2016 YAMAHA SR400 engine

Table of contents
Safety information............................ 1-1
Description ........................................ 2-1
Left view .......................................... 2-1
Right view ........................................ 2-2
Controls and instruments ................ 2-3
Instrument and control functions ... 3-1
Main switch/steering lock ................ 3-1
Indicator lights and warning lights ... 3-2
Speedometer unit ..... ....................... 3-3
Tachometer ..................................... 3-4
Handlebar switches ......................... 3-4
Clutch lever ..................................... 3-6
Shift pedal ....................................... 3-6
Brake lever ...................................... 3-7
Brake pedal .............. ....................... 3-7
Fuel tank cap ................................... 3-8
Fuel ................................................. 3-9
Fuel tank breather/overflow hose ........................................... 3-10
Catalytic converter......................... 3-11
Fuel cock ....................................... 3-11
Kickstarter .... ............................. .... 3-12
Decompression lever..................... 3-12
Seat ............................................... 3-13
Adjusting the shock absorber assemblies ................................. 3-13
Sidestand ...................................... 3-14
Ignition circuit cut- off system ......... 3-15
For your safety – pre-operation
checks ................................................ 4-1
Operation and im portant riding
points ................................................. 5-1
Starting the engine .......................... 5-2
Starting trouble ................................ 5-3
Shifting ............................................ 5-3
Tips for reducing fuel consumption................................. 5-5
Engine break-in ............................... 5-5
Parking ............................................ 5-6 Periodic maintenance and
adjustment
........................................ 6-1
Owner’s tool kit ............................... 6-2
Periodic maintenance chart for the
emission control system .............. 6-3
General maintenance and lubrication chart ........................... 6-4
Removing and installing the panel ............................................ 6-7
Checking the spark plug ................. 6-8
Engine oil and oil filter element ....... 6-9
Replacing the air filter element ..... 6-13
Checking the engine idling
speed ......................................... 6-14
Checking the throttle grip free play ............................................ 6-14
Valve clearance ............................ 6-15
Tires .............................................. 6-15
Spoke wheels........... ..................... 6-17
Adjusting the clutch lever free play ............................................ 6-18
Adjusting the brake lever free play ............................................ 6-19
Adjusting the brake pedal height
and free play .............................. 6-20
Checking the shift pedal................ 6-21
Brake light switches ...................... 6-22
Checking the front brake pads and rear brake shoes ................ 6-22
Checking the brake fluid level ....... 6-23
Changing the brake fluid .............. 6-24
Drive chain slack ........................... 6-25
Cleaning and lubricating the drive
chain .......................................... 6-26
Checking and lubricating the cables ........................................ 6-27
Checking and lubricating the throttle grip and ca ble ................ 6-27
Checking and lubricating the
brake and clutch levers.............. 6-28
Checking and lubricating the brake pedal ................................ 6-28
Checking and lubricating the centerstand and sidestand ........ 6-29
Lubricating the swingarm pivots.... 6-29
Checking the front fork .................. 6-30
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Safety information
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14 help you to avoid an accident.
We recommend that you prac- tice riding your motorcycle
where there is no traffic until you
have become thoroughly famil-
iar with the motorcycle and all of
its controls.
Many accidents have been caused
by error of the motorcycle opera-
tor. A typical error made by the op-
erator is veering wide on a turn due
to excessive speed or undercor-
nering (insufficient lean angle for
the speed). Always obey the speed limit and never travel faster than warrant-
ed by road and traffic conditions.
Always signal before turning or changing lanes. Make sure that
other motorists can see you.
The posture of the operator and
passenger is important for proper
control. The operator should keep both hands on the handlebar and
both feet on the operator foot-
rests during operation to main-
tain control of the motorcycle.
The passenger should always hold onto the operator, the seat
strap or grab bar, if equipped,
with both hands and keep both
feet on the passenger footrests.
Never carry a passenger unless
he or she can firmly place both
feet on the passenger footrests.
Never ride under the influence of
alcohol or other drugs.
This motorcycle is designed for on-
road use only. It is not suitable for
off-road use. Protective Apparel
The majority of fatalities from motorcy-
cle accidents are the result of head in-
juries. The use of a safety helmet is the
single most critical factor in the preven-
tion or reduction of head injuries.
Always wear an approved helmet.
Wear a face shield or goggles.
Wind in your unprotected eyes
could contribute to an impairment
of vision that could delay seeing a
hazard.
The use of a jacket, heavy boots,
trousers, gloves, etc., is effective in
preventing or reducing abrasions
or lacerations.
Never wear loose-fitting clothes,
otherwise they could catch on the
control levers, footrests, or wheels
and cause injury or an accident.
Always wear protective clothing
that covers your legs, ankles, and
feet. The engine or exhaust sys-
tem become very hot during or af-
ter operation and can cause burns.
A passenger should also observe
the above precautions.
Avoid Carbon Monoxide Poisoning
All engine exhaust contains carbon
monoxide, a deadly gas. Breathing car-
bon monoxide can cause headaches,
dizziness, drowsiness, nausea, confu-
sion, and eventually death.
Carbon Monoxide is a colorless, odor-
less, tasteless gas which may be pres-
ent even if you do not see or smell any
engine exhaust. Deadly levels of car-
bon monoxide can collect rapidly and
you can quickly be overcome and un-
able to save yourself. Also, deadly lev-
els of carbon monoxide can linger for
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Safety information
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hours or days in enclosed or poorly
ventilated areas. If you experience any
symptoms of carbon monoxide poison-
ing, leave the area immediately, get
fresh air, and SEEK MEDICAL TREAT-
MENT.
Do not run engine indoors. Even if
you try to ventilate engine exhaust
with fans or open windows and
doors, carbon monoxide can rap-
idly reach dangerous levels.
Do not run engine in poorly venti-
lated or partially enclosed areas
such as barns, garages, or car-
ports.
Do not run engine outdoors where
engine exhaust can be drawn into
a building through openings such
as windows and doors.
Loading
Adding accessories or cargo to your
motorcycle can adversely affect stabili-
ty and handling if the weight distribution
of the motorcycle is changed. To avoid
the possibility of an accident, use ex-
treme caution when adding cargo or
accessories to your motorcycle. Use
extra care when riding a motorcycle
that has added cargo or accessories.
Here, along with the information about
accessories below, are some general
guidelines to follow if loading cargo to
your motorcycle:
The total weight of the operator, pas-
senger, accessories and cargo must
not exceed the maximum load limit.
Operation of an overloaded vehicle
could cause an accident. When loading within this weight limit,
keep the following in mind:
Cargo and accessory weight
should be kept as low and close to
the motorcycle as possible. Se-
curely pack your heaviest items as
close to the center of the vehicle as
possible and make sure to distrib-
ute the weight as evenly as possi-
ble on both sides of the motorcycle
to minimize imbalance or instabili-
ty.
Shifting weights can create a sud-
den imbalance. Make sure that ac-
cessories and cargo are securely
attached to the motorcycle before
riding. Check accessory mounts
and cargo restraints frequently.
Properly adjust the suspension for your load (suspension-ad-
justable models only), and
check the condition and pres-
sure of your tires.
Never attach any large or heavy items to the handlebar, front
fork, or front fender. These
items, including such cargo as
sleeping bags, duffel bags, or
tents, can create unstable han-
dling or a slow steering re-
sponse.
This vehicle is not designed to
pull a trailer or to be attached to
a sidecar.
Genuine Yamaha Accessories
Choosing accessories for your vehicle
is an important decision. Genuine
Yamaha accessories, which are avail-
able only from a Yamaha dealer, have
been designed, tested, and approved
by Yamaha for use on your vehicle.
Maximum load: 150 kg (331 lb)
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Safety information
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14 Many companies with no connection to
Yamaha manufacture parts and acces-
sories or offer other modifications for
Yamaha vehicles. Yamaha is not in a
position to test the products that these
aftermarket companies produce.
Therefore, Yamaha can neither en-
dorse nor recommend the use of ac-
cessories not sold by Yamaha or
modifications not specifically recom-
mended by Yamaha, even if sold and
installed by a Yamaha dealer.
Aftermarket Parts, Accessories,
and Modifications
While you may find aftermarket prod-
ucts similar in design and quality to
genuine Yamaha accessories, recog-
nize that some aftermarket accessories
or modifications are not suitable be-
cause of potential safety hazards to you
or others. Installing aftermarket prod-
ucts or having other modifications per-
formed to your vehicle that change any
of the vehicle’s design or operation
characteristics can put you and others
at greater risk of serious injury or death.
You are responsible for injuries related
to changes in the vehicle.
Keep the following guidelines in mind,
as well as those provided under “Load-
ing” when mounting accessories.
Never install accessories or carry
cargo that would impair the perfor-
mance of your motorcycle. Care-
fully inspect the accessory before
using it to make sure that it does
not in any way reduce ground
clearance or cornering clearance,
limit suspension travel, steering
travel or control operation, or ob-
scure lights or reflectors. Accessories fitted to the handle-
bar or the front fork area can cre-
ate instability due to improper
weight distribution or aerody-
namic changes. If accessories
are added to the handlebar or
front fork area, they must be as
lightweight as possible and
should be kept to a minimum.
Bulky or large accessories may seriously affect the stability of
the motorcycle due to aerody-
namic effects. Wind may at-
tempt to lift the motorcycle, or
the motorcycle may become un-
stable in cross winds. These ac-
cessories may also cause
instability when passing or being
passed by large vehicles.
Certain accessories can dis- place the operator from his or
her normal riding position. This
improper position limits the free-
dom of movement of the opera-
tor and may limit control ability,
therefore, such accessories are
not recommended.
Use caution when adding electrical
accessories. If electrical accesso-
ries exceed the capacity of the mo-
torcycle’s electrical system, an
electric failure could result, which
could cause a dangerous loss of
lights or engine power.
Aftermarket Tires and Rims
The tires and rims that came with your
motorcycle were designed to match the
performance capabilities and to provide
the best combination of handling, brak-
ing, and comfort. Other tires, rims, siz-
es, and combinations may not be
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Description
EAU63371
Left view
1. Engine oil dipstick (page 6-9)
2. Engine oil filler cap (page 6-9)
3. Fuel tank cap (page 3-8)
4. Fuel cock (page 3-11)
5. Battery (page 6-31)
6. Fuse (page 6-33)
7. Shock absorber assembly spring preload adjusting ring (page 3-13)
8. Shift pedal (page 3-6)
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5, 63
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Instrument and control functions
EAU10462
Main switch/steering lock
The main switch/steering lock controls
the ignition and lighting systems, and is
used to lock the steering. The various
positions are described below.
EAU45111ON
All electrical circuits are supplied with
power, and the meter lighting and tail-
light come on, and the engine can be
started. The key cannot be removed.
TIP
The headlight comes on automatically
when the engine is started and stays on
until the key is turned to “OFF”, even if
the engine stalls.
EAU10662OFF
All electrical systems are off. The key
can be removed.
WARNING
EWA10062
Never turn the key to “OFF” or
“LOCK” while the vehicle is moving.
Otherwise the electrical systems will
be switched off, which may result in
loss of control or an accident.
EAU10687LOCK
The steering is locked and all electrical
systems are off. The key can be re-
moved.
To lock the steering
1. Turn the handlebars all the way to the left.
2. With the key in the “OFF” position, push the key in and turn it to
“LOCK”.
3. Remove the key.
TIP
If the steering will not lock, try turning
the handlebars back to the right slightly.
To unlock the steering
P
ON
OFF
LOCK
1. Push.
2. Turn.
1. Push.
2. Turn.
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Instrument and control functions
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14 1. Insert the key.
2. With the key in the “LOCK” posi-
tion, push the key in and turn it to
“OFF”.
EAU59680 (Parking)
The hazard lights and turn signal lights
can be turned on, but all other electrical
systems are off. The key can be re-
moved.
The steering must be locked before the
key can be turned to “ ”.
NOTICE
ECA20760
Using the hazard or turn signal
lights for an extended length of time
may cause the battery to discharge.
EAU49398
Indicator light s and warning
lights
EAU11022Turn signal indicator light “ ”
This indicator light flashes when a turn
signal light is flashing.
EAU11061Neutral indicator light “ ”
This indicator light comes on when the
transmission is in the neutral position.
EAU11081High beam indicator light “ ”
This indicator light comes on when the
high beam of the headlight is switched
on.
EAU11354Fuel level warning light “ ”
This warning light comes on when the
fuel level drops below approximately
2.2 L (0.58 US gal, 0.48 Imp.gal). When
this occurs, refuel as soon as possible.
The electrical circuit of the warning light
can be checked by turning the key to
“ON”. The warning light should come
on for a few seconds, and then go off.
1. Engine trouble warning light “ ”
2. Fuel level warning light “ ”
3. Neutral indicator light “ ”
4. High beam indicator light “ ”
5. Turn signal indicator light “ ”
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Instrument and control functions
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If the warning light does not come on
initially when the key is turned to “ON”,
or if the warning light remains on, have
a Yamaha dealer check the electrical
circuit.
EAU11486Engine trouble warning light “ ”
This warning light comes on if a prob-
lem is detected in the electrical circuit
monitoring the engine. If this occurs,
have a Yamaha dealer check the vehi-
cle.
The electrical circuit of the warning light
can be checked by turning the key to
“ON”. The warning light should come
on for a few seconds, and then go off.
If the warning light does not come on
initially when the key is turned to “ON”,
or if the warning light remains on, have
a Yamaha dealer check the electrical
circuit.
EAU11631
Speedometer unit
The speedometer unit is equipped with
a speedometer, an odometer and a
tripmeter. The speedometer shows rid-
ing speed. The odometer shows the to-
tal distance traveled. The tripmeter
shows the distance traveled since it
was last set to zero with the reset knob.
The tripmeter can be used to estimate
the distance that can be traveled with a
full tank of fuel. This information will en-
able you to plan future fuel stops.
1. Reset knob
2. Speedometer
3. Odometer
4. Tripmeter
123 4
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