engine YAMAHA SR400 2014 User Guide

INSTRUMENT AND CONTROL FUNCTIONS
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EAU13125
Fuel tank capTo remove the fuel tank cap
Slide the fuel tank cap lock cover open,
insert the key into the lock, and then
turn it 1/4 turn clockwise. The lock will
be released and the fuel tank cap can
be removed.
To install the fuel tank cap 1. Insert the fuel tank cap into the tank opening with the key inserted
in the lock and with the “ ” mark
facing forward. 2. Turn the key counterclockwise to
the original position, remove it, and
then close the lock cover.
TIPThe fuel tank cap cannot be installed
unless the key is in the lock. In addition,
the key cannot be removed if the cap isnot properly installed and locked.
WARNING
EWA10132
Make sure that the fuel tank cap is
properly installed before riding.Leaking fuel is a fire hazard.
EAU13222
FuelMake sure there is sufficient gasoline in
the tank.
WARNING
EWA10882
Gasoline and gasoline vapors are
extremely flammable. To avoid fires
and explosions and to reduce the
risk of injury when refueling, followthese instructions.
1. Before refueling, turn off the en- gine and be sure that no one is sit-
ting on the vehicle. Never refuel
while smoking, or while in the vi-
cinity of sparks, open flames, or
other sources of ignition such as
the pilot lights of water heaters and
clothes dryers.
2. Do not overfill the fuel tank. When refueling, be sure to insert the
pump nozzle into the fuel tank filler
hole. Stop filling when the fuel
reaches the bottom of the filler
tube. Because fuel expands when
it heats up, heat from the engine or
the sun can cause fuel to spill out
of the fuel tank.
1. Unlock.
2. Fuel tank cap lock cover
2
1
1. “ ” mark
2. Fuel tank cap lock cover
1
2
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INSTRUMENT AND CONTROL FUNCTIONS
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3. Wipe up any spilled fuel immedi-
ately. NOTICE: Immediately wipe
off spilled fuel with a clean, dry,
soft cloth, since fuel may deteri-
orate painted surfaces or plastic
parts.
[ECA10072]
4. Be sure to securely close the fuel tank cap.
WARNING
EWA15152
Gasoline is poisonous and can
cause injury or death. Handle gaso-
line with care. Never siphon gaso-
line by mouth. If you should swallow
some gasoline or inhale a lot of gas-
oline vapor, or get some gasoline in your eyes, see your doctor immedi-
ately. If gasoline spills on your skin,
wash with soap and water. If gaso-
line spills on your clothing, change
your clothes.
EAU57690
NOTICE
ECA11401
Use only unleaded gasoline. The use
of leaded gasoline will cause severe
damage to internal engine parts,
such as the valves and piston rings,as well as to the exhaust system.
Your Yamaha engine has been de-
signed to use regular unleaded gaso-
line with a research octane number of
95 or higher. If knocking (or pinging) oc-
curs, use a gasoline of a different brandor premium unleaded fuel. Use of un-
leaded fuel will extend spark plug life
and reduce maintenance costs.
Gasohol
There are two types of gasohol: gaso-
hol containing ethanol and that contain-
ing methanol. Gasohol containing
ethanol can be used if the ethanol con-
tent does not exceed 10% (E10). Gas-
ohol containing methanol is not
recommended by Yamaha because it
can cause damage to the fuel system
or vehicle performance problems.
1. Maximum fuel level
2. Fuel tank filler tube
1
2
Recommended fuel:
Regular unleaded gasoline (Gasohol
(E10) acceptable)
Fuel tank capacity: 12.0 L (3.17 US gal, 2.64 Imp.gal)
Fuel reserve amount (when the fuel
level warning light comes on):
2.2 L (0.58 US gal, 0.48 Imp.gal)
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INSTRUMENT AND CONTROL FUNCTIONS
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EAU39453
Fuel tank breather/overflow
hoseBefore operating the motorcycle:
Check the fuel tank breather/over-
flow hose connection.

Check the fuel tank breather/over-
flow hose for cracks or damage,
and replace it if necessary.

Make sure that the end of the fuel
tank breather/overflow hose is not
blocked, and clean it if necessary.
EAU13434
Catalytic converterThis model is equipped with a catalytic
converter in the exhaust system.
WARNING
EWA10863
The exhaust system is hot after op-
eration. To prevent a fire hazard or
burns:
Do not park the vehicle near
possible fire hazards such as
grass or other materials that
easily burn.

Park the vehicle in a place
where pedestrians or children
are not likely to touch the hot
exhaust system.

Make sure that the exhaust sys-
tem has cooled down before do-
ing any maintenance work.

Do not allow the engine to idle
more than a few minutes. Long
idling can cause a build-up ofheat.
NOTICE
ECA10702
Use only unleaded gasoline. The use
of leaded gasoline will cause unre- pairable damage to the catalytic
converter.
1. Fuel tank breather/overflow hose
1
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INSTRUMENT AND CONTROL FUNCTIONS
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EAU59490
Fuel cockThe fuel cock regulates and filters the
fuel supply from the fuel pump to the
fuel injector.
The fuel cock has two positions:
ON
With the lever in this position, fuel will
be supplied to the engine. Normal oper-
ation is done with the lever in this posi-
tion. OFF
With the lever in this position, fuel will
not flow. Use this lever position when
performing certain maintenance work
or when storing the vehicle for a pro-
longed time.
EAU13651
KickstarterTo start the engine, fold out the kick-
starter lever, move it down lightly with
your foot until the gears engage, and
then push it down smoothly but force-
fully. This model is equipped with a pri-
mary kickstarter, allowing the engine to
be started in any gear if the clutch is
disengaged. However, shifting the
transmission into the neutral position
before starting is recommended.
1. Arrow mark positioned over “ON”
1
1. Arrow mark positioned over “OFF”
1
1. Kickstarter
1
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INSTRUMENT AND CONTROL FUNCTIONS
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12 Yamaha dealer repair it if it does not
function properly.
EAU59340
Ignition circuit cut-off systemThe ignition circuit cut-off system (com-
prising the sidestand switch, clutch
switch and neutral switch) has the fol-
lowing functions.
It prevents starting when the trans-
mission is in gear and the sides-
tand is up, but the clutch lever is
not pulled.

It prevents starting when the trans-
mission is in gear and the clutch le-
ver is pulled, but the sidestand is
still down.

It cuts the running engine when the
transmission is in gear and the sid-
estand is moved down.
Periodically check the operation of the
ignition circuit cut-off system according
to the following procedure.
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INSTRUMENT AND CONTROL FUNCTIONS
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With the engine turned off:
1. Move the sidestand down.
2. Make sure that the engine stop switch is set to “
3. Turn the key on.
4. Shift the transmission into the neutral position.
5. Push the kick starter lever down.
Does the engine start?
With the engine still running:
6. Move the sidestand up.
7. Keep the clutch lever pulled.
8. Shift the transmission into gear.
9. Move the sidestand down.
Does the engine stall?
After the engine has stalled:
10. Move the sidestand up.
11. Keep the clutch lever pulled.
12. Push the kick starter lever down.
Does the engine start?
The system is OK. The motorcycle can be ridden.
YES NO YES NO YES NO
The neutral switch may not be working correctly.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
The clutch switch may not be working correctly.
The motorcycle should not be ridden until
checked by a Yamaha dealer.The sidestand switch may not be working correctly.
The motorcycle should not be ridden until
checked by a Yamaha dealer.The vehicle must be placed on the center-
stand during this inspection. If a malfunction is noted, have a Yamaha
dealer check the system before riding.
WARNING
”.
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FOR YOUR SAFETY – PRE-OPERATION CHECKS
EAU15598
Inspect your vehicle each time you use it to make sure the vehi cle is in safe operating condition. Always follow the inspection
and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWA11152
Failure to inspect or maintain the vehicle properly increases the possibility of an accident or equipment damage.
Do not operate the vehicle if you find any problem. If a problem cannot be corrected by the procedures provided inthis manual, have the vehicle inspected by a Yamaha dealer.
Before using this vehicle, check the following points:
ITEM CHECKS PAGE
Fuel Check fuel level in fuel tank.
Refuel if necessary.
Check fuel line for leakage.
Check fuel tank breather hose for
obstructions, cracks or damage, and check
hose connection. 3-7, 3-9
Engine oil Check oil level in oil tank.
If necessary, add recommended oil to specified level.
Check vehicle for oil leakage. 6-9
Front brake Check operation.
If soft or spongy, have Yamaha dealer bleed hydraulic system.
Check lever free play.
Adjust if necessary.
Check brake pads for wear.
Replace if necessary.
Check fluid level in reservoir.
If necessary, add specified brake fluid to specified level.
Check hydraulic system for leakage. 6-17, 6-20
Rear brake Check operation.
Check pedal free play.
Adjust if necessary. 6-18, 6-20
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OPERATION AND IMPORTANT RIDING POINTS
EAU15952
Read the Owner’s Manual carefully to
become familiar with all controls. If
there is a control or function you do not
understand, ask your Yamaha dealer.
WARNING
EWA10272
Failure to familiarize yourself with
the controls can lead to loss of con-
trol, which could cause an accidentor injury.
EAU59360
TIPThis model is equipped with:
a lean angle sensor to stop the en-
gine in case of a turnover. In this
case, turn the key to “OFF” and
then to “ON”. Failing to do so will
prevent the engine from starting
even though the engine will crank
when pushing the kick starter lever
down.

an engine auto-stop system. The
engine stops automatically if left
idling for 20 minutes. If the engine
stops, simply push the kick starterlever down to restart the engine.
EAU59530
Starting the engineIn order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:
The transmission is in the neutral
position.

The transmission is in gear with
the clutch lever pulled and the sid-
estand up.
See page 3-13 for more informa-
tion.
1. Turn the key to “ON” and set the engine stop switch to “ ”.
The engine trouble warning light
and fuel level warning light should
come on for a few seconds, then
go off.
NOTICE
ECA16712
If the warning light does not come
on initially when the key is turned to
“ON”, or if the warning light remains
on, see page 3-2 for the warning lightcircuit check.
2. Shift the transmission into the neu- tral position. The neutral indicator
light should come on. If not, ask a
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OPERATION AND IMPORTANT RIDING POINTS
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Yamaha dealer to check the elec-
trical circuit.
3. Completely close the throttle and apply the decompression lever.
4. Slowly push the kickstarter lever down until the starting mark shows
on the kick indicator.
5. Release the decompression lever, release the kickstarter lever, and
then push the kickstarter lever
down forcefully to start the engine.
NOTICE
ECA11043
For maximum engine life, never ac-
celerate hard when the engine iscold!
EAU59470
Starting troubleIf the engine fails to start after 4 to 5
kicks, clear out the combustion cham-
ber with the following procedure.1. Turn the key to “OFF”.
2. While applying the decompression lever, fully open the throttle grip
and push the kickstarter lever
down 4 to 5 times.
3. Turn the key to “ON” and retry starting the engine.
EAU16672
ShiftingShifting gears lets you control the
amount of engine power available for
starting off, accelerating, climbing hills,
etc.
The gear positions are shown in the il-
lustration.TIPTo shift the transmission into the neu-
tral position, press the shift pedal down
repeatedly until it reaches the end of itstravel, and then slightly raise it.
1. Starting mark
2. Kick indicator
2
1
1. Shift pedal
2. Neutral position
1
2
1 3 4 5
N
2
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OPERATION AND IMPORTANT RIDING POINTS
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NOTICE
ECA10261

Even with the transmission in
the neutral position, do not
coast for long periods of time
with the engine off, and do not
tow the motorcycle for long dis-
tances. The transmission is
properly lubricated only when
the engine is running. Inade-
quate lubrication may damage
the transmission.

Always use the clutch while
changing gears to avoid damag-
ing the engine, transmission,
and drive train, which are not
designed to withstand theshock of forced shifting.
EAU16811
Tips for reducing fuel
consumptionFuel consumption depends largely on
your riding style. Consider the following
tips to reduce fuel consumption:
Shift up swiftly, and avoid high en-
gine speeds during acceleration.

Do not rev the engine while shifting
down, and avoid high engine
speeds with no load on the engine.

Turn the engine off instead of let-
ting it idle for an extended length of
time (e.g., in traffic jams, at traffic
lights or at railroad crossings).
EAU16842
Engine break-inThere is never a more important period
in the life of your engine than the period
between 0 and 1600 km (1000 mi). For
this reason, you should read the follow-
ing material carefully.
Since the engine is brand new, do not
put an excessive load on it for the first
1600 km (1000 mi). The various parts in
the engine wear and polish themselves
to the correct operating clearances.
During this period, prolonged full-throt-
tle operation or any condition that might
result in engine overheating must be
avoided.
EAU17094
0–1000 km (0–600 mi)
Avoid prolonged operation above 3500
r/min. NOTICE: After 1000 km (600
mi) of operation, the engine oil must
be changed and the oil filter car-
tridge or element replaced.
[ECA10303]
1000–1600 km (600–1000 mi)
Avoid prolonged operation above 4200
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