .................... 9-1WWheel bearings, checking ......................6-23
Wheels....................................................6-17
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