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SAFETY INFORMATION
genuine Yamaha accessories, recog-
nize that some aftermarket accessories
or modifications are not suitable be-
cause of potential safety hazards to you
or others. Installing aftermarket prod-
ucts or having other modifications per-
formed to your vehicle that change any
of the vehicle’s design or operation
characteristics can put you and others
at greater risk of serious injury or death.
You are responsible for injuries related
to changes in the vehicle.
Keep the following guidelines in mind,
as well as those provided under “Load-
ing” when mounting accessories.
Never install accessories or carry
cargo that would impair the perfor-
mance of your scooter. Carefully
inspect the accessory before using
it to make sure that it does not in
any way reduce ground clearance
or cornering clearance, limit sus-
pension travel, steering travel or
control operation, or obscure lights
or reflectors.
• Accessories fitted to the handle-
bar or the front fork area can
create instability due to improperweight distribution or aerody-
namic changes. If accessories
are added to the handlebar or
front fork area, they must be as
lightweight as possible and
should be kept to a minimum.
• Bulky or large accessories may
seriously affect the stability of
the scooter due to aerodynamic
effects. Wind may attempt to lift
the scooter, or the scooter may
become unstable in cross
winds. These accessories may
also cause instability when
passing or being passed by
large vehicles.
• Certain accessories can dis-
place the operator from his or
her normal riding position. This
improper position limits the free-
dom of movement of the opera-
tor and may limit control ability,
therefore, such accessories are
not recommended.
Use caution when adding electri-
cal accessories. If electrical acces-
sories exceed the capacity of the
scooter’s electrical system, anelectric failure could result, which
could cause a dangerous loss of
lights or engine power.
Aftermarket Tires and Rims
The tires and rims that came with your
scooter were designed to match the
performance capabilities and to provide
the best combination of handling, brak-
ing, and comfort. Other tires, rims, siz-
es, and combinations may not be
appropriate. Refer to page 6-21 for tire
specifications and more information on
replacing your tires.
Transporting the Scooter
Be sure to observe following instruc-
tions before transporting the scooter in
another vehicle.
Remove all loose items from the
scooter.
Point the front wheel straight
ahead on the trailer or in the truck
bed, and choke it in a rail to pre-
vent movement.
Secure the scooter with tie-downs
or suitable straps that are attached
to solid parts of the scooter, such
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OPERATION AND IMPORTANT RIDING POINTS
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EAU16841
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.
EAU34321
0–1000 km (0–600 mi)
Avoid prolonged operation above
4000 r/min.
NOTICE:
After 1000 km
(600 mi) of operation, be sure to re-
place the engine oil, final transmis-
sion oil and the oil filter
element.
[ECA12931]
1000–1600 km (600–1000 mi)
Avoid prolonged operation above6000 r/min.
1600 km (1000 mi) and beyond
The vehicle can now be operated nor-
mally.
NOTICE
ECA10310
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.
EAU17213
Parking
When parking, stop the engine, and
then remove the key from the main
switch.
WARNING
EWA10311
Since the engine and exhaust
system can become very hot,
park in a place where pedestri-
ans or children are not likely to
touch them and be burned.
Do not park on a slope or on soft
ground, otherwise the vehicle
may overturn, increasing the
risk of a fuel leak and fire.
Do not park near grass or other
flammable materials which
might catch fire.
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SPECIFICATIONS
EAU2633Z
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:
Curb weight:
YP400 220 kg (485 lb)
YP400A 223 kg (492 lb)
Engine:
Engine type:
Liquid cooled 4-stroke, DOHC
Cylinder arrangement:
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 ratio:
1.000
Final drive:
Gear
Secondary reduction ratio:
6.643 (31/14 x 42/14)
-20 -10 0
10 20 30
40
50 ˚C
SAE 10W-30
SAE 15W-40SAE 20W-40SAE 20W-50
SAE 10W-40SAE 10W-50
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