INSTRUMENT AND CONTROL FUNCTIONS
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9fuel may deteriorate painted surfac-
es or plastic parts.
EAU33520
CAUTION:
ECA11400
Use only unleaded gasoline. The use
of leaded gasoline will cause severe
damage to internal engine parts,
such as the valves and piston rings,
as well as to the exhaust system.
Your Yamaha engine has been de-
signed to use regular unleaded gaso-
line with a research octane number of
91 or higher. If knocking (or pinging) oc-
curs, use a gasoline of a different brand
or premium unleaded fuel. Use of un-
leaded fuel will extend spark plug life
and reduce maintenance costs.
EAU13441
Catalytic converter
This vehicle is equipped with catalytic
converters in the exhaust system.
WARNING
EWA10860
The exhaust system is hot after op-
eration. Make sure that the exhaust
system has cooled down before do-
ing any maintenance work.
CAUTION:
ECA10700
The following precautions must be
observed to prevent a fire hazard or
other damages.
Use only unleaded gasoline.
The use of leaded gasoline will
cause unrepairable damage to
the catalytic converter.
Never park the vehicle near pos-
sible fire hazards such as grass
or other materials that easily
burn.
Do not allow the engine to idle
too long.
EAU34140
Seats
Rider seat
To open the rider seat
1. Place the scooter on the center-
stand.
2. Insert the key into the main switch,
and then turn it counterclockwise.
Recommended fuel:
REGULAR UNLEADED GASOLINE
ONLY
Fuel tank capacity:
14.0 L (3.70 US gal) (3.08 Imp.gal)
1. Rider seat
2. Passenger seat
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SPECIFICATIONS
EAU2633H
Dimensions:
Overall length:
2230 mm (87.8 in)
Overall width:
780 mm (30.7 in)
Overall height:
1380 mm (54.3 in)
Seat height:
760 mm (29.9 in)
Wheelbase:
1565 mm (61.6 in)
Ground clearance:
120 mm (4.72 in)
Minimum turning radius:
2600 mm (102.4 in)
Weight:
With oil and fuel:
YP400 219.0 kg (483 lb)
YP400A 223.0 kg (492 lb)
Engine:
Engine type:
Liquid cooled 4-stroke, DOHC
Cylinder arrangement:
Forward-inclined single cylinder
Displacement:
395.0 cm
3
Bore
×
stroke:
83.0
×
73.0 mm (3.27
×
2.87 in)
Compression ratio:
10.60 :1Starting system:
Electric starter
Lubrication system:
Wet sump
Engine oil:
Type:
SAE10W30, SAE10W40, SAE15W40,
SAE20W40 or SAE20W50
Recommended engine oil grade:
API service SG type or higher, JASO stan-
dard 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:
SAE10W30 type SE motor oil
Quantity:
0.25 L (0.26 US qt) (0.22 Imp.qt)
Cooling system:
Coolant reservoir capacity (up to the maxi-
mum level mark):
0.32 L (0.34 US qt) (0.28 Imp.qt)
Radiator capacity (including all routes):
1.57 L (1.66 US qt) (1.38 Imp.qt)
Air filter:
Air filter element:
Oil-coated paper element
Fuel:
Recommended fuel:
Regular unleaded gasoline only
Fuel tank capacity:
14.0 L (3.70 US gal) (3.08 Imp.gal)
Fuel injector:
Manufacturer:
AISAN
Model/quantity:
1100-87H90
Spark plug (s):
Manufacturer/model:
NGK/CR7E
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
Clutch:
Clutch type:
Dry, centrifugal automatic
Transmission:
Primary reduction system:
Helical gear
Primary reduction ratio:
31/14 (2.214)
-20 -10 0
10 20 30
40
50 ˚C
SAE 10W-30
SAE 15W-40SAE 20W-40SAE 20W-50
SAE 10W-40
