maintenance YAMAHA SR400 2016 User Guide

Periodic maintenance and adjustment
6-6
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14
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
6-7
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EAU59460
Removing and installing the
panel
The panel shown needs to be removed
to perform some of the maintenance
jobs described in this chapter. Refer to
this section each time the panel needs
to be removed and installed.
TIP
The panel on the left side is removable
using the key. However there is no
need to remove this panel for mainte-
nance jobs described in this chapter.
EAU19152Panel A
To remove the panel
Remove the bolt, and then pull the pan-
el off as shown. To install the panel
Place the panel in the original position,
and then install the bolt.
1. Panel A
11. Panel A
2. Bolt
3. Washer
1
2
3
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Periodic maintenance and adjustment
6-8
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8
9
10
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12
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14
EAU19605
Checking the spark plug
The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plug can re-
veal the condition of the engine.
To remove the spark plug 1. Remove the spark plug cap.
2. Remove the spark plug as shown, with the spark plug wrench includ-
ed in the owner’s tool kit.
To check the spark plug 1. Check that the porcelain insulator around the center electrode of the spark plug is a medium-to-light tan
(the ideal color when the vehicle is
ridden normally).
TIP
If the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer check
the vehicle.
2. Check the spark plug for electrode erosion and excessive carbon or
other deposits, and replace it if
necessary.
3. Measure the spark plug gap with a wire thickness gauge and, if nec-
essary, adjust the gap to specifica-
tion.
To install the spark plug 1. Clean the surface of the spark plug gasket and its mating surface, and
then wipe off any grime from the
spark plug threads.
2. Install the spark plug with the spark
1. Spark plug cap
1. Spark plug wrench
1
1
Specified spark plug: NGK/BPR6ES
1. Spark plug gap
Spark plug gap:0.7–0.8 mm (0.028–0.031 in)
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Periodic maintenance and adjustment
6-9
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14
plug wrench, and then tighten it to
the specified torque.
TIP
If a torque wrench is not available when
installing a spark plug, a good estimate
of the correct torque is 1/4–1/2 turn
past finger tight. However, the spark
plug should be tightened to the speci-
fied torque as soon as possible.
3. Install the spark plug cap.
EAU59626
Engine oil and oil filter
element
The engine oil level should be checked
before each ride. In addition, the oil
must be changed and the oil filter ele-
ment replaced at the intervals specified
in the periodic maintenance and lubri-
cation chart.
To check the engine oil level1. Start the engine, warm it up for several minutes, and then turn it
off.
2. On a level surface, place the vehi- cle on the centerstand.
3. Wait a few minutes until the oil set- tles. Remove the engine oil filler
cap, wipe the dipstick clean, insert
it back into the oil filler hole (with-
out screwing it in), and then re-
move it again to check the oil level.
WARNING! Never remove the
engine oil filler cap after high-
speed operation, otherwise hot
engine oil could spout out and
cause damage or injury. Always
let the engine oil cool down suf-
ficiently before removing the oil
filler cap.
[EWA17640]
TIP
The engine oil should be between the
minimum and maximum level marks.
Tightening torque:Spark plug:25 Nm (2.5 m·kgf, 18 ft·lbf)
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Periodic maintenance and adjustment
6-10
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6
7
8
9
10
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12
13
14 4. If the engine oil is below the mini-
mum level mark, add sufficient oil
of the recommended type to raise
it to the correct level.
5. Install the oil filler cap.
To change the engine oil (with or
without oil filter element replace-
ment) 1. Start the engine, warm it up for several minutes, and then turn it
off.
2. Place an oil pan under the engine to collect the used oil.
3. Remove the oil filter element cover bleed bolt and its gasket, and the
oil filter element drain bolt to drain
the oil from the oil filter element
chamber. 4. Remove the engine oil drain bolt
and its gasket to drain the oil from
the crankcase.
5. Remove the engine oil filler cap, the engine oil tank drain bolt and
its gasket to drain the oil from the
oil tank.
1. Engine oil filler cap
2. Dipstick
3. Maximum level mark
4. Minimum level mark
3
4
1
2
1. Oil filter element cover bleed bolt
2. Gasket
3. Oil filter element drain bolt
1. Gasket
2. Engine oil drain bolt (crankcase)
1
2
3
21
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Periodic maintenance and adjustment
6-11
1
2
3
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5
6
7
8
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12
13
14
TIP
Skip steps 6–8 if the oil filter element is
not being replaced. 6. Remove the oil filter element cover by removing the bolts.
7. Remove and replace the oil filter element and O-rings.
TIP
Make sure that the O-rings are properly
seated. 8. Install the oil filter element cover by
installing the bolts, and then tight-
en the bolts to the specified torque.
9. Install the oil filter element drain bolt, and then tighten the bolt to the
specified torque.
10. Install the oil filter element cover bleed bolt and its gasket, and then
tighten the bolt to the specified
torque.
11. Install the engine oil drain bolts and their new gasket, and then
tighten the bolts to the specified
torques.
1. Engine oil drain bolt (oil tank)
2. Gasket
1. Oil filter element cover bolt
21
1
1. Oil filter element cover
2. O-ring
3. Oil filter element
Tightening torque:Oil filter element cover bolt: 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Tightening torque: Oil filter element drain bolt: 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Tightening torque: Oil filter element cover bleed bolt: 5 Nm (0.5 m·kgf, 3.6 ft·lbf)
2
1
3
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Periodic maintenance and adjustment
6-12
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14 12. Add the specified amount of the
recommended engine oil, and then
install and tighten the oil filler cap.
TIP
Be sure to wipe off spilled oil on any
parts after the engine and exhaust sys-
tem have cooled down.
NOTICE
ECA11621
In order to prevent clutch slip-
page (since the engine oil also
lubricates the clutch), do not
mix any chemical additives. Do
not use oils with a diesel speci-
fication of “CD” or oils of a high-
er quality than specified. In
addition, do not use oils labeled
“ENERGY CONSERVING II” or
higher.
Make sure that no foreign mate-
rial enters the crankcase.
13. Start the engine, and then let it idle for several minutes while checking
it for oil leakage. If oil is leaking, im-
mediately turn the engine off and
check for the cause.
14. Turn the engine off, and then check the oil level and correct it if necessary.
NOTICE
ECA11232
After changing the engine oil, make
sure to check the oil pressure as de-
scribed below.
Loosen the bleed bolt.
Start the engine and keep it
idling until oil flows out. If no oil
comes out after one minute,
turn the engine off immediately
so it will not seize. If this occurs,
have a Yamaha dealer repair the
vehicle.
After checking the oil pressure,
tighten the bleed bolt to the
specified torque.
Tightening torques:
Engine oil drain bolt (crankcase):
30 Nm (3.0 m·kgf, 22 ft·lbf)
Engine oil drain bolt (oil tank): 16 Nm (1.6 m·kgf, 12 ft·lbf)
Recommended engine oil: See page 8-1.
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)
1. Bleed bolt
Tightening torque:Bleed bolt:
18 Nm (1.8 m·kgf, 13 ft·lbf)
1
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Periodic maintenance and adjustment
6-13
1
2
3
4
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6
7
8
9
10
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14
EAU52031
Replacing the air filter element
The air filter element should be re-
placed at the intervals specified in the
periodic maintenance and lubrication
chart. Replace the air filter element
more frequently if you are riding in un-
usually wet or dusty areas.
To replace the air filter element 1. Remove panel A. (See page 6-7.)
2. Remove the air filter case cover by removing the screws.
3. Pull the air filter element out.
4. Insert a new air filter element into the air filter case. NOTICE: Make
sure that the air filter element is
properly seated in the air filter
case. The engine should never
be operated without the air filter element installed, otherwise the
piston(s) and/or cylinder(s) may
become excessively worn.[ECA10482]
5. Install the air filter case cover by in-
stalling the screws.
6. Install the panel.
1. Screw
2. Air filter case cover
1. Air filter element
1
2
1
1
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Periodic maintenance and adjustment
6-14
1
2
3
4
5
6
7
8
9
10
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14
EAU44735
Checking the engine idling
speed
Check the engine idling speed and, if
necessary, have it corrected by a
Yamaha dealer.
EAU21386
Checking the throttle grip free
play
Measure the throttle grip free play as
shown.
Periodically check the throttle grip free
play and, if necessary, have a Yamaha
dealer adjust it.
Engine idling speed: 1200–1400 r/min
1. Throttle grip free play
Throttle grip free play:3.0–5.0 mm (0.12–0.20 in)
1
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Periodic maintenance and adjustment
6-15
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2
3
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6
7
8
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EAU21402
Valve clearance
The valve clearance changes with use,
resulting in improper air-fuel mixture
and/or engine noise. To prevent this
from occurring, the valve clearance
must be adjusted by a Yamaha dealer
at the intervals specified in the periodic
maintenance and lubrication chart.
EAU70280
Tires
Tires are the only contact between the
vehicle and the road. Safety in all con-
ditions of riding depends on a relatively
small area of road contact. Therefore, it
is essential to maintain the tires in good
condition at all times and replace them
at the appropriate time with the speci-
fied tires.
Tire air pressure
The tire air pressure should be checked
and, if necessary, adjusted before each
ride.
WARNING
EWA10504
Operation of this vehicle with im-
proper tire pressure may cause se-
vere injury or death from loss of
control.
The tire air pressure must be
checked and adjusted on cold
tires (i.e., when the temperature
of the tires equals the ambient
temperature).
The tire air pressure must be ad-
justed in accordance with the
riding speed and with the total
weight of rider, passenger, car-
go, and accessories approved
for this model.
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