SAFETY INFORMATION
1-4
1
Take care not to spill any gaso-
line on the engine or exhaust
system when refueling.
Never refuel while smoking or in
the vicinity of an open flame.
Never start the engine or let it run
for any length of time in a closed
area. The exhaust fumes are poi-
sonous and may cause loss of
consciousness and death within a
short time. Always operate your
scooter in an area that has ade-
quate ventilation.
Always turn the engine off before
leaving the scooter unattended
and remove the key from the main
switch. When parking the scooter,
note the following:
The engine and exhaust system
may be hot, therefore, park the
scooter in a place where pedes-
trians or children are not likely to
touch these hot areas.
Do not park the scooter on a
slope or soft ground, otherwise it
may fall over.
Do not park the scooter near a
flammable source (e.g., a kero-sene heater, or near an open
flame), otherwise it could catch
fire.
If you should swallow any gaso-
line, inhale a lot of gasoline vapor,
or allow gasoline to get into your
eyes, see your doctor immediate-
ly. If any gasoline spills on your
skin or clothing, immediately wash
the affected area with soap and
water and change your clothes.
EAU10371
Further safe-riding points
Be sure to signal clearly when
making turns.
Braking can be extremely difficult
on a wet road. Avoid hard braking,
because the scooter could slide.
Apply the brakes slowly when
stopping on a wet surface.
Slow down as you approach a cor-
ner or turn. Once you have com-
pleted a turn, accelerate slowly.
Be careful when passing parked
cars. A driver might not see you
and open a door in your path.
Railroad crossings, streetcar rails,
iron plates on road construction
sites, and manhole covers be-
come extremely slippery when
wet. Slow down and cross them
with caution. Keep the scooter up-
right, otherwise it could slide out
from under you.
The brake pads could get wet
when you wash the scooter. After
washing the scooter, check the
brakes before riding.
Always wear a helmet, gloves,
trousers (tapered around the cuff
INSTRUMENT AND CONTROL FUNCTIONS
3-3
2
34
5
6
7
8
9
To unlock the steering
Push the key in, and then turn it to
“OFF” while still pushing it.
WARNING
EWA10060
Never turn the key to “OFF” or
“LOCK” while the vehicle is moving,
otherwise the electrical systems will
be switched off, which may result in
loss of control or an accident. Make
sure that the vehicle is stopped be-
fore turning the key to “OFF” or
“LOCK”.
EAU10941
(Parking)
The steering is locked, and the taillight,
license plate light and auxiliary lights
are on. The hazard lights and turn sig-
nal lights can be turned on, but all other
electrical systems are off. The key can
be removed.
The steering must be locked before the
key can be turned to “ ”.
CAUTION:
ECA11020
Do not use the parking position for
an extended length of time, other-
wise the battery may discharge.
EAU11003
Indicator and warning lights
EAU11030
Turn signal indicator lights “” and
“”
The corresponding indicator light flash-
es when the turn signal switch is
pushed to the left or right.
EAU11080
High beam indicator light “”
This indicator light comes on when the
1. Turn signal indicator lights “ ” and “ ”
2. High beam indicator light “ ”
3. Immobilizer system indicator light
4. Engine trouble warning light “ ”
5. Anti-lock Brake System (ABS) warning
light “ ” (for ABS models)
123
4
5
ABS
INSTRUMENT AND CONTROL FUNCTIONS
3-10
1
2
3
4
5
6
7
8
9Right
EAU12360
Pass switch “PASS”
Press this switch to flash the headlight.
EAU12400
Dimmer switch “/”
Set this switch to “” for the high
beam and to “” for the low beam.
EAU12460
Turn signal switch “/”
To signal a right-hand turn, push this
switch to “”. To signal a left-hand
turn, push this switch to “”. When re-leased, the switch returns to the center
position. To cancel the turn signal
lights, push the switch in after it has re-
turned to the center position.
EAU12500
Horn switch “”
Press this switch to sound the horn.
EAU12660
Engine stop switch “/”
Set this switch to “” before starting
the engine. Set this switch to “” to
stop the engine in case of an emergen-
cy, such as when the vehicle overturns
or when the throttle cable is stuck.
EAU12720
Start switch “”
With the sidestand up, push this switch
while applying the front or rear brake to
crank the engine with the starter.
CAUTION:
ECA10050
See page 5-1 for starting instruc-
tions prior to starting the engine.
EAU42810
(for ABS models)
The engine trouble warning light and
ABS warning light will come on when
the key is turned to “ON” and the start
switch is pushed, but this does not indi-
cate a malfunction.
EAU12733
Hazard switch “”
With the key in the “ON” or “” posi-
tion, use this switch to turn on the haz-
ard lights (simultaneous flashing of all
turn signal lights).
The hazard lights are used in case of
an emergency or to warn other drivers
when your vehicle is stopped where it
might be a traffic hazard.
CAUTION:
ECA10061
Do not use the hazard lights for an
extended length of time with the en-
gine not running, otherwise the bat-
tery may discharge.
1. Engine stop switch “/”
2. Hazard switch “”
3. Start switch “”
1
2
3
5-1
2
3
4
56
7
8
9
OPERATION AND IMPORTANT RIDING POINTS
EAU15980
WARNING
EWA10870
Become thoroughly familiar
with all operating controls and
their functions before riding.
Consult a Yamaha dealer re-
garding any control or function
that you do not thoroughly un-
derstand.
Never start the engine or oper-
ate it in a closed area for any
length of time. Exhaust fumes
are poisonous, and inhaling
them can cause loss of con-
sciousness and death within a
short time. Always make sure
that there is adequate ventila-
tion.
For safety, always start the en-
gine with the centerstand down.
EAU34460
Starting the engine
CAUTION:
ECA10250
See page 5-4 for engine break-in in-
structions prior to operating the ve-
hicle for the first time.
In order for the ignition circuit cut-off
system to enable starting, the side-
stand must be up.
WARNING
EWA10290
Before starting the engine,
check the function of the igni-
tion circuit cut-off system ac-
cording to the procedure
described on page 3-20.
Never ride with the sidestand
down.
1. Turn the key to “ON” and make
sure that the engine stop switch is
set to “”.
2. Close the throttle completely.
3. Start the engine by pushing the
start switch while applying the front
or rear brake.
NOTE:
If the engine does not start, release thestart switch, wait a few seconds, and
then try again. Each starting attempt
should be as short as possible to pre-
serve the battery. Do not crank the en-
gine more than 10 seconds on any one
attempt.
CAUTION:
ECA11040
For maximum engine life, never ac-
celerate hard when the engine is
cold!
OPERATION AND IMPORTANT RIDING POINTS
5-3
2
3
4
56
7
8
9 Rear
WARNING
EWA10300
Avoid braking hard or suddenly
(especially when leaning over to
one side), otherwise the scooter
may skid or overturn.
Railroad crossings, streetcar
rails, iron plates on road con-
struction sites, and manhole
covers become extremely slip-
pery when wet. Therefore, slow
down when approaching such
areas and cross them with cau-
tion.
Keep in mind that braking on a
wet road is much more difficult.
Ride slowly down a hill, as brak-ing downhill can be very diffi-
cult.
EAU16820
Tips for reducing fuel
consumption
Fuel consumption depends largely on
your riding style. Consider the following
tips to reduce fuel consumption:
Avoid high engine speeds during
acceleration.
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).
PERIODIC MAINTENANCE AND MINOR REPAIR
6-26
1
2
3
4
5
6
7
8
9
EAU33473
Adjusting the rear brake lock
lever cable
Rear brake lock lever cable adjustment
may be required if the rear brake lock
lever does not hold properly. When the
rear brake lock lever is not in use, the
rear brake lock lever cable length
should measure 45 mm to 47 mm (1.77
in to 1.85 in) at the rear brake caliper.
Periodically check the rear brake lock
lever cable length and, if necessary,
adjust it as follows.
To increase the rear brake lock lever
cable length, turn the adjusting nut at
the rear brake caliper in direction (a).To decrease the rear brake lock lever
cable length, turn the adjusting nut in
direction (b).
WARNING
EWA10650
If proper adjustment cannot be ob-
tained as described, have a Yamaha
dealer make this adjustment.
EAU22390
Checking the front and rear
brake pads
The front and rear brake pads must be
checked for wear at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
EAU22430
Front brake pads
Each front brake pad is provided with
wear indicator grooves, which allow
you to check the brake pad wear with-
out having to disassemble the brake.
To check the brake pad wear, check
the wear indicator grooves. If a brake
pad has worn to the point that the wear
1. Adjusting nut
2. Rear brake lock lever cable length
1
2
(b) (a)
1. Wear indicator groove
11
8-1
1
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3
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9
SPECIFICATIONS
EAU2633M
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:
SAE 10W-30, SAE 10W-40, SAE 15W-40,
SAE 20W-40 or SAE 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:
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:
Manufacturer:
AISAN
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