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PERIODIC MAINTENANCE AND ADJUSTMENT
6-13
2
3
4
5
67
8
9
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.
TIP
Skip 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
spring will fall out. Take care not
to lose the compression
spring.
[ECA12911]
6. Remove and replace the oil filter
element and O-rings.
1. Engine oil filler cap
2. Dipstick
3. Maximum level mark
4. Tip of the engine oil dipstick
34
1
2
1. Engine oil drain bolt
2. Gasket
12
1. Bolt
2. Oil filter element cover
21
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8-1
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3
4
5
6
7
89
SPECIFICATIONS
EAU2633X
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 220.0 kg (485 lb)
YP400A 223.0 kg (492 lb)
Engine:
Engine type:
Liquid cooled 4-stroke, DOHC
Cylinder arrangement:
Forward-inclined single cylinder
Displacement:
395 cm
3
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 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:
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 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 injection:
Throttle body:
ID mark:
5RUG 20
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)
Secondary reduction system:
Helical gear
-20 -10 0
10 20 30
40
50 ˚C
SAE 10W-30
SAE 15W-40SAE 20W-40SAE 20W-50
SAE 10W-40SAE 10W-50
Page 88 of 94

SPECIFICATIONS
8-2
1
2
3
4
5
6
7
8
9
Secondary reduction ratio:
42/14 (3.000)
Transmission type:
V-belt automatic
Operation:
Centrifugal automatic type
Chassis:
Frame type:
Aluminum die-cast and steel tube back-
bone
Caster angle:
27.00 °
Trail:
100.0 mm (3.94 in)
Front tire:
Type:
Tubeless
Size:
120/80-14M/C 58S
Manufacturer/model:
IRC/MB67
Manufacturer/model:
DUNLOP/D305FL
Rear tire:
Type:
Tubeless
Size:
150/70-13M/C 64S
Manufacturer/model:
IRC/MB67
Manufacturer/model:
DUNLOP/D305L
Loading:
Maximum load:
YP400 188 kg (414 lb)
YP400A 185 kg (408 lb)
* (Total weight of rider, passenger, cargo
and accessories)
Tire air pressure (measured on cold
tires):
Loading condition:
0–90 kg (0–198 lb)
Front:
200 kPa (2.00 kgf/cm
2
, 29 psi)
Rear:
250 kPa (2.50 kgf/cm
2
, 36 psi)
Loading condition:
YP400 90–188 kg (198–414 lb)
YP400A 90–185 kg (198–408 lb)
Front:
200 kPa (2.00 kgf/cm
2
, 29 psi)
Rear:
250 kPa (2.50 kgf/cm
2
, 36 psi)
Front wheel:
Wheel type:
Cast wheel
Rim size:
14M/C x MT3.00
Rear wheel:
Wheel type:
Cast wheel
Rim size:
13M/C x MT4.00
Front brake:
Type:
Dual disc brakeOperation:
Right hand operation
Recommended fluid:
DOT 4
Rear brake:
Type:
Single disc brake
Operation:
Left hand operation
Recommended fluid:
DOT 4
Front suspension:
Type:
Telescopic fork
Spring/shock absorber type:
Coil spring/oil damper
Wheel travel:
120.0 mm (4.72 in)
Rear suspension:
Type:
Unit swing
Spring/shock absorber type:
Coil spring/oil damper
Wheel travel:
104.0 mm (4.09 in)
Electrical system:
Ignition system:
TCI (digital)
Charging system:
AC magneto
Battery:
Model:
GT9B-4