2008 YAMAHA YBR125 ECU

SAFETY INFORMATION
1-3
1Loading
The total weight of the operator, pas-
senger, accessories and cargo must
not exceed the maximum load limit.
When loading within this weight limit,
keep the following in mind:

Cargo and accessory weight
should be kept as low and close to
the motorcycle as possible. Make
sure to distribute the weight as
evenly as possible on both sides of
the motorcycle to minimize imbal-
ance or instability.


Shifting weights can create a sud-
den imbalance. Make sure that ac-
cessories and cargo are securely
attached to the motorcycle before
riding. Check accessory mounts
and cargo restraints frequently.


Never attach any large or heavy
items to the handlebar, front fork,
or front fender. These items, in-
cluding such cargo as sleepingbags, duffel bags, or tents, can
create unstable handling or a slow
steering response.
Accessories
Genuine Yamaha accessories have
been specifically designed for use on
this motorcycle. Since Yamaha cannot
test all other accessories that may be
available, you must personally be re-
sponsible for the proper selection, in-
stallation and use of non-Yamaha
accessories. Use extreme caution
when selecting and installing any ac-
cessories.
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 motorcycle. Care-
fully inspect the accessory before
using it to make sure that it does
not in any way reduce ground
clearance or cornering clearance,limit suspension travel, steering
travel or control operation, or ob-
scure lights or reflectors.
Accessories fitted to the handle-
bar or the front fork area can
create instability due to improper
weight 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 motorcycle due to aerody-
namic effects. Wind may at-
tempt to lift the motorcycle, or
the motorcycle may become un-
stable in cross winds. These ac-
cessories 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-
Maximum load:
190 kg (419 lb)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-6
6
EAU18771
Removing and installing pan-
els The panels shown need to be removed
to perform some of the maintenance
jobs described in this chapter. Refer to
this section each time a panel needs to
be removed and installed.
EAU36961
Panel A
To remove the panel1. Slide the panel lock cover open, in-
sert the key into the lock, and then
turn it 1/4 turn clockwise.2. Pull the front of the panel out with
the key inserted in the lock, and
then slide the panel forward to re-
lease it in the rear.
To install the panel
1. Secure the rear of the panel, and
then push the front of the panel in
with the key inserted in the lock.
1. Panel A
1
1. Panel B
1. Panel lock cover
2. Unlock.
1
1
2
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-7
6 2. While pushing the panel inward,
turn the key counterclockwise to
the original position, remove it, and
then close the panel lock cover.
EAU37070
Panel B
To remove the panel1. Remove the screw.
2. Pull the front of the panel out, and
then slide the panel forward to re-
lease it in the rear.To install the panel
1. Secure the rear of the panel, and
then push the front of the panel in.
2. Install the screw.
EAU19603
Checking the spark plug The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic mainte-
nance and lubrication chart. In addition,
the condition of the spark plug can re-
veal the condition of the engine.
To remove the spark plug
1. Remove the spark plug cap.
2. Remove the spark plug as shown,
with the spark plug wrench includ-
ed in the owner’s tool kit.
1. Screw
1
1. Spark plug cap
11
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-14
6
WARNING
EWA11020
Because loading has an enormous
impact on the handling, braking,
performance and safety characteris-
tics of your motorcycle, you should
keep the following precautions in
mind.

NEVER OVERLOAD THE
MOTORCYCLE! Operation of an
overloaded motorcycle may re-
sult in tire damage, loss of con-
trol, or severe injury. Make sure
that the total weight of rider,passenger, cargo, and accesso-
ries does not exceed the speci-
fied maximum load for the
vehicle.


Do not carry along loosely
packed items, which can shift
during a ride.


Securely pack the heaviest
items close to the center of the
motorcycle and distribute the
weight evenly on both sides.


Adjust the suspension and tire
air pressure with regard to the
load.


Check the tire condition and airpressure before each ride.Tire inspection
The tires must be checked before each
ride. If the center tread depth reaches
the specified limit, if the tire has a nail or
glass fragments in it, or if the sidewall is
cracked, have a Yamaha dealer re-
place the tire immediately.
NOTE:The tire tread depth limits may differ
from country to country. Always complywith the local regulations.
Tire air pressure (measured on cold
tires):
0–90 kg (0–198 lb):
Front:
175 kPa (1.75 kgf/cm², 25 psi)
Rear:
200 kPa (2.00 kgf/cm², 29 psi)
90–190 kg (198–419 lb):
Front:
175 kPa (1.75 kgf/cm², 25 psi)
Rear:
280 kPa (2.80 kgf/cm², 41 psi)
Maximum load*:
190 kg (419 lb)
* Total weight of rider, passenger, car-
go and accessories
1. Tire sidewall
2. Tire tread depthMinimum tire tread depth (front and
rear):
1.6 mm (0.06 in)
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-25
6
EAUM1650
Lubricating the swingarm piv-
ots The swingarm pivots must be lubricat-
ed at the intervals specified in the peri-
odic maintenance and lubrication chart.
EAU23271
Checking the front fork The condition and operation of the front
fork must be checked as follows at the
intervals specified in the periodic main-
tenance and lubrication chart.
To check the condition
WARNING
EWA10750
Securely support the vehicle so thatthere is no danger of it falling over.
Check the inner tubes for scratches,
damage and excessive oil leakage.
To check the operation
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion.
2. While applying the front brake,
push down hard on the handlebars
several times to check if the front
fork compresses and rebounds
smoothly.
CAUTION:
ECA10590
If any damage is found or the front
fork does not operate smoothly,
have a Yamaha dealer check or re-pair it.
Recommended lubricant:
Lithium-soap-based grease
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-26
6
EAU23280
Checking the steering Worn or loose steering bearings may
cause danger. Therefore, the operation
of the steering must be checked as fol-
lows at the intervals specified in the pe-
riodic maintenance and lubrication
chart.
1. Place a stand under the engine to
raise the front wheel off the
ground.
WARNING
EWA10750
Securely support the vehicle so thatthere is no danger of it falling over.
2. Hold the lower ends of the front
fork legs and try to move them for-
ward and backward. If any free
play can be felt, have a Yamaha
dealer check or repair the steering.
EAU23290
Checking the wheel bearings The front and rear wheel bearings must
be checked at the intervals specified in
the periodic maintenance and lubrica-
tion chart. If there is play in the wheel
hub or if the wheel does not turn
smoothly, have a Yamaha dealer check
the wheel bearings.
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-32
63. Remove the defective bulb by pull-
ing it out.
4. Insert a new bulb into the socket.
5. Install the socket (together with the
bulb) by pushing it in.
6. Install the headlight unit by install-
ing the screws.
EAU24360
Front wheel
EAU37041
To remove the front wheel
WARNING
EWA10820


It is advisable to have a Yamaha
dealer service the wheel.


Securely support the motor-
cycle so that there is no dangerof it falling over.
1. Place the motorcycle on the cen-
terstand.
2. Disconnect the speedometer ca-
ble from the front wheel.3. Remove the rubber caps from the
ends of the wheel axle by pulling
them off.
4. Remove the axle nut and the
washer.
1. Auxiliary light bulb socket
1. Auxiliary light bulb
1. Speedometer cable
1. Rubber cap
2. Axle nut
3. Washer
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PERIODIC MAINTENANCE AND MINOR REPAIR
6-34
66. While applying the front brake,
push down hard on the handlebars
several times to check if the front
fork compresses and rebounds
smoothly.
7. Connect the speedometer cable.
EAU25080
Rear wheel
EAU37180
To remove the rear wheel
WARNING
EWA10820


It is advisable to have a Yamaha
dealer service the wheel.


Securely support the motor-
cycle so that there is no dangerof it falling over.
1. Loosen the axle nut and the brake
torque rod nut at the brake shoe
plate.
2. Disconnect the brake torque rod
from the brake shoe plate by re-
moving the cotter pin, the nut, and
the bolt.3. Place the motorcycle on the cen-
terstand.
4. Remove the brake pedal free play
adjusting nut, and then disconnect
the brake rod from the brake cam-
shaft lever.
1. Axle nut
2. Brake torque rod
3. Brake torque rod cotter pin
4. Brake torque rod nut and bolt
32 1
4
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