brake YAMAHA YZF-R6 2003 User Guide

PERIODIC MAINTENANCE AND MINOR REPAIR
6-29
6
EAU01357
Adjusting the brake pedal
position The top of the brake pedal should be
positioned approximately 7–11 mm be-
low the bottom of the footrest bracket
as shown. Periodically check the brake
pedal position and, if necessary, have
a Yamaha dealer adjust it.
EW000109
WARNING
_ A soft or spongy feeling in the brake
pedal 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 be-
fore operating the motorcycle. Air in
the hydraulic system will diminish
the braking performance, which
may result in loss of control and an
accident. _
EAU00713
Adjusting the rear brake light
switch The rear brake light switch, which is ac-
tivated by the brake pedal, is properly
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 earlier,
turn the adjusting nut in direction
a. To
make the brake light come on later,
turn the adjusting nut in direction
b.
a. Distance between brake pedal and footrest
bracket
1. Rear brake light switch
2. Rear brake light switch adjusting nut
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-30
6
EAU00721
Checking the front and rear
brake pads The front and rear brake pads must be
checked for wear at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
EAU00724
Front brake pads
Each front brake pad is provided with a
wear indicator, which allows you to
check the brake pad wear without hav-
ing 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.
EAU04510
Rear brake pads
Check each rear brake pad for damage
and measure the lining thickness. If a
brake pad is damaged or if the lining
thickness is less than 1.0 mm, have a
Yamaha dealer replace the brake pads
as a set.
1. Brake pad wear indicatorFront
a. Lining thicknessRear
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-31
6
EAU04856
Checking the brake fluid level Insufficient brake fluid may allow air to
enter the brake system, possibly caus-
ing it to become ineffective.
Before riding, check that the brake fluid
is above the minimum level mark and
replenish if necessary. A low brake flu-
id level may indicate worn brake pads
and/or brake system leakage. If the
brake fluid level is low, be sure to check
the brake pads for wear and the brake
system for leakage.Observe these precautions:


When checking the fluid level,
make sure that the top of the brake
fluid reservoir is level.


Use only the recommended quali-
ty brake fluid, otherwise the rubber
seals may deteriorate, causing
leakage and poor braking perfor-
mance.


Refill with the same type of brake
fluid. Mixing fluids may result in a
harmful chemical reaction and
lead to poor braking performance.


Be careful that water does not en-
ter the brake fluid reservoir when
refilling. Water will significantly
lower the boiling point of the fluid
and may result in vapor lock.


Brake fluid may deteriorate paint-
ed surfaces or plastic parts. Al-
ways clean up spilled fluid
immediately.


As 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.
1. Minimum level markFront
1. Minimum level mark
Recommended brake fluid: DOT 4Rear
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-32
6
EAU03976
Changing the brake fluid Have a Yamaha dealer change the
brake fluid at the intervals specified in
the NOTE after the periodic mainte-
nance and lubrication chart. In addition,
have the oil seals of the master cylin-
ders and calipers as well as the brake
hoses replaced at the intervals listed
below or whenever they are damaged
or leaking.

Oil seals: Replace every two
years.


Brake hoses: Replace every four
years.
EAU00744
Drive chain slack The drive chain slack should be
checked before each ride and adjusted
if necessary.
To check the drive chain slack
1. Place the motorcycle on a level
surface and hold it in an upright
position.NOTE:@ When checking and adjusting the drive
chain slack, the motorcycle should be
positioned straight up and there should
be no weight on it. @2. Shift the transmission into the neu-
tral position.3. Move the rear wheel by pushing
the motorcycle to locate the tight-
est portion of the drive chain, and
then measure the drive chain
slack as shown.
4. If the drive chain slack is incorrect,
adjust it as follows.
a. Drive chain slackDrive chain slack:
35–45 mm
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-35
6
EAU03164
Checking and lubricating the
brake and clutch levers The operation of the brake and clutch
levers should be checked before each
ride, and the lever pivots should be lu-
bricated if necessary.
EAU03370
Checking and lubricating the
brake and shift pedals The operation of the brake and shift
pedals should be checked before each
ride, and the pedal pivots should be lu-
bricated if necessary.
Recommended lubricant:
Lithium-soap-based grease
(all-purpose grease)
Recommended lubricant:
Lithium-soap-based grease
(all-purpose grease)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-37
6
EAU02939
Checking the front fork The 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
EW000115
WARNING
@ Securely 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
surface and hold it in an upright
position.
2. While applying the front brake,
push down hard on the handle-
bars several times to check if the
front fork compresses and re-
bounds smoothly.
EC000098
CAUTION:@ If any damage is found or the front
fork does not operate smoothly,
have a Yamaha dealer check or re-
pair it. @
EAU00794
Checking the steering Worn 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 pe-
riodic maintenance and lubrication
chart.
1. Place a stand under the engine to
raise the front wheel off the
ground.
EW000115
WARNING
@ Securely support the motorcycle so
that there is no danger of it falling
over. @
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-44
6
NOTE:_ To install the quick fastener, push the
center pin out so that it will protrude
from the fastener head, insert the fas-
tener into the auxiliary light bulb cover,
and then push the protruding pin in until
it is flush with the fastener head. _
EAU03730
Tail/brake light This motorcycle is equipped with an
LED type of tail/brake light.
If the tail/brake light does not come on,
have a Yamaha dealer check it.
EAU03497
Replacing a turn signal light
bulb 1. Remove the turn signal light lens
by removing the screw.
2. Remove the defective bulb by
pushing it in and turning it
counterclockwise.
3. Insert a new bulb into the socket,
push it in, and then turn it clock-
wise until it stops.
4. Install the lens by installing the
screw.
ECA00065
CAUTION:@ Do not overtighten the screw, other-
wise the lens may break. @
1. Quick fastener
2. Pin
After removal
Before installation
1. Screw
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-46
6 To service the rear wheel
Raise the rear wheel off the ground by
using a motorcycle stand or, if a motor-
cycle stand is not available, by placing
a jack either under each side of the
frame in front of the rear wheel or under
each side of the swingarm.
EAU04956
Front wheel To remove the front wheel
EW000122
WARNING
_

It is advisable to have a Yamaha
dealer service the wheel.


Securely support the motor-
cycle so that there is no danger
of it falling over.
_1. Loosen the axle bolt, the wheel
axle pinch bolts, and then the
brake caliper bolts.2. Lift the front wheel off the ground
according to the procedure on
page 6-45.
3. Remove the brake hose holder on
each side by removing the bolt.
4. Remove the brake caliper on each
side by removing the bolts.1. Front wheel axle pinch bolt (× 4)
1. Brake hose holder
2. Brake caliper
3. Axle bolt
4. Bolt (× 3)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-47
65. Remove the axle bolt, pull the
wheel axle out, and then remove
the wheel.
ECA00046
CAUTION:_ Do not apply the brake after the
brake calipers have been removed,
otherwise the brake pads will be
forced shut. _
EAU05021
To install the front wheel
1. Lift the wheel up between the fork
legs.
2. Insert the wheel axle.
3. Lower the front wheel so that it is
on the ground.
4. Install the brake calipers by install-
ing the bolts, and then tightening
them to the specified torque.NOTE:_ Make sure that there is enough space
between the brake pads before install-
ing the brake calipers onto the brake
discs. _5. Install the brake hose holders by
installing the bolts.
6. Secure the wheel axle by installing
the axle bolt, and then tightening
the wheel axle to the specified
torque.
NOTE:_ While tightening the wheel axle, hold
the axle bolt to keep it from turning. _
1. Wheel axle
Tightening torque:
Brake caliper bolt:
40 Nm (4.0 m·kgf)
Tightening torque:
Wheel axle:
91 Nm (9.1 m·kgf)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-48
6 7. Tighten wheel axle pinch bolt B,
and then tighten pinch bolt A to the
specified torque.
8. Retighten pinch bolt B to the spec-
ified torque.
9. Tap the outer side of the left fork
leg with a rubber mallet to align it
with the end of the wheel axle.10. Tighten wheel axle pinch bolt D,
and then tighten pinch bolt C to the
specified torque.
11. Retighten pinch bolt D to the spec-
ified torque.
12. While applying the front brake,
push down hard on the handlebar
several times to check for proper
fork operation.
1. Front wheel axle pinch bolt A
2. Front wheel axle pinch bolt B
3. Front wheel axle pinch bolt C
4. Front wheel axle pinch bolt D
Tightening torque:
Wheel axle pinch bolt:
18 Nm (1.8 m·kgf)
Tightening torque:
Wheel axle pinch bolt:
18 Nm (1.8 m·kgf)
E_5sl_Periodic.fm Page 48 Thursday, October 17, 2002 1:13 PM