2016 YAMAHA SR400 service

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Periodic maintenance and adjustment
EAU17246
Periodic inspection, adjustment, and lu-
brication will keep your vehicle in the
safest and most efficient condition pos-
sible. Safety is an obl igation of the vehi-
cle owner/operator. The most important
points of vehicle inspection, adjust-
ment, and lubrication are explained on
the following pages.
The intervals given in the periodic
maintenance charts should be simply
considered as a general guide under
normal riding conditions. However, de-
pending on the weather, terrain, geo-
graphical location, and individual use,
the maintenance intervals may need to
be shortened.
WARNING
EWA10322
Failure to properly maintain the ve-
hicle or performing maintenance ac-
tivities incorrectly may increase
your risk of injury or death during
service or while using the vehicle. If
you are not familiar with vehicle ser-
vice, have a Yamaha dealer perform
service.
WARNING
EWA15123
Turn off the engine when performing
maintenance unless otherwise
specified.
A running engine has moving
parts that can catch on body
parts or clothing and electrical
parts that can cause shocks or
fires.
Running the engine while ser-
vicing can lead to eye injury,
burns, fire, or carbon monoxide
poisoning – possibly leading to death. See page 1-2 for more in-
formation about carbon monox-
ide.
WARNING
EWA15461
Brake discs, calipers, drums, and
linings can become very hot during
use. To avoid possible burns, let
brake components cool before
touching them.
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Periodic maintenance and adjustment
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EAU17303
Emission controls not only function to
ensure cleaner air, but are also vital to
proper engine operation and maximum
performance. In the following periodic
maintenance charts, the services relat-
ed to emissions control are grouped
separately. These services require
specialized data, knowledge, and
equipment. Maintenance, replacement,
or repair of the emission control devic-
es and systems may be performed by
any repair establishment or individual
that is certified (if applicable). Yamaha
dealers are trained and equipped to
perform these particular services.
EAU59370
Owner’s tool kit
The owner’s tool kit is located inside the
tool box.
To access the owner’s tool kit, slide the
lock cover open, insert the key into the
lock, and then turn it 1/4 turn clockwise.
The service information included in this
manual and the tools provided in the
owner’s tool kit are intended to assist
you in the performance of preventive
maintenance and minor repairs. How-
ever, additional tools such as a torque
wrench may be necessary to perform
certain maintenance work correctly.
TIP
If you do not have the tools or experi-
ence required for a particular job, have
a Yamaha dealer perform it for you.
1. Unlock.
2. Lock cover
1. Owner’s tool kit
1 2
1
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EAU59350
TIP
Air filter This model’s air intake system is equipped with a disposable oil-coated pa- per element. The air filter element cannot be cleaned with compressed air,
it must be replaced.
The air filter element needs to be replaced more frequently when riding in unusually wet or dusty areas.
Hydraulic brake service After disassembling the brake master cylinder and caliper, always change the fluid. Regularly check the brake fluid level and fill the reservoir as re-
quired.
Every two years replace the internal components of the brake master cylin- der and caliper, and change the brake fluid.
Replace the brake hose every four years and if cracked or damaged.
27 *Throttle grip Check operation.
Check throttle grip free play,
and adjust if necessary.
Lubricate cable and grip housing. 
28 *Lights, signals and
switches Check operation.
Adjust headlight beam.

NO. ITEM
X 1000 km
CHECK OR
MAINTENANCE JOB
X 1000 mi
ODOMETER READINGS
ANNUAL CHECK
110203040
0.66121824
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Periodic maintenance and adjustment
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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
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EAU25852
Troubleshooting
Although Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur dur-
ing operation. Any problem in the fuel,
compression, or ignition systems, for
example, can cause poor starting and
loss of power.
The following troubleshooting chart
represents a quick and easy procedure
for checking these vital systems your-
self. However, should your motorcycle
require any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the motorcycle
properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look like
Yamaha parts, but they are often inferi-
or, have a shorter service life and can
lead to expensive repair bills.
WARNING
EWA15142
When checking the fuel system, do
not smoke, and make sure there are
no open flames or sparks in the ar-
ea, including pilot lights from water
heaters or furnaces. Gasoline or
gasoline vapors can ignite or ex-
plode, causing severe injury or
property damage.
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Specifications
EAU69993Dimensions:
Overall length: 2085 mm (82.1 in)
Overall width: 750 mm (29.5 in)
Overall height:
1095 mm (43.1 in)
Seat height: 785 mm (30.9 in)
Wheelbase: 1410 mm (55.5 in)
Ground clearance:
130 mm (5.12 in)
Minimum turning radius: 2.4 m (7.87 ft)
Weight:
Curb weight:
174 kg (384 lb)
Engine:
Combustion cycle:4-stroke
Cooling system:
Air cooled
Valve train: SOHC
Number of cylinders: Single cylinder
Displacement:
399 cm
3
Bore  stroke:
87.0  67.2 mm (3.43  2.65 in)
Compression ratio: 8.5 : 1
Starting system:
Kickstarter
Lubrication system: Dry sump
Engine oil:
Recommended brand:
YAMALUBE
SAE viscosity grades: 10W-40
Recommended engine oil grade:
API service SG type or higher, JASO stan-
dard MA
Engine oil quantity:
Oil change:2.00 L (2.11 US qt, 1.76 Imp.qt)
With oil filter removal:
2.10 L (2.22 US qt, 1.85 Imp.qt)
Air filter:
Air filter element:Oil-coated paper element
Fuel:
Recommended fuel:
Regular unleaded gasoline (Gasohol [E10]
acceptable)
Fuel tank capacity:
12 L (3.2 US gal, 2.6 Imp.gal)
Fuel reserve amount: 2.2 L (0.58 US gal, 0.48 Imp.gal)
Fuel injection:
Throttle body:
ID mark: 2RD1 00
Spark plug(s):
Manufacturer/model:NGK/BPR6ES
Spark plug gap: 0.7–0.8 mm (0.028–0.031 in)
Clutch:
Clutch type:Wet, multiple-disc
Drivetrain:
Primary reduction ratio:
2.567 (77/30)
Final drive: Chain
Secondary reduction ratio: 2.947 (56/19)
Transmission type:
Constant mesh 5-speed
Gear ratio: 1st:
2.357 (33/14)
2nd: 1.556 (28/18)
3rd: 1.190 (25/21)
4th: 0.917 (22/24)
5th: 0.778 (21/27)
Chassis:
Frame type:Semi double cradle
Caster angle: 27.7 
Trail:
111 mm (4.4 in)
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