2002 YAMAHA DT125R Owners Manual

6-19
PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU04259
TiresTo maximize the performance, dura-
bility, and safe operation of your
motorcycle, note the following points
regarding the specified tires.
Tire air pressure
The tire air pressure should be
checked and, if necessary, adjusted
before each ride.
EW000082
w8The tire air pressure must be
checked and adjusted on cold
tires (i.e., when the tempera-
ture of the tires equals the
ambient temperature).
8The tire air pressure must be
adjusted in accordance with
the riding speed and with the
total weight of rider, passen-
ger, cargo, and accessories
approved for this model.
8NEVER OVERLOAD THE
MOTORCYCLE! Operation of
an overloaded motorcycle may
result in tire damage, loss of
control, or severe injury. Make
sure that the total weight of
rider, passenger, cargo, and
accessories does not exceed
the specified maximum load
for the vehicle.
8Do not carry along loosely
packed items, which can shift
during a ride.
8Securely pack the heaviest
items close to the center of the
motorcycle and distribute the
weight evenly on both sides.
8Adjust the suspension and tire
air pressure with regard to the
load.
8Check the tire condition and
air pressure before each ride.
EWA00012
wBecause loading has an enormous
impact on the handling, braking,
performance and safety character-
istics of your motorcycle, you
should keep the following precau-
tions in mind.
Tire air pressure
(measured on cold tires)
Load* Front Rear
Up to 90 kg125 kPa
(1.25 kgf/cm
2,
1.25 bar)150 kPa
(1.50 kgf/cm
2,
1.50 bar)
90 kg–
maximum150 kPa
(1.50 kgf/cm
2,
1.50 bar175 kPa
(1.75 kgf/cm
2,
1.75 bar)
Off-road riding125 kPa
(1.25 kgf/cm
2,
1.25 bar)150 kPa
(1.50 kgf/cm
2,
1.50 bar)
Maximum load*180 kg
178 kg (CH, A only)
* Total weight of rider, passenger, cargo and
accessories
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6-20
PERIODIC MAINTENANCE AND MINOR REPAIR
6 Tire inspection
The tires must be checked before
each ride. If the center tread depth
reaches the specified limit, if the tire
has a nail or glass fragments in it, or
if the sidewall is cracked, have a
Yamaha dealer replace the tire imme-
diately.
NOTE:
The tire tread depth limits may differ
from country to country. Always com-
ply with the local regulations.
1
2
1. Tread depth
2. Tire side wall
EAU00681
w8Have a Yamaha dealer replace
excessively worn tires.
Besides being illegal, operat-
ing the motorcycle with exces-
sively worn tires decreases
riding stability and can lead to
loss of control.
8The replacement of all wheel-
and brake-related parts,
including the tires, should be
left to a Yamaha dealer, who
has the necessary profession-
al knowledge and experience.
8It is not recommended to
patch a punctured tube. If
unavoidable, however, patch
the tube very carefully and
replace it as soon as possible
with a high-quality product.
Tire information
This motorcycle is equipped with tube
tires.
EW000078
w8The front and rear tires should
be of the same make and
design, otherwise the handling
characteristics of the motorcy-
cle cannot be guaranteed.
8After extensive tests, only the
tires listed below have been
approved for this model by
Yamaha Motor Co., Ltd.
Minimum tire tread depth
(front and rear)1.6 mm
FRONT
Manufacturer Size TypeBRIDGESTONE
2.75-21 45P TW25
REAR
Manufacturer Size Type
BRIDGESTONE
4.10-18 59P TW44
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PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU00685
Spoke wheelsTo maximize the performance, dura-
bility, and safe operation of your
motorcycle, note the following points
regarding the specified wheels.
8The wheel rims should be
checked for cracks, bends or
warpage, and the spokes for
looseness or damage before
each ride. If any damage is
found, have a Yamaha dealer
replace the wheel. Do not
attempt even the smallest repair
to the wheel. A deformed or
cracked wheel must be replaced.
8The wheel should be balanced
whenever either the tire or wheel
has been changed or replaced.
An unbalanced wheel can result
in poor performance, adverse
handling characteristics, and a
shortened tire life. 8Ride at moderate speeds after
changing a tire since the tire sur-
face must first be “broken in” for
it to develop its optimal charac-
teristics.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU00694
Adjusting the clutch lever
free playThe clutch lever free play should
measure 10–15 mm as shown.
Periodically check the clutch lever
free play and, if necessary, adjust it
as follows.
1. Loosen the locknut at the clutch
lever.
2. To increase the clutch lever free
play, turn the adjusting bolt in
direction a. To decrease the
clutch lever free play, turn the
adjusting bolt in direction b.
12b
a c
1. Locknut (Clutch lever)
2. Adjusting bolt
c. Free play
5. Loosen the locknut at the
crankcase.
6. To increase the clutch lever free
play, turn the adjusting nut in
direction a. To decrease the
clutch lever free play, turn the
adjusting nut in direction b.
7. Tighten the locknut at the clutch
lever and the crankcase.
a
21
b
1. Locknut (Crankcase)
2. Adjusting nut
3. If the specified clutch lever free
play could be obtained as
described above, tighten the
locknut and skip the rest of the
procedure, otherwise proceed as
follows.
4. Fully turn the adjusting bolt at the
clutch lever in direction ato
loosen the clutch cable.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU00712
Adjusting the brake pedal
positionThe top of the brake pedal should be
positioned approximately 15 mm
below the top of the footrest as
shown. Periodically check the brake
pedal position and, if necessary,
have a Yamaha dealer adjust it.
a
1
1. Footrest
a. Brake pedal position
EW000099
w8After adjusting the brake lever
free play, check the free play
and make sure that the brake
is working properly.
8A soft or spongy feeling in the
brake lever can indicate the
presence of air in the
hydraulic system. If there is air
in the hydraulic system, have
a Yamaha dealer bleed the
system before operating the
motorcycle. Air in the
hydraulic system will diminish
the braking performance,
which may result in loss of
control and an accident.
EAU00696
Adjusting the brake lever
free playThe brake lever free play should
measure 2–5 mm as shown.
Periodically check the brake lever
free play and, if necessary, adjust it
as follows.
1. Loosen the locknut at the brake
lever.
2. To increase the brake lever free
play, turn the adjusting bolt in
direction a. To decrease the
brake lever free play, turn the
adjusting bolt in direction b.
3. Tighten the locknut.
2
1b
a
c
1. Locknut
2. Adjusting bolt
c. Free play
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PERIODIC MAINTENANCE AND MINOR REPAIR
6
EW000109
wA soft or spongy feeling in the
brake pedal can indicate the pres-
ence of air in the hydraulic system.
If there is air in the hydraulic sys-
tem, have a Yamaha dealer bleed
the system before operating the
motorcycle. Air in the hydraulic
system will diminish the braking
performance, which may result in
loss of control and an accident.
EAU00721
Checking the front and rear
brake padsThe front and rear brake pads must
be checked for wear at the intervals
specified in the periodic maintenance
and lubrication chart.
EAU00713
Adjusting the rear brake light
switchThe rear brake light switch, which is
activated by the brake pedal, is prop-
erly adjusted when the brake light
comes on just before braking takes
effect. If necessary, adjust the brake
light switch as follows.
Turn the adjusting nut while holding
the rear brake light switch in place.
To make the brake light come on ear-
lier, turn the adjusting nut in direction
a. To make the brake light come on
later, turn the adjusting nut in direc-
tion b.
b
a 1
2
1. Brake light switch
2. Adjusting nut
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PERIODIC MAINTENANCE AND MINOR REPAIR
6
EAU00724
Front brake pads
Each front brake pad is provided with
a wear indicator, which allows you to
check the brake pad wear without
having to disassemble the brake. To
check the brake pad wear, check the
position of the wear indicator while
applying the brake. If a brake pad
has worn to the point that the wear
indicator almost touches the brake
disc, have a Yamaha dealer replace
the brake pads as a set.
1
1. Wear indicator
EAU03776
Checking the brake fluid
levelInsufficient brake fluid may allow air
to enter the brake system, possibly
causing it to become ineffective.
Before riding, check that the brake
fluid is above the minimum level mark
and replenish if necessary. A low
brake fluid level may indicate worn
brake pads and/or brake system
leakage. If the brake level is low, be
sure to check the brake pads for
wear and the brake system for leak-
age.
1
1. Minimum level mark
EAU00728
Rear brake pads
Each rear brake pad is provided with
a wear indicator, which allows you to
check the brake pad wear without
having to disassemble the brake. To
check the brake pad wear, check the
position of the wear indicator while
applying the brake. If a brake pad
has worn to the point that the wear
indicator almost touches the brake
disc, have a Yamaha dealer replace
the brake pads as a set.
1
1. Wear indicator
FRONT
REAR
FRONT
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PERIODIC MAINTENANCE AND MINOR REPAIR
6 Observe these precautions:
8When checking the fluid level,
make sure that the top of the
brake fluid reservoir is level.
8Use only the recommended qual-
ity brake fluid, otherwise the rub-
ber seals may deteriorate, caus-
ing leakage and poor braking
performance.
1
1. Minimum level mark
EAU03976
Changing the brake fluidHave a Yamaha dealer change the
brake fluid at the intervals specified in
the NOTE after the periodic mainte-
nance and lubrication chart. In addi-
tion, have the oil seals of the master
cylinders and calipers as well as the
brake hoses replaced at the intervals
listed below or whenever they are
damaged or leaking.
8Oil seals: Replace every two
years.
8Brake hoses: Replace every four
years. 8Refill with the same type of brake
fluid. Mixing fluids may result in a
harmful chemical reaction and
lead to poor braking perfor-
mance.
8Be careful that water does not
enter the brake fluid reservoir
when refilling. Water will signifi-
cantly lower the boiling point of
the fluid and may result in vapor
lock.
8Brake fluid may deteriorate paint-
ed surfaces or plastic parts.
Always clean up spilled fluid
immediately.
8As 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
suddenly, have a Yamaha dealer
check the cause.
REARRecommended brake fluid:
DOT 4
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