2000 YAMAHA SR125 service

6-1
6
EAU00462
6-PERIODIC MAINTENANCE AND MINOR REPAIR
EAU00464
Periodic inspection, adjustment and lu-
brication will keep your motorcycle in
the safest and most efficient condition
possible. Safety is an obligation of the
motorcycle owner. The maintenance
and lubrication schedule chart should
be considered strictly as a guide to
general maintenance and lubrication
intervals. YOU MUST TAKE INTO
CONSIDERATION THAT WEATHER,
TERRAIN, GEOGRAPHICAL LOCA-
TIONS, AND A VARIETY OF INDIVID-
UAL USES ALL TEND TO DEMAND
THAT EACH OWNER ALTER THIS
TIME SCHEDULE TO SHORTER IN-
TERVALS TO MATCH THE ENVI-
RONMENT. The most important points
of motorcycle inspection, adjustment,
and lubrication are explained in the fol-
lowing pages.
EW000060
WARNING
@ If you are not familiar with motor-
cycle service, this work should be
done by a Yamaha dealer. @
EAU01175
Tool kitThe tool kit is located behind panel A.
(See page 6-5 for panel removal and
installation procedures.) The tools pro-
vided in the owner’s tool kit are to as-
sist you in the performance of periodic
maintenance. However, some other
tools such as a torque wrench are also
necessary to perform the maintenance
correctly.
The service information included in this
manual is intended to provide you, the
owner, with the necessary information
for completing some of your own pre-
ventive maintenance and minor re-
pairs.
NOTE:@ If you do not have necessary tools re-
quired during a service operation, take
your motorcycle to a Yamaha dealer for
service. @
EW000063
WARNING
@ Modifications to this motorcycle not
approved by Yamaha may cause
loss of performance, and render it
unsafe for use. Consult a Yamaha
dealer before attempting any chang-
es. @
1. Tool kit
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-4
6
EAU03541
NOTE:_l
The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
l
Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid level.
• Every two years replace the internal components of the brake master cylinder and caliper, and change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.
_26
*Lights, signals and
switches• Check operation.
• Adjust headlight beam.ÖÖÖÖÖ 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
6-11
6
EAU00629
Carburetor adjustmentThe carburetor is a vital part of the en-
gine and requires very sophisticated
adjustment. Most adjustments should
be left to a Yamaha dealer who has the
professional knowledge and experi-
ence to do so. However, the following
may be serviced by the owner as part
of routine maintenance.
EC000094
CAUTION:@ The carburetor was set at the
Yamaha factory after many tests. If
the settings are changed, poor en-
gine performance and damage may
result. @
EAU01168
Idle speed adjustmentNOTE:@ A diagnostic tachometer must be used
for this procedure. @1. Attach the tachometer. Start the
engine and warm it up for a few
minutes at approximately 1,000 to
2,000 r/min. Occasionally rev the
engine to 4,000 to 5,000 r/min.
The engine is warm when it quick-
ly responds to the throttle.2. Set the idle to the specified engine
speed by adjusting the throttle
stop screw. Turn the screw in di-
rection
a to increase engine
speed and in direction
b to de-
crease engine speed.
NOTE:@ If the specified idle speed cannot be
obtained by performing the above ad-
justment, consult a Yamaha dealer. @1. Throttle stop screwStandard idle speed:
1,300 ~ 1,400 r/min
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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
6-15
6
EAU00681
WARNING
@ l
Operating the motorcycle with
excessively worn tires decrease
riding stability and can lead to
loss of control. Have excessive-
ly worn tires replaced by a
Yamaha dealer immediately.
Brakes, tires, and related wheel
parts replacement should be
left to a Yamaha Service Techni-
cian.
l
Patching a punctured tube is
not recommended. If it is abso-
lutely necessary to do so, use
great care and replace the tube
as soon as possible with a good
quality replacement.
@
EAU00685
WheelsTo ensure maximum performance,
long service, and safe operation, note
the following:l
Always inspect the wheels before
a ride. Check for cracks, bends or
warpage of the wheel. Be sure the
spokes are tight and undamaged.
If any abnormal condition exists in
a wheel, consult a Yamaha dealer.
Do not attempt even small repairs
to the wheel. If a wheel is de-
formed or cracked, it must be re-
placed.
l
Tires and wheels should be bal-
anced whenever either one is
changed or replaced. Failure to
have a wheel balanced can result
in poor performance, adverse han-
dling characteristics, and short-
ened tire life.
l
Ride at moderate speeds after
changing a tire since the tire sur-
face must first be broken in for it to
develop its optimal characteristics.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-20
6
EAU00732
Inspecting the brake fluid
levelInsufficient brake fluid may let air enter
the brake system, possibly causing the
brakes to become ineffective.
Before riding, check that the brake fluid
is above the minimum level and fill
when necessary.
Observe these precautions:l
When checking the fluid level,
make sure the top of the master
cylinder is level by turning the han-
dlebars.
l
Use only the designated quality
brake fluid. Otherwise, the rubber
seals may deteriorate, causing
leakage and poor brake perfor-
mance.
NOTE:@ If DOT 4 is not available, DOT 3 can be
used. @l
Refill with the same type of brake
fluid. Mixing fluids may result in a
harmful chemical reaction and
lead to poor brake performance.
l
Be careful that water does not en-
ter the master cylinder when refill-
ing. Water will significantly lower
the boiling point of the fluid and
may result in vapor lock.
l
Brake fluid may deteriorate paint-
ed surfaces or plastic parts. Al-
ways clean up spilled fluid
immediately.
l
Have a Yamaha dealer check the
cause if the brake fluid level goes
down.
EAU00742
Brake fluid replacementThe brake fluid should be replaced only
by trained Yamaha service personnel.
Have the Yamaha dealer replace the
following components during periodic
maintenance or when they are dam-
aged or leaking:l
oil seals (every two years)
l
brake hoses (every four years)
1. Minimum level mark
Recommended brake fluid: DOT 4
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-23
6
EAU01106*
Drive chain lubricationThe chain consists of many parts which
work with each other. If the chain is not
maintained properly, it will wear out
quickly. Therefore, the chain must be
serviced regularly. This service is es-
pecially necessary when riding in dusty
areas.
The drive chain should be lubricated
every 500 km. First, remove all dirt and
mud from the chain with a brush or
cloth. Then, spray any of the many
brands of spray-type chain lubricant
between both rows of side plates and
on all center rollers.
To clean the chain thoroughly, remove
it from the motorcycle, dip it in solvent,
and clean out as much dirt as possible.
Then, take the chain out of the solvent
to dry it, and immediately lubricate it to
prevent it from rusting.
EAU02962
Cable inspection and
lubrication
EW000112
WARNING
@ Damage to the outer housing of ca-
bles may lead to internal rusting and
interfere with the cable movement.
Replace damaged cables as soon as
possible to prevent unsafe condi-
tions. @Lubricate the cables and cable ends. If
a cable does not operate smoothly, ask
a Yamaha dealer to replace it.
EAU00773
Throttle cable and grip
lubricationThe throttle twist grip assembly should
be greased at the time that the cable is
lubricated, since the grip must be re-
moved to get at the end of the throttle
cable. After removing the screws, hold
the end of the cable up in the air and
put in several drops of lubricant. With
the throttle grip disassembled, coat the
metal surface of the grip assembly with
a suitable all-purpose grease.
Recommended lubricant:
Engine oil
E_3mw.book Page 23 Monday, February 5, 2001 9:54 AM