check engine YAMAHA SR125 2000 Owners Manual

EAU00009
TABLE OF CONTENTS
GIVE SAFETY THE RIGHT OF WAY ..................1-1
DESCRIPTION ....................................................2-1
Left view ............................................................. 2-1
Right view...........................................................2-2
Controls/Instruments ..........................................2-3
INSTRUMENT AND CONTROL FUNCTIONS ....3-1
Main switch/steering lock ................................... 3-1
Indicator lights ....................................................3-2
Speedometer......................................................3-2
Handlebar switches ............................................3-2
Clutch lever ........................................................3-4
Shift pedal ..........................................................3-4
Front brake lever ................................................ 3-4
Rear brake pedal................................................ 3-5
Fuel tank cap......................................................3-5
Fuel ....................................................................3-6
Fuel cock ............................................................3-6
Starter (choke) knob...........................................3-7
Seat ....................................................................3-8
Helmet holder .....................................................3-8
Rear shock absorber adjustment .......................3-9
Sidestand ...........................................................3-9
Sidestand/clutch switch operation check ......... 3-10PRE-OPERATION CHECKS ...............................4-1
Pre-operation check list......................................4-1
OPERATION AND IMPORTANT RIDING
POINTS................................................................5-1
Starting the engine .............................................5-1
Starting a warm engine ......................................5-3
Shifting ...............................................................5-4
Recommended shift points
(for Switzerland only) ......................................5-4
Tips for reducing fuel consumption ....................5-5
Engine break-in ..................................................5-5
Parking ...............................................................5-6
PERIODIC MAINTENANCE AND MINOR
REPAIR................................................................6-1
Tool kit................................................................6-1
Periodic maintenance and lubrication chart .......6-2
Panel removal and installation ...........................6-5
Panels A and B ..................................................6-5
Spark plug ..........................................................6-6
Engine oil ...........................................................6-8
Air filter .............................................................6-10
Carburetor adjustment .....................................6-11
Idle speed adjustment ......................................6-11
123
456
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INSTRUMENT AND CONTROL FUNCTIONS
3-10
3
EAU00332
Sidestand/clutch switch
operation checkCheck the operation of the sidestand
switch and clutch switch against the in-
formation below.
EW000046
WARNING
@ l
Be sure to use the centerstand
during this inspection.
l
If improper operation is noted,
consult a Yamaha dealer.
@CD-08E
CD-08E
TURN MAIN SWITCH TO “ON” AND
THE ENGINE STOP SWITCH TO “ ”.TRANSMISSION IS IN GEAR AND
SIDESTAND IS UP.PULL IN CLUTCH LEVER AND
PUSH START SWITCH.ENGINE WILL START.
SIDESTAND IS DOWN.ENGINE WILL STALL.SIDESTAND SWITCH IS OK.CLUTCH SWITCH IS OK.
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4-1
4
EAU01114
4-PRE-OPERATION CHECKS
Owners are personally responsible for their vehicle’s condition. Your motorcycle’s vital functions can start to deteriorate
quickly and unexpectedly, even if it remains unused (for instance, if it is exposed to the elements). Any damage, fluid leak or
loss of tire pressure could have serious consequences. Therefore, it is very important that, in addition to a thorough visual in-
spection, you check the following points before each ride.
EAU00340
PRE-OPERATION CHECK LIST
ITEM CHECKS PAGE
Front brake• Check operation, free play, fluid level and fluid leakage.
• Fill with DOT 4 (or DOT 3) brake fluid if necessary.
6-16 ~ 6-20
Rear brake• Check operation, condition and free play.
• Adjust if necessary.
Clutch• Check operation, condition and free play.
• Adjust if necessary.6-16
Throttle grip and housing• Check for smooth operation.
• Lubricate if necessary.6-23
Engine oil• Check oil level.
• Fill with oil if necessary.6-8 ~ 6-9
Drive chain• Check chain slack and condition.
• Adjust if necessary.6-21 ~ 6-23
Wheels and tires• Check tire pressure, wear, damage and spoke tightness.
• Tighten spokes if necessary.6-13 ~ 6-15, 6-30 ~ 6-33
Control and meter cables• Check for smooth operation.
• Lubricate if necessary.6-23
Brake and shift pedal
shafts• Check for smooth operation.
• Lubricate if necessary.6-24
Brake and clutch lever
pivots• Check for smooth operation.
• Lubricate if necessary.6-24
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5-1
5
EAU00372
5-OPERATION AND IMPORTANT RIDING POINTS
EAU00373
WARNING
@ l
Before riding this motorcycle,
become thoroughly familiar
with all operating controls and
their functions. Consult a
Yamaha dealer regarding any
control or function that you do
not thoroughly understand.
l
Never start your engine or let it
run for any length of time in a
closed area. The exhaust fumes
are poisonous and can cause
loss of consciousness and
death within a short time. Al-
ways operate your motorcycle
in an area with adequate ventila-
tion.
l
Before starting out, always be
sure the sidestand is up. Failure
to retract the sidestand com-
pletely can result in a serious
accident when you try to turn a
corner.
@
EAU03011
Starting the engineNOTE:@ This motorcycle is equipped with an ig-
nition circuit cut-off system. The engine
can be started only under one of the
following conditions:l
The transmission is in neutral.
l
The sidestand is up, the transmis-
sion is in gear and the clutch is dis-
engaged.
The motorcycle must not be ridden
when the sidestand is down.
@
EW000054
WARNING
@ Before going through the following
steps, check the function of the sid-
estand switch and clutch switch.
(Refer to page 3-10.) @
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-3
6
10
*Wheels• Check runout, spoke tightness and for damage.
• Tighten spokes if necessary.ÖÖÖÖ
11*Tires• Check tread depth and for damage.
• Replace if necessary.
• Check air pressure.
• Correct if necessary.ÖÖÖÖ
12*Wheel bearings• Check bearing for looseness or damage.ÖÖÖÖ
13*Swingarm• Check operation and for excessive play.ÖÖÖÖ
14 Drive chain• Check chain slack.
• Make sure that the rear wheel is properly aligned.
• Clean and lubricate.Every 1,000 km and after washing
the motorcycle or riding in the rain.
15*Steering bearings• Check bearing play and steering for roughness.ÖÖÖÖÖ
• Lubricate with lithium-soap-based grease. Every 24,000 km
16*Chassis fasteners• Make sure that all nuts, bolts and screws are properly tightened.ÖÖÖÖ Ö
17 Sidestand, centerstand• Check operation.
• Lubricate.ÖÖÖÖ Ö
18*Sidestand switch• Check operation.ÖÖÖÖÖ Ö
19*Front fork• Check operation and for oil leakage.ÖÖÖÖ
20*Shock absorber
assemblies• Check operation and shock absorbers for oil leakage.ÖÖÖÖ
21*Carburetor• Check starter (choke) operation.
• Adjust engine idling speed.ÖÖÖÖÖ Ö
22 Engine oil• Change.ÖÖÖÖÖ Ö
23 Engine oil filter element•Clean.ÖÖÖ
24*Front and rear brake
switches• Check operation.ÖÖÖÖÖ Ö
25 Moving parts and cables• Lubricate.ÖÖÖÖ Ö NO. ITEM CHECK OR MAINTENANCE JOBODOMETER READING (´1,000 km)
ANNUAL
CHECK
1 6 12 18 24
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-8
6
EAU01093*
Engine oilOil level inspection
1. Place the motorcycle on the cen-
terstand. Warm up the engine for
several minutes.NOTE:@ Be sure the motorcycle is positioned
straight up when checking the oil level.
A slight tilt toward the side can result in
false readings. @
2. With the engine stopped, check
the oil level through the level win-
dow located at the lower part of
the right side crankcase cover.NOTE:@ Wait a few minutes until the oil level
settles before checking. @3. The oil level should be between
the maximum level and minimum
level marks. If the level is low, fill
the engine with sufficient oil to
raise it to the specified level.Engine oil replacement and oil filter
element cleaning
1. Warm up the engine for a few min-
utes.
2. Stop the engine. Place an oil pan
under the engine and remove the
oil filler cap.
3. Remove the drain bolt and drain
the oil.
EC000070*
CAUTION:@ When removing the oil drain bolt,
the O-ring, compression spring, and
oil strainer will fall out. Take care not
to lose these parts. @
1. Oil level window
2. Maximum level mark
3. Minimum level mark
1. Engine oil drain bolt A
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-9
6 4. Remove the filter cover screws,
drain bolt and the oil filter cover
and oil filter.
5. Clean the oil filter and strainer with
solvent. Replace if necessary.
6. Check the O-rings. If damaged, re-
place it.
7. Install the drain bolt, filter cover
screws and drain bolt. Then tight-
en to the specified torque.
NOTE:@ Make sure the O-ring is seated proper-
ly. @
EC000071*
CAUTION:@ Before reinstalling the oil drain bolt,
do not forget to install the O-ring,
compression spring, and oil strainer
in position. @8. Fill engine with oil. Install the oil fill-
er cap and tighten.
EC000066
CAUTION:@ l
Do not put in any chemical addi-
tives. Engine oil also lubricates
the clutch and additives could
cause clutch slippage.
l
Be sure no foreign material en-
ters the crankcase.
@9. Start the engine and warm up for a
few minutes. While warming up,
check for oil leakage. If oil leakage
is found, stop the engine immedi-
ately and check for the cause.
10. Stop the engine and check the oil
level.
1. Filter cover screw (´ 2)
2. Engine oil drain bolt B
Tightening torque:
Drain bolt A:
43 Nm (4.3 m·kg)
Filter cover screw:
7 Nm (0.7 m·kg)
Drain bolt B:
10 Nm (1.0 m·kg)
Recommended oil:
See page 8-1.
Oil quantity:
Total amount:
1.3 L
Periodic oil change:
1.0 L
With oil filter replacement:
1.1 L
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-12
6
EAU00634
Throttle cable free play
adjustmentNOTE:@ Before checking the throttle cable free
play, the engine idling speed should be
adjusted. @Adjust the throttle cable by turning the
adjusting nut so that specified free play
at the throttle grip is obtained.1. Loosen the locknut.
2. Turn the adjusting nut in
direction
a to increase free play
and in direction
b to decrease
free play.
3. Tighten the locknut.
EAU00636
Cam chain adjustmentThe cam chain becomes loose with
use, resulting in improper valve timing
and engine noise. To prevent this, the
cam chain tensioner must be adjusted
regularly. This adjustment, however,
should be left to a professional
Yamaha service technician.
a. Free playFree play:
3 ~ 5 mm
1. Adjusting nut
2. Locknut
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-13
6
EAU00637
Valve clearance adjustmentThe correct valve clearance changes
with use, resulting in improper fuel/air
supply or engine noise. To prevent this,
the valve clearance must be adjusted
regularly. This adjustment however,
should be left to a professional
Yamaha service technician.
EAU00647
TiresTo ensure maximum performance,
long service, and safe operation, note
the following:
Tire air pressure
Always check and adjust the tire pres-
sure before operating the motorcycle.
EW000082
WARNING
@ Tire inflation pressure should be
checked and adjusted when the
temperature of the tire equals the
ambient air temperature. Tire infla-
tion pressure must be adjusted ac-
cording to total weight of cargo,
rider, passenger, and accessories
(fairing, saddlebags, etc. if approved
for this model), and vehicle speed. @
CE-32EMaximum load* 160 kg
Cold tire pressure Front Rear
Up to 90 kg*175 kPa
(1.75 kg/cm
2,
1.75 bar)200 kPa
(2.00 kg/cm
2,
2.00 bar)
90 kg load ~
Maximum load*175 kPa
(1.75 kg/cm
2,
1.75 bar)225 kPa
(2.25 kg/cm
2,
2.25 bar)
* Load is the total weight of cargo, rider, passenger
and accessories.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-22
6
EAU01533
Drive chain slack adjustment1. Loosen the rear brake adjusting
nut.
2. Loosen the wheel axle nut.3. To tighten the chain, turn the chain
adjusting plates in direction
a.
To loosen the chain, turn the chain
adjusting plates in direction
b and
push the wheel forward. Turn each
chain adjusting plate to exactly the
same position to maintain correct
axle alignment.
EC000096
CAUTION:@ Too little chain slack will overload
the engine and other vital parts.
Keep the slack within the specified
limits. @
4. Tighten the wheel axle nut to the
specified torque.
5. Adjust the brake pedal free play.
EW000103
WARNING
@ Check the operation of the brake
light after adjusting the rear brake. @
1. Adjusting nut
1. Axle nut
2. Chain adjusting plate
Tightening torque:
Wheel axle nut:
65 Nm (6.5 m·kg)
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