YAMAHA SR400 2016 Repair Manual

Periodic maintenance and adjustment
6-23
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EAU22541Rear brake shoes
The rear brake is provided with a wear
indicator, which allows you to check the
brake shoe wear without having to dis-
assemble the brake. To check the
brake shoe wear, check the position of
the wear indicator while applying the
brake. If a brake shoe has worn to the
point that the wear indicator reaches
the wear limit line, have a Yamaha
dealer replace the brake shoes as a
set.EAU32346
Checking the brake fluid level
Before riding, check that the brake fluid
is above the minimum level mark.
Check the brake fluid level with the top
of the reservoir level. Replenish the
brake fluid if necessary.
WARNING
EWA15991
Improper maintenance can result in
loss of braking ability. Observe
these precautions:
Insufficient brake fluid may al-
low air to enter the brake sys-
tem, reducing braking
performance.
Clean the filler cap before re-
moving. Use only DOT 4 brake
fluid from a sealed container.
Use only the specified brake flu-
id; otherwise, the rubber seals
may deteriorate, causing leak-
age.
Refill with the same type of
brake fluid. Adding a brake fluid
other than DOT 4 may result in a
harmful chemical reaction.
Be careful that water does not
enter the brake fluid reservoir
1. Brake shoe wear indicator
2. Brake shoe wear limit line
1 2
1. Minimum level mark
Specified brake fluid:
DOT 4
1
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Periodic maintenance and adjustment
6-24
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14 when refilling. Water will signifi-
cantly lower the boiling point of
the fluid and may result in vapor
lock.
NOTICE
ECA17641
Brake fluid may damage painted sur-
faces or plastic parts. Always clean
up spilled fluid immediately.
As the brake pads wear, it is normal for
the brake fluid level to gradually go
down. A low brake fluid level may indi-
cate worn brake pads and/or brake sys-
tem leakage; therefore, be sure to
check the brake pads for wear and the
brake system for leakage. If the brake
fluid level goes down suddenly, have a
Yamaha dealer check the cause before
further riding.
EAU22724
Changing the brake fluid
Have a Yamaha dealer change the
brake fluid at the intervals specified in
the periodic maintenance and lubrica-
tion chart. In addition, have the oil seals
of the brake master cylinder and caliper
as well as the brake hose replaced at
the intervals listed below or whenever
they are damaged or leaking.
Oil seals: Replace every two
years.
Brake hose: Replace every four
years.
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Periodic maintenance and adjustment
6-25
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EAU22762
Drive chain slack
The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU59593To check the drive chain slack 1. Place the motorcycle on the cen- terstand.
2. Shift the transmission into the neu- tral position.
3. Push on the drive chain at the cen- ter point between the drive axle
and the rear wheel axle with a
force of 50 N (5.0 kgf, 11 lbf).
4. Measure the drive chain slack as shown.
5. If the drive chain slack is incorrect, adjust it as follows.
EAU59642To adjust the drive chain slack
Consult a Yamaha dealer before ad-
justing the drive chain slack.1. Take the motorcycle off the center- stand, and then put the sidestand
down.
2. Loosen the brake pedal free play adjusting nut, brake torque rod nut,
and axle nut.
3. Loosen the drive chain puller lock- nut at each end of the swingarm.
4. Place the motorcycle on the cen- terstand.
5. To tighten the drive chain, turn the drive chain slack adjusting bolt at
each end of the swingarm in direc-
tion (a). To loosen the drive chain,
turn the adjusting bolt at each end
of the swingarm in direction (b),
and then push the rear wheel for-
ward. NOTICE: Improper drive
chain slack will overload the en-
gine as well as other vital parts
of the motorcycle and can lead
to chain slippage or breakage.
To prevent this from occurring,
keep the drive chain slack with-
in the specified limits.[ECA10572]
TIP
Using the alignment marks on each
side of the swingarm, make sure that
both drive chain pullers are in the same
position for proper wheel alignment.
Drive chain slack: 30.0–40.0 mm (1.18–1.57 in)
1. Drive chain slack
1
1. Brake pedal free play adjusting nut
2. Drive chain slack adjusting bolt
3. Drive chain puller locknut
4. Axle nut
5. Brake torque rod nut
6. Brake torque rod
6
12
3
4
5
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Periodic maintenance and adjustment
6-26
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14 6. Take the motorcycle off the center-
stand, and then put the sidestand
down.
7. Tighten both drive chain puller locknuts to the specified torque,
and then tighten the axle nut and
brake torque rod nut to their speci-
fied torques.
8. Adjust the brake pedal free play. (See page 6-20.)
WARNING
EWA10661
After adjusting the brake pedal free
play, check the operation of the
brake light.
9. Make sure that the drive chain pull- ers are in the same position, the
drive chain slack is correct, and the
drive chain moves smoothly.
EAU23026
Cleaning and lubricating the
drive chain
The drive chain must be cleaned and
lubricated at the intervals specified in
the periodic maintenance and lubrica-
tion chart, otherwise it will quickly wear
out, especially when riding in dusty or
wet areas. Service the drive chain as
follows.
NOTICE
ECA10584
The drive chain must be lubricated
after washing the motorcycle, riding
in the rain or riding in wet areas.
1. Clean the drive chain with kero- sene and a small soft brush.
NOTICE: To prevent damaging
the O-rings, do not clean the
drive chain with steam cleaners,
high-pressure washers or inap-
propriate solvents.
[ECA11122]
2. Wipe the drive chain dry.
3. Thoroughly lubricate the drive chain with a special O-ring chain
lubricant. NOTICE: Do not use
engine oil or any other lubri-
cants for the drive chain, as they
may contain substances that
could damage the O-rings.
[ECA11112]
1. Axle nut
2. Drive chain puller locknut
3. Drive chain slack adjusting bolt
4. Alignment marks
Tightening torques: Drive chain puller locknut:16 Nm (1.6 m·kgf, 12 ft·lbf)
Axle nut: 129 Nm (12.9 m·kgf, 92 ft·lbf)
Brake torque rod nut:
19 Nm (1.9 m·kgf, 14 ft·lbf)
1
2
(a) (b)
3
4
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Periodic maintenance and adjustment
6-27
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EAU23098
Checking and l ubricating the
cables
The operation of all control cables and
the condition of the cables should be
checked before each ride, and the ca-
bles and cable ends should be lubricat-
ed if necessary. If a cable is damaged
or does not move smoothly, have a
Yamaha dealer check or replace it.
WARNING! Damage to the outer
housing of cables may result in in-
ternal rusting and cause interfer-
ence with cable movement. Replace
damaged cables as soon as possi-
ble to prevent unsafe condi-
tions.
[EWA10712] EAU23115
Checking and lubricating the
throttle grip and cable
The operation of the throttle grip should
be checked before each ride. In addi-
tion, the cable should be lubricated by a
Yamaha dealer at the intervals speci-
fied in the periodic maintenance chart.
The throttle cable is equipped with a
rubber cover. Make sure that the cover
is securely installed. Even though the
cover is installed correctly, it does not
completely protect the cable from water
entry. Therefore, use care not to pour
water directly onto the cover or cable
when washing the vehicle. If the cable
or cover becomes dirty, wipe clean with
a moist cloth.
Recommended lubricant:
Yamaha cable lubricant or other suit-
able cable lubricant
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Periodic maintenance and adjustment
6-28
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EAU23144
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.
Brake lever
Clutch lever
EAU23185
Checking and l ubricating the
brake pedal
The operation of the brake pedal
should be checked before each ride,
and the pedal pivot should be lubricat-
ed if necessary.
Recommended lubricants: Brake lever:Silicone grease
Clutch lever:
Lithium-soap-based grease
Recommended lubricant:Lithium-soap-based grease
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Periodic maintenance and adjustment
6-29
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EAU23215
Checking and l ubricating the
centerstand and sidestand
The operation of the centerstand and
sidestand should be checked before
each ride, and the pivots and metal-to-
metal contact surfaces should be lubri-
cated if necessary.
WARNING
EWA10742
If the centerstand or sidestand does
not move up and down smoothly,
have a Yamaha dealer check or re-
pair it. Otherwise, the centerstand or
sidestand could contact the ground
and distract the operator, resulting
in a possible loss of control.
EAUM1653
Lubricating the swingarm
pivots
The swingarm pivots must be lubricat-
ed by a Yamaha dealer at the intervals
specified in the periodic maintenance
and lubrication chart.
Recommended lubricant: Lithium-soap-based grease
Recommended lubricant:
Lithium-soap-based grease
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Periodic maintenance and adjustment
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EAU51951
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
Check the front fork for damage and ex-
cessive oil leakage.
To check the operation 1. Place the vehicle on a level sur- face and hold it in an upright posi-
tion. WARNING! To avoid injury,
securely support the vehicle so
there is no danger of it falling
over.
[EWA10752]
2. While applying the front brake, push down hard on the handlebars
several times to check if the front
fork compresses and rebounds
smoothly.
NOTICE
ECA10591
If any damage is found or the front
fork does not operate smoothly,
have a Yamaha dealer check or re-
pair it.
EAU45512
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 the vehicle on the center- stand. WARNING! To avoid inju-
ry, securely support the vehicle
so there is no danger of it falling
over.
[EWA10752]
2. Hold the lower ends of the front fork legs and try to move them for-
ward and backward. If any free
play can be felt, have a Yamaha
dealer check or repair the steering.
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Periodic maintenance and adjustment
6-31
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EAU23292
Checking the wheel bearings
The front and rear wheel bearings must
be checked at the intervals specified in
the periodic maintenance and lubrica-
tion chart. If there is play in the wheel
hub or if the wheel does not turn
smoothly, have a Yamaha dealer check
the wheel bearings.
EAU40447
Battery
The battery is located under the seat.
(See page 3-13.)
This model is equipped with a VRLA
(Valve Regulated Lead Acid) battery.
There is no need to check the electro-
lyte or to add distilled water. However,
the battery coupler connection needs to
be checked to make sure that it is se-
curely connected.
WARNING
EWA10761
Electrolyte is poisonous and
dangerous since it contains sul-
furic acid, which causes severe
burns. Avoid any contact with
skin, eyes or clothing and al-
ways shield your eyes when
working near batteries. In case
of contact, administer the fol-
lowing FIRST AID. EXTERNAL: Flush with plenty of water.
INTERNAL: Drink large quan- tities of water or milk and im-
mediately call a physician.
EYES: Flush with water for 15 minutes and seek prompt
medical attention.
Batteries produce explosive hy-
drogen gas. Therefore, keep
1. Battery
1
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Periodic maintenance and adjustment
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14 sparks, flames, cigarettes, etc.,
away from the battery and pro-
vide sufficient ventilation when
charging it in an enclosed
space.
KEEP THIS AND ALL BATTER-
IES OUT OF THE REACH OF
CHILDREN.
To charge the battery
Have a Yamaha dealer charge the bat-
tery as soon as possible if it seems to
have discharged. Keep in mind that the
battery tends to discharge more quickly
if the vehicle is equipped with optional
electrical accessories.
NOTICE
ECA16522
To charge a VRLA (Valve Regulated
Lead Acid) battery, a special (con-
stant-voltage) battery charger is re-
quired. Using a conventional battery
charger will damage the battery.
To store the battery 1. If the vehicle will not be used for more than one month, remove the
battery, fully charge it, and then
place it in a cool, dry place.
NOTICE: When removing the
battery, be sure the key is
turned to “OFF” before discon-
necting the coupler.
[ECA16323]
2. If the battery will be stored for more than two months, check it at least
once a month and fully charge it if
necessary.
3. Fully charge the battery before in- stallation. NOTICE: When install-
ing the battery, be sure the key
is turned to “OFF” before con- necting the coupler.
[ECA16931]
NOTICE
ECA16531
Always keep the battery charged.
Storing a discharged battery can
cause permanent battery damage.
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