2016 YAMAHA SR400 check engine

Operation and important riding points
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EAU16811
Tips for reducing fuel
consumption
Fuel 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-in
There 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
r/min.
1600 km (1000 mi) and beyond
The vehicle can now be operated nor-
mally.
NOTICE
ECA10311
Keep the engine speed out of
the tachometer red zone.
If any engine trouble should oc-
cur during the engine break-in
period, immediately have a
Yamaha dealer check the vehi-
cle.
2RD-28199-E1.book 5 ページ ２０１５年９月３日　木曜日　午後３時４２分

Periodic maintenance and adjustment
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EAU46862
TIP
The annual checks must be performed every year, except if a kilometer-
based maintenance, or for the UK, a mileage-based maintenance, is per-
formed instead.
From 50000 km (30000 mi), repeat the maintenance intervals starting from
10000 km (6000 mi).
Items marked with an asterisk should be performed by a Yamaha dealer as
they require special tools, data and technical skills.
EAU63321
Periodic maintenance chart for the emission control system
NO. ITEM
1 *Fuel line Check fuel hoses for cracks or
damage. 
2 Spark plug Check condition.
Clean and regap.

Replace. 
3 *Valves Check valve clearance.
Adjust. 
4 *Fuel injection Check engine idle speed. 
5 *Muffler and
exhaust pipe Check the screw clamp(s) for
looseness. 
6 *Air induction
system Check the air cut-off valve, reed
valve, and hose for damage.
Replace any damaged parts if necessary. 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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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
2RD-28199-E1.book 5 ページ ２０１５年９月３日　木曜日　午後３時４２分

Periodic maintenance and adjustment
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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
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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
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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
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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
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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.
2RD-28199-E1.book 15 ページ ２０１５年９月３日　木曜日　午後３時４２分