Page 31 of 92

INSTRUMENT AND CONTROL FUNCTIONS
3-15
3 brand. Use of unleaded fuel will extend
spark plug life and reduce mainte-
nance costs.
Gasohol
There are two types of gasohol: gaso-
hol containing ethanol and that con-
taining methanol. Gasohol containing
ethanol can be used if the ethanol con-
tent does not exceed 10% (E10). Gas-
ohol containing methanol is not
recommended by Yamaha because it
can cause damage to the fuel system
or vehicle performance problems.
EAU13446
Catalytic convertersThis vehicle is equipped with catalytic
converters in the exhaust system.
WARNING
EWA10863
The exhaust system is hot after op-
eration. To prevent a fire hazard or
burns:
Do not park the vehicle near
possible fire hazards such as
grass or other materials that
easily burn.
Park the vehicle in a place
where pedestrians or children
are not likely to touch the hot
exhaust system.
Make sure that the exhaust sys-
tem has cooled down before
doing any maintenance work.
Do not allow the engine to idle
more than a few minutes. Long
idling can cause a build-up of
heat.
NOTICE
ECA10702
Use only unleaded gasoline. The use
of leaded gasoline will cause unre-
pairable damage to the catalytic
converter.
U1SDE1E0.book Page 15 Monday, September 23, 2013 3:55 PM
Page 56 of 92

PERIODIC MAINTENANCE AND ADJUSTMENT
6-13
6
EAUM3031
Engine oil and oil filter ele-
mentThe 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 and when the oil change
indicator comes on.
To check the engine oil level
1. Place the vehicle on the center-
stand. A slight tilt to the side can
result in a false reading.
2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Wait a few minutes until the oil set-
tles, remove the oil filler cap, wipe
the dipstick clean, insert it back
into the oil filler hole (without
screwing it in), and then remove it
again to check the oil level.TIPThe engine oil should be between the
tip of the dipstick and the maximum
level mark.
4. If the engine oil is not between the
tip of the dipstick and the maxi-
mum level mark, add sufficient oil
of the recommended type to raise
it to the correct level.
5. Insert the dipstick into the oil filler
hole, and then tighten the oil filler
cap.
To change the engine oil (with or
without oil filter element replace-
ment)
1. Place the vehicle on the center-
stand.2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Place an oil pan under the engine
to collect the used oil.
4. Remove the engine oil filler cap,
the engine oil drain bolt and its
gasket to drain the oil from the
crankcase.
TIPSkip steps 5…7 if the oil filter element is
not being replaced.5. Remove the oil filter element cover
by removing the bolts. NOTICE:
When removing the oil filter ele-
ment cover, the compression
1. Engine oil filler cap
2. Dipstick
3. Maximum level mark
4. Tip of the engine oil dipstickZAUM102834
1
2
1. Engine oil drain bolt
2. Gasket
12
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Page 78 of 92

PERIODIC MAINTENANCE AND ADJUSTMENT
6-35
6
EAU54501
Auxiliary lightThis model is equipped with LED-type
auxiliary lights.
If an auxiliary light does not come on,
have a Yamaha dealer check it.
EAU25882
TroubleshootingAlthough Yamaha scooters receive a
thorough inspection before shipment
from the factory, trouble may occur
during operation. Any problem in the
fuel, compression, or ignition systems,
for example, can cause poor starting
and loss of power.
The following troubleshooting charts
represent quick and easy procedures
for checking these vital systems your-
self. However, should your scooter re-
quire any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the scooter prop-
erly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, 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 waterheaters or furnaces. Gasoline or
gasoline vapors can ignite or ex-
plode, causing severe injury or prop-
erty damage.
U1SDE1E0.book Page 35 Monday, September 23, 2013 3:55 PM
Page 85 of 92

SPECIFICATIONS
8-1
8
Dimensions:Overall length:
2190 mm (86.2 in)
Overall width:
780 mm (30.7 in)
Overall height:
1385 mm (54.5 in)
Seat height:
785 mm (30.9 in)
Wheelbase:
1565 mm (61.6 in)
Ground clearance:
103 mm (4.06 in)
Minimum turning radius:
2500 mm (98.4 in)Weight:Curb weight:
YP400R 211 kg (465 lb)
YP400RA 215 kg (474 lb)Engine:Engine type:
Liquid cooled 4-stroke, DOHC
Cylinder arrangement:
Single cylinder
Displacement:
395 cm³
Bore × stroke:
83.0 × 73.0 mm (3.27 × 2.87 in)
Compression ratio:
10.60 : 1
Starting system:
Electric starter
Lubrication system:
Wet sump
Engine oil:Recommended brand:
YAMALUBE
Type:
SAE 10W-30, 10W-40, 10W-50, 15W-40,
20W-40 or 20W-50
Recommended engine oil grade:
API service SG type or higher, JASO
standard MA
Engine oil quantity:
Without oil filter element replacement:
1.50 L (1.59 US qt, 1.32 Imp.qt)
With oil filter element replacement:
1.70 L (1.80 US qt, 1.50 Imp.qt)Final transmission oil:Type:
YAMALUBE 10W-40 or SAE 10W-30 type
SE motor oil
Quantity:
0.25 L (0.26 US qt, 0.22 Imp.qt)
Cooling system:Coolant reservoir capacity (up to the
maximum level mark):
0.31 L (0.33 US qt, 0.27 Imp.qt)
Radiator capacity (including all routes):
1.38 L (1.46 US qt, 1.21 Imp.qt)Air filter:Air filter element:
Oil-coated paper elementFuel:Recommended fuel:
Premium unleaded gasoline (Gasohol (E10)
acceptable)
Fuel tank capacity:
14.0 L (3.70 US gal, 3.08 Imp.gal)
Fuel reserve amount:
2.0 L (0.53 US gal, 0.44 Imp.gal)Fuel injection:Throttle body:
ID mark:
5RUG 20Spark plug(s):Manufacturer/model:
NGK/CR7E
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)Clutch:Clutch type:
Dry, centrifugal automaticTransmission:Primary reduction ratio:
1.000
Final drive:
Gear
–20 –10 0
1020 30 40 50 C 10 30 50 70 90 110 0 130 F
SAE 10W-30
SAE 15W-40SAE 20W-40SAE 20W-50
SAE 10W-40SAE 10W-50
U1SDE1E0.book Page 1 Monday, September 23, 2013 3:55 PM