2006 YAMAHA YBR125 engine

TABLE OF CONTENTSSAFETY INFORMATION ..................1-1
DESCRIPTION ..................................2-1
Left view ..........................................2-1
Right view ........................................2-2
Controls and instruments.................2-3
INSTRUMENT AND CONTROL
FUNCTIONS.......................................3-1
Main switch/steering lock ................3-1
Indicator lights ................................3-2
Speedometer unit ...........................3-2
Tachometer ....................................3-3
Fuel gauge ......................................3-3
Handlebar switches ........................3-3
Clutch lever .....................................3-4
Shift pedal .......................................3-4
Brake lever .....................................3-5
Brake pedal ....................................3-5
Fuel tank cap ..................................3-5
Fuel .................................................3-6
Catalytic converter ..........................3-7
Fuel cock ........................................3-7
Starter (choke) lever .......................3-8
Kickstarter .......................................3-9
Adjusting the shock absorber
assemblies ..................................3-9
Carrier ...........................................3-10
Luggage strap holders ..................3-10
Starting circuit cut-off system .......3-10PRE-OPERATION CHECKS............. 4-1
Pre-operation check list .................. 4-2
OPERATION AND IMPORTANT
RIDING POINTS................................. 5-1
Starting a cold engine .................... 5-1
Starting a warm engine .................. 5-2
Shifting ........................................... 5-2
Tips for reducing fuel
consumption ............................... 5-3
Engine break-in .............................. 5-3
Parking ........................................... 5-4
PERIODIC MAINTENANCE AND
MINOR REPAIR................................. 6-1
Owner’s tool kit ............................... 6-1
Periodic maintenance and
lubrication chart .......................... 6-2
Removing and installing the
cowling and panels ..................... 6-5
Checking the spark plug ................. 6-8
Engine oil ....................................... 6-9
Cleaning the air filter element ...... 6-11
Adjusting the carburetor ............... 6-12
Adjusting the engine idling
speed ........................................ 6-13
Adjusting the throttle cable free
play ........................................... 6-13
Valve clearance ............................ 6-14
Tires ............................................. 6-14
Cast wheels .................................. 6-16Adjusting the clutch lever
free play .................................... 6-17
Checking the front brake lever
free play .................................... 6-18
Adjusting the brake pedal
free play .................................... 6-18
Adjusting the rear brake light
switch ....................................... 6-19
Checking the front brake pads
and rear brake shoes ............... 6-20
Checking the front brake fluid
level .......................................... 6-20
Changing the brake fluid .............. 6-21
Drive chain slack .......................... 6-22
Cleaning and lubricating the drive
chain ......................................... 6-23
Checking and lubricating the
cables ....................................... 6-24
Checking and lubricating the
throttle grip and cable ............... 6-24
Checking and lubricating the
brake and shift pedals .............. 6-24
Checking and lubricating the
brake and clutch levers ............ 6-25
Checking and lubricating the
centerstand ............................... 6-26
Lubricating the swingarm
pivots ........................................ 6-26
Checking the front fork ................. 6-26
Checking the steering .................. 6-27
Checking the wheel bearings ....... 6-28U3D9E0E0.book Page 1 Saturday, December 25, 2004 11:35 AM

SAFETY INFORMATION
1-2
1 wide on a turn due to EXCESSIVE
SPEED or undercornering (insuffi-
cient lean angle for the speed).
Always obey the speed limit and
never travel faster than warrant-
ed by road and traffic conditions.
Always signal before turning or
changing lanes. Make sure that
other motorists can see you.


The posture of the operator and
passenger is important for proper
control.
The operator should keep both
hands on the handlebar and
both feet on the operator foot-
rests during operation to main-
tain control of the motorcycle.
The passenger should always
hold onto the operator, seat
strap, or grab bar, if equipped,
with both hands and keep both
feet on the passenger footrests.
Never carry a passenger unless
he or she can firmly place both
feet on the passenger footrests.


Never ride under the influence of
alcohol or other drugs.


This motorcycle is designed for on-
road use only, therefore, it is not
suitable for off-road use.
Protective apparel
The majority of fatalities from motor-
cycle accidents are the result of head
injuries. The use of a safety helmet is
the single most critical factor in the pre-
vention or reduction of head injuries.


Always wear an approved helmet.


Wear a face shield or goggles.
Wind in your unprotected eyes
could contribute to an impairment
of vision which could delay seeing
a hazard.


The use of a jacket, heavy boots,
trousers, gloves, etc., is effective in
preventing or reducing abrasions
or lacerations.


Never wear loose-fitting clothes,
otherwise they could catch on the
control levers, footrests, or wheels
and cause injury or an accident.


Never touch the engine or exhaust
system during or after operation.
They become very hot and cancause burns. Always wear protec-
tive clothing that covers your legs,
ankles, and feet.


Passengers should also observe
the precautions mentioned above.
Modifications
Modifications made to this motorcycle
not approved by Yamaha, or the re-
moval of original equipment, may ren-
der the motorcycle unsafe for use and
may cause severe personal injury.
Modifications may also make your
motorcycle illegal to use.
Loading and accessories
Adding accessories or cargo to your
motorcycle can adversely affect stabili-
ty and handling if the weight distribution
of the motorcycle is changed. To avoid
the possibility of an accident, use ex-
treme caution when adding cargo or
accessories to your motorcycle. Use
extra care when riding a motorcycle
that has added cargo or accessories.
Here are some general guidelines to
follow if loading cargo or adding acces-
sories to your motorcycle:
U3D9E0E0.book Page 2 Saturday, December 25, 2004 11:35 AM

SAFETY INFORMATION
1-4
1 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
motorcycle’s electrical system, an
electric failure could result, which
could cause a dangerous loss of
lights or engine power.
Gasoline and exhaust gas


GASOLINE IS HIGHLY FLAMMA-
BLE:
Always turn the engine off when
refueling.
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
motorcycle in an area that has ad-
equate ventilation.


Always turn the engine off before
leaving the motorcycle unattended
and remove the key from the main
switch. When parking the motor-
cycle, note the following:
The engine and exhaust system
may be hot, therefore, park the
motorcycle in a place where pe-
destrians or children are not like-
ly to touch these hot areas.
Do not park the motorcycle on a
slope or soft ground, otherwise it
may fall over.
Do not park the motorcycle near
a flammable source (e.g. a kero-
sene heater, or near an open
flame), otherwise it could catch
fire.


When transporting the motorcycle
in another vehicle, make sure that
it is kept upright and that the fuel
cock is turned to “ON” or “RES” (for
vacuum type) / “OFF” (for manual
type). If it should lean over, gaso-
line may leak out of the carburetor
or fuel tank.


If you should swallow any gaso-
line, inhale a lot of gasoline vapor,
or allow gasoline to get into youreyes, see your doctor immediately.
If any gasoline spills on your skin
or clothing, immediately wash the
affected area with soap and water
and change your clothes.
U3D9E0E0.book Page 4 Saturday, December 25, 2004 11:35 AM

DESCRIPTION
2-1
2
EAU10410
Left view1. Headlight (page 6-31)
2. Fuel cock (page 3-7)
3. Fuse (page 6-30)
4. Battery (page 6-28)
5. Owner’s tool kit (page 6-1)
6. Luggage strap holder (page 3-10)
7. Shock absorber assembly spring preload adjusting ring (page 3-9)
8. Engine oil drain bolt (page 6-9)9. Shift pedal (page 3-4)U3D9E0E0.book Page 1 Saturday, December 25, 2004 11:35 AM

DESCRIPTION
2-2
2
EAU10420
Right view1. Carrier (page 3-10)
2. Air filter element (page 6-11)
3. Engine oil filler cap (page 6-9)
4. Brake pedal (page 3-5)
5. Kickstarter (page 3-9)
6. Shock absorber assembly spring preload adjusting ring (page 3-9)
7. Luggage strap holder (page 3-10)
U3D9E0E0.book Page 2 Saturday, December 25, 2004 11:35 AM

INSTRUMENT AND CONTROL FUNCTIONS
3-1
3
EAU10460
Main switch/steering lock The main switch/steering lock controls
the ignition and lighting systems, and is
used to lock the steering. The various
positions are described below.
EAU33590
ON
All electrical circuits are supplied with
power; the meter lighting, taillight and
auxiliary light come on, and the engine
can be started. The key cannot be re-
moved.NOTE:The headlight comes on automatically
when the engine is started and stays on
until the key is turned to “OFF”, even ifthe engine stalls.
EAU10660
OFF
All electrical systems are off. The key
can be removed.
EAU10680
LOCK
The steering is locked, and all electrical
systems are off. The key can be re-
moved.
To lock the steering1. Turn the handlebars all the way to
the left.
2. Push the key in from the “OFF” po-
sition, and then turn it to “LOCK”
while still pushing it.
3. Remove the key.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”.
1. Push.
2. Turn.
1. Push.
2. Turn.
U3D9E0E0.book Page 1 Saturday, December 25, 2004 11:35 AM

INSTRUMENT AND CONTROL FUNCTIONS
3-3
3
EAU11851
Tachometer The electric tachometer allows the rider
to monitor the engine speed and keep it
within the ideal power range.CAUTION:
ECA10031
Do not operate the engine in the ta-
chometer red zone.Red zone: 10000 r/min and above
EAU37050
Fuel gauge The fuel gauge indicates the amount of
fuel in the fuel tank. The needle moves
towards “E” (Empty) as the fuel level
decreases. When the needle reaches
the red line, approximately 3.0 L (0.79
US gal) (0.66 Imp.gal) remain in the
fuel tank. If this occurs, refuel as soon
as possible.NOTE:

Do not allow the fuel tank to empty
itself completely.


The main switch must be turned to
“ON” for the fuel gauge to displayan accurate fuel level reading.
EAU12343
Handlebar switches Left
Right
1. Tachometer
2. Tachometer red zone
1. Fuel gauge
2. Red line
1. Dimmer switch “/”
2. Turn signal switch “/”
3. Horn switch “”
1. Start switch “”
U3D9E0E0.book Page 3 Saturday, December 25, 2004 11:35 AM

INSTRUMENT AND CONTROL FUNCTIONS
3-4
3
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.
EAU12710
Start switch “”
Push this switch to crank the engine
with the starter.CAUTION:
ECA10050
See page 5-1 for starting instruc-tions prior to starting the engine.
EAU31640
Clutch lever The clutch lever is located at the left
handlebar grip. To disengage the
clutch, pull the lever toward the handle-
bar grip. To engage the clutch, release
the lever. The lever should be pulled
rapidly and released slowly for smooth
clutch operation.
The clutch lever is equipped with a
clutch switch, which is part of the start-
ing circuit cut-off system. (See page
3-10.)
EAU12870
Shift pedal The shift pedal is located on the left
side of the engine and is used in com-
bination with the clutch lever when
shifting the gears of the 5-speed con-
stant-mesh transmission equipped on
this motorcycle.
1. Clutch lever
1. Shift pedal
U3D9E0E0.book Page 4 Saturday, December 25, 2004 11:35 AM