check engine YAMAHA SR400 2016 User Guide

Periodic maintenance and adjustment
6-5
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13 Drive chain Check chain slack, alignment
and condition.
Adjust and lubricate chain with a special O-ring chain lubricant
thoroughly. Every 500 km (300 mi) and after
washing the motorcycle, riding
in the rain or riding in wet areas
14 *Steering bearings Check bearing play and
steering for roughness. 
Lubricate with lithium-soap- based grease. Every 20000 km (12000 mi)
15 *Chassis fasteners Make sure that all nuts, bolts
and screws are properly
tightened. 
16 Brake lever pivot
shaft Lubricate with silicone grease.

17 Brake pedal pivot
shaft Lubricate with lithium-soap-
based grease. 
18 Clutch lever pivot
shaft Lubricate with lithium-soap-
based grease. 
19 Sidestand,
centerstand Check operation.
Lubricate with lithium-soap-
based grease. 
20 *Sidestand switch Check operation. 
21 *Front fork Check operation and for oil
leakage. 
22 *Shock absorber
assemblies Check operation and shock
absorbers for oil leakage. 
23 Engine oil Change.
Check oil level and vehicle for
oil leakage. 
24 Engine oil filter
element Replace.

25 *Front and rear
brake switches Check operation.

26 Moving parts and
cables Lubricate.

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
6-8
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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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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
6-12
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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
6-14
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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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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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Periodic maintenance and adjustment
6-26
1
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7
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13
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
6-43
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2
3
4
5
6
7
8
9
10
11
12
13
14
EAU67930
Troubleshooting chart
1. FuelThere is enough fuel.
There is no fuel.Supply fuel.
Check the battery.
The turn signal
flashes brightly.
The turn signal does
not flash or is weak.
The engine does not
start.
Check the battery.
Wipe off with a dry
cloth and correct the
spark plug gap, or
replace the spark
plug.
Check the battery
lead connections,
and have a Yamaha
dealer charge the
battery if necessary.
Operate the
kickstarter.
If the engine does
not start, check the
ignition.
2. BatteryThe battery is good.
3. IgnitionWet
Dry
There is compression.
There is no
compression.
Operate the
kickstarter.
The engine does not start.
Have a Yamaha dealer check the vehicle.
Have a Yamaha dealer check the vehicle.
The engine does not
start.
Check the
compression.Have a Yamaha
dealer check the
vehicle.
Remove the spark
plug and check
the electrodes.
With the key in the on
position, operate the
turn signal switch.
Operate the
kickstarter.
Check the fuel level
in the fuel tank.
4. Compression
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Motorcycle care and storage
7-4
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2
3
4
5
6
7
8
9
10
11
12
13
14
EAU43204
Storage
Short-term
Always store your motorcycle in a cool,
dry place and, if necessary, protect it
against dust with a porous cover. Be
sure the engine and the exhaust sys-
tem are cool before covering the motor-
cycle.
NOTICE
ECA10811
Storing the motorcycle in a
poorly ventilated room or cover-
ing it with a tarp, while it is still
wet, will allow water and humid-
ity to seep in and cause rust.
To prevent corrosion, avoid
damp cellars, stables (because
of the presence of ammonia)
and areas where strong chemi-
cals are stored.
Long-term
Before storing your motorcycle for sev-
eral months: 1. Follow all the instructions in the “Care” section of this chapter.
2. Fill up the fuel tank and add fuel stabilizer (if available) to prevent
the fuel tank from rusting and the
fuel from deteriorating.
3. Perform the following steps to pro- tect the cylinder, piston rings, etc.
from corrosion.
a. Remove the spark plug cap and spark plug.
b. Pour a teaspoonful of engine oil into the spark plug bore.
c. Install the spark plug cap onto the spark plug, and then place
the spark plug on the cylinder head so that the electrodes are
grounded. (This will limit spark-
ing during the next step.)
d. Turn the engine over several
times with the starter. (This will
coat the cylinder wall with oil.)
WARNING! To prevent dam-
age or injury from sparking,
make sure to ground the
spark plug electrodes while
turning the engine
over.
[EWA10952]
e. Remove the spark plug capfrom the spark plug, and then
install the spark plug and the
spark plug cap.
4. Lubricate all control cables and the pivoting points of all levers and
pedals as well as of the sides-
tand/centerstand.
5. Check and, if necessary, correct the tire air pressure, and then lift
the motorcycle so that both of its
wheels are off the ground. Alterna-
tively, turn the wheels a little every
month in order to prevent the tires
from becoming degraded in one
spot.
6. Cover the muffler outlet with a plastic bag to prevent moisture
from entering it.
7. Remove the battery and fully charge it. Store it in a cool, dry
place and charge it once a month.
Do not store the battery in an ex-
cessively cold or warm place [less
than 0  C (30 F) or more than 30
 C (90 F)]. For more information
on storing the battery, see page
6-31.
TIP
Make any necessary repairs before
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10-1
1
2
3
4
5
6
7
8
9
10
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12
13
14
Index
A
Air filter element, replacing ................... 6-13
Auxiliary light bulb, replacing ................ 6-36
B
Battery................................................... 6-31
Brake and clutch levers, checking and lubricating ........................................... 6-28
Brake fluid, changing ............................ 6-24
Brake fluid level, checking .................... 6-23
Brake lever .............................................. 3-7
Brake lever free play, adjusting............. 6-19
Brake light switches .............................. 6-22
Brake pads and shoes, checking .......... 6-22
Brake pedal ............................................. 3-7
Brake pedal, checking and
lubricating ........................................... 6-28
Brake pedal height and free play,
adjusting ............................................. 6-20
C
Cables, checking and lubricating .......... 6-27
Care ........................................................ 7-1
Catalytic converter ................................ 3-11
Centerstand and sidestand, checking and lubricating .................................... 6-29
Clutch lever ............................................. 3-6
Clutch lever free play, adjusting ............ 6-18
D
Decompression lever ............................ 3-12
Dimmer switch ........................................ 3-5
Drive chain, cleaning and lubricating .... 6-26
Drive chain slack ................................... 6-25
E
Engine break-in ....................................... 5-5
Engine idling speed, checking .............. 6-14
Engine oil and oil filter element ............... 6-9
Engine serial number .............................. 9-1
Engine stop switch .................................. 3-5
Engine trouble warning light.................... 3-3
F
Front fork, checking .............................. 6-30
Fuel ......................................................... 3-9
Fuel cock............................................... 3-11
Fuel consumption, tips for reducing ........ 5-5
Fuel level warning light ........................... 3-2
Fuel tank breather/overflow hose.......... 3-10
Fuel tank cap .......................................... 3-8
Fuses, replacing.................................... 6-33
H
Handlebar switches................................. 3-4
Hazard switch ......................................... 3-5 Headlight bulb, replacing ...................... 6-35
High beam indicator light ........................ 3-2
Horn switch ............................................. 3-5
I
Identification numbers ............................ 9-1
Ignition circuit cut-off system ................ 3-15
Indicator lights and warning lights .......... 3-2
K
Kickstarter ............................................ 3-12
M
Main switch/steering lock ....................... 3-1
Maintenance and lubrication, periodic .... 6-4
Maintenance, emission control system... 6-3
Matte color, caution ................................ 7-1
Model label ............................................. 9-2
N
Neutral indicator light .............................. 3-2
P
Panel, removing and installing ............... 6-7
Parking ................................................... 5-6
Part locations .......................................... 2-1
Pass switch ............................................ 3-5
S
Safety information .................................. 1-1
Seat ...................................................... 3-13
Shifting ................................................... 5-3
Shift pedal .............................................. 3-6
Shift pedal, chec
king ............................ 6-21
Shock absorber assemblies, adjusting ............................................. 3-13
Sidestand ............................................. 3-14
Spark plug, checking .............................. 6-8
Specifications ......................................... 8-1
Speedometer unit ................................... 3-3
Starting the engine ................................. 5-2
Starting the engine, trouble .................... 5-3
Steering, checking ................................ 6-30
Storage ................................................... 7-4
Swingarm pivots, lubricating ................. 6-29
T
Tachometer ............................................ 3-4
Tail/brake light bulb, replacing .............. 6-37
Throttle grip and cable, checking and
lubricating ........................................... 6-27
Throttle grip free play, checking ........... 6-14
Tires ..................................................... 6-15
Tool kit .................................................... 6-2
Troubleshooting .................................... 6-42
Troubleshooting chart ........................... 6-43
Turn signal indicator light ....................... 3-2
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