2000 YAMAHA SR125 maintenance

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.
E_3mw.book Page 15 Monday, February 5, 2001 9:54 AM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-16
6
EAU00692
Clutch lever free play
adjustmentThe clutch lever free play should be ad-
justed to 10 ~ 15 mm. If the free play is
incorrect, adjust as follows.
1. Loosen the locknut.
2. Turn the adjusting bolt at the
clutch lever in direction
a to in-
crease free play or in direction
b
to decrease free play.
3. Tighten the locknut.
NOTE:@ If proper adjustment cannot be ob-
tained or the clutch does not work cor-
rectly, ask a Yamaha dealer to inspect
the internal clutch mechanism. @
EAU00696
Front brake lever free play
adjustmentThe free play at the front brake lever
should be 2 ~ 5 mm.
1. Loosen the locknut.
2. Turn the adjusting bolt in
direction
a to increase free play
or in direction
b to decrease free
play.
3. After adjusting, tighten the locknut.
1. Locknut
2. Adjusting bolt
c. Free play
1. Locknut
2. Adjusting bolt
c. Free play
E_3mw.book Page 16 Monday, February 5, 2001 9:54 AM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-17
6
EW000099
WARNING
@ l
Check the brake lever free play.
Be sure the brake is working
properly.
l
A soft or spongy feeling in the
brake lever can indicate the
presence of air in the brake sys-
tem. This air must be removed
by bleeding the brake system
before the motorcycle is operat-
ed. Air in the system will cause
greatly diminished braking ca-
pability and can result in loss of
control and an accident. Have a
Yamaha dealer inspect and
bleed the system if necessary.
@
EAU01105
Rear brake pedal height and
free play adjustment
EW000104
WARNING
@ It is advisable to have a Yamaha
dealer make this adjustment. @
Pedal height
The pedal height should be adjusted so
that the top of brake pedal is aligned
with the top of footrest.
1. Loosen the locknut.
2. Turn the adjusting bolt in
direction
a to raise the brake ped-
al or in direction
b to lower the
brake pedal.
3. Tighten the locknut.
EW000105
WARNING
@ After adjusting the pedal height, ad-
just brake pedal free play. @
1. Adjusting bolt (for pedal height)
2. Locknut
3. Pedal height
c. Free play
E_3mw.book Page 17 Monday, February 5, 2001 9:54 AM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-18
6Free play
The free play at the end of the brake
pedal should be approximately 20 ~
30 mm. Turn the adjusting nut in direc-
tion
a to increase the brake pedal free
play or in direction
b to reduce the
brake pedal free play.
EW000103
WARNING
@ Check the operation of the brake
light after adjusting the rear brake. @
EAU01646
Brake light switch adjustmentThe rear brake light switch is activated
by the brake pedal and is properly ad-
justed when the brake light comes on
just before braking takes effect. Adjust
the brake light switch as follows.
1. Remove panel A.
2. Remove the battery cover by re-
moving the screw.3. Hold the switch body so it does not
rotate while turning the adjusting
nut.
4. Turn the adjusting nut in
direction
a to make the brake
light come on earlier. Turn the ad-
justing nut in direction
b to make
the brake light come on later.
1. Adjusting nut
1. Battery cover
2. Screw
1. Brake light switch
2. Adjusting nut
E_3mw.book Page 18 Monday, February 5, 2001 9:54 AM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-19
6
EAU00720
Checking the front brake pads
and rear brake shoes
EAU01119
Front brake
Wear indicator grooves are provided
on each brake pad. These indicators
allow checking of brake pad wear with-
out disassembling the brake. Inspect
the grooves. If they have almost disap-
peared, ask a Yamaha dealer to re-
place the pads.
EAU00727
Rear brake
Apply the brake and inspect the wear
indicator.
If the indicator reaches the wear limit
line, ask a Yamaha dealer to replace
the shoes.
1. Wear indicator groove (´ 2)
2. Brake pads
1. Wear limit
2. Wear indicator
E_3mw.book Page 19 Monday, February 5, 2001 9:54 AM

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
E_3mw.book Page 20 Monday, February 5, 2001 9:54 AM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-21
6
EAU00746
Drive chain slack checkNOTE:@ Spin the wheel several times and find
the tightest position of the chain. Check
and/or adjust the chain slack while it’s
in this tightest position. @The chain slack should be checked
through the inspection window in the
chain case by the following procedure.
1. Place the motorcycle on the cen-
terstand.
2. Put the transmission in neutral.
3. While looking in the inspection
window, rotate the rear wheel.4. Chain slack is correct if the full end
of the chain link can be seen in the
usable range as shown in illustra-
tion.
5. If any portion of the top or bottom
of the chain link end is hidden, ad-
just the chain.1. Inspection window
1. USABLE RANGE
2. Too tight
3. Too loose
E_3mw.book Page 21 Monday, February 5, 2001 9:54 AM

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)
E_3mw.book Page 22 Monday, February 5, 2001 9:54 AM