check engine YAMAHA YBR125 2003 User Guide

Torque specifications
Use a torque wrench to tighten these items. It is
recommended that these items be checked occasionally,
specially before a long trip. Always check the tightness of
these items whenever they are loosened for any reason.
!
Torque
Nm
kgf.m Item
Spark plug
Engine oil drain plug
Oil check bolt
Front wheel axle nut
Rear wheel axle nut
12,5
20
7
59
911,25
2,0
0,7
5,9
9,1
A
(Nut)
10 mm
12 mm
14 mm
17 mm
19 mm
22 mmB
(Bolt)
6 mm
8 mm
10 mm
12 mm
14 mm
16 mmGeneral torque especifications
Nm
6
15
30
55
85
130kgf.m
0,6
1,5
3,0
5,5
8,5
13,0lbf. ft
4,3
11
22
40
61
94
lbf.ft
9.0
14.5
5.0
43
66
Torque specifications
Use a torque wrench to tighten these items. It is
recommended that these items be checked occasionally,
specially before a long trip. Always check the tightness of
these items whenever they are loosened for any reason.
!
Torque
Nm
kgf.m Item
Spark plug
Engine oil drain plug
Oil check bolt
Front wheel axle nut
Rear wheel axle nut
12,5
20
7
59
911,25
2,0
0,7
5,9
9,1
A
(Nut)
10 mm
12 mm
14 mm
17 mm
19 mm
22 mmB
(Bolt)
6 mm
8 mm
10 mm
12 mm
14 mm
16 mmGeneral torque especifications
Nm
6
15
30
55
85
130kgf.m
0,6
1,5
3,0
5,5
8,5
13,0lbf. ft
4,3
11
22
40
61
94
lbf.ft
9.0
14.5
5.0
43
66

!!
1. Engine oil filler cap
1. Maximum mark 2.Minimum mark
1
Engine oil
1. Oil level measurement
a. Place the motorcycle on a level place and hold it in anupright position. Warm up the engine for several
minutes.
NOTE:
Be sure the motorcycle is positioned straight up when
checking the oil level. A slight tilt toward the side can result
in false readings.
b. With the engine stopped, with the engine stopped, unscrew the oil filler cap/ dispstick and rest it on the
threads of the ok.
NOTE:
Wait a few minutes until the oil level settles before checking.
c. Remove the oil filler cap/ dispstick, clean it with a dry cloth and check the oil level.
NOTE:
To check the oil level the oil filler cap/ dispstick can not be
screwed, just lightly seated in place. d. The oil level should be between the maximum and
minimum marks. If the level is low, add oil to raise it to the
indicated level, check for oil leakage.
!!
1. Engine oil filler cap
1. Maximum mark 2.Minimum mark
1
Engine oil
1. Oil level measurement
a. Place the motorcycle on a level place and hold it in an
upright position. Warm up the engine for several
minutes.
NOTE:
Be sure the motorcycle is positioned straight up when
checking the oil level. A slight tilt toward the side can result
in false readings.
b. With the engine stopped, with the engine stopped, unscrew the oil filler cap/ dispstick and rest it on the
threads of the ok.
NOTE:
Wait a few minutes until the oil level settles before checking.
c. Remove the oil filler cap/ dispstick, clean it with a dry cloth and check the oil level.
NOTE:
To check the oil level the oil filler cap/ dispstick can not be
screwed, just lightly seated in place. d. The oil level should be between the maximum and
minimum marks. If the level is low, add oil to raise it to the
indicated level, check for oil leakage.

6-7
2. Engine oil and filter replacement
a. Warm up the engine for a few minutes.
b. Stop the engine. Place an oil pan under the engine andremove the dipstick.
c. Remove the drain plug and drain the oil.
d. Reinstall the drain plug, check if the gasket is damaged and lighten it to the specified torque.
Tightening torque:
Drain plug: 20 N.m (2.0 kgf.m, 14.5 lbf.t)
1.Dipstick
1. Engine oil drain plug
1
6-7
2. Engine oil and filter replacement
a. Warm up the engine for a few minutes.
b. Stop the engine. Place an oil pan under the engine andremove the dipstick.
c. Remove the drain plug and drain the oil.
d. Reinstall the drain plug, check if the gasket is damaged and lighten it to the specified torque.
Tightening torque:
Drain plug: 20 N.m (2.0 kgf.m, 14.5 lbf.t)
1.Dipstick
1. Engine oil drain plug
1

6-8
e. Fill engine with oil. Install the oil filter cap and tighten.
NOTE:
Recommended engine oil classification; API Service “SH”
type or equivalent
Do not put in any chemical additives. Engine oil also
lubricates the clutch and additives could cause clutch
slippage.
Be sure no foreign material enters the crankcase. f. Start the engine and warm up for a few minutes.While warming up, check for oil leakage. If oil
leakage is found, stop the engine immediately, and
check for the cause.
g. Stop the engine and check the oil level.
After replacing the engine oil, be sure to check the oil
pressure.
Oil quantity: Total amount:
1.2 L ( 0.264 Imp gal, 0.317 US gal)
Periodic oil change:
1.0 L ( 0.220 Imp gal, 0.264 US gal)
Recommended oil:
Yamalube 4
CAUTION:
CAUTION:
CAUTION:
6-8
e. Fill engine with oil. Install the oil filter cap and tighten.
NOTE:
Recommended engine oil classification; API Service “SH”
type or equivalent
Do not put in any chemical additives. Engine oil also
lubricates the clutch and additives could cause clutch
slippage.
Be sure no foreign material enters the crankcase. f. Start the engine and warm up for a few minutes.While warming up, check for oil leakage. If oil
leakage is found, stop the engine immediately, and
check for the cause.
g. Stop the engine and check the oil level.
After replacing the engine oil, be sure to check the oil
pressure.
Oil quantity: Total amount:
1.2 L ( 0.264 Imp gal, 0.317 US gal)
Periodic oil change:
1.0 L ( 0.220 Imp gal, 0.264 US gal)
Recommended oil:
Yamalube 4
CAUTION:
CAUTION:
CAUTION:

!$ Oil pressure1. Remove the check bolt 
 in the cylinder head.
2. Start the engine and keep it idling until oil flows out
of the bleed hole. If no oil comes out after one
minute, turn off the engine immediately so it will
not seize. In such a case go to the nearest Yamaha
dealer or other qualified mechanic for repairs.
3. After checking, tighten the check bolt to the
specified torque.
Check bolt torque:
7 N.m (0.7 Kgf.m, 5.0 lbf.ft)
1. Check bolt
1
!$ Oil pressure1. Remove the check bolt 
 in the cylinder head.
2. Start the engine and keep it idling until oil flows out
of the bleed hole. If no oil comes out after one
minute, turn off the engine immediately so it will
not seize. In such a case go to the nearest Yamaha
dealer or other qualified mechanic for repairs.
3. After checking, tighten the check bolt to the
specified torque.
Check bolt torque:
7 N.m (0.7 Kgf.m, 5.0 lbf.ft)
1. Check bolt
1

NOTE:
Before checking the throttle cable free play, the engine
idling speed should be adjusted.
The throttle cable should have an specified free play in the
turning direction at the grip flange. If the free play is incorrect,
follow the instructions below.
1. Loosen the locknut.
2. Turning the adjuster to:
Direction A : increase free play
Direction B: reduces free play
3. Tighten the locknut.
!
Free play: 3 ~ 7 mm (0.12 ~ 0.28 in)
Throttle cable adjustment
1. Free play
2. Locknut
3. Adjuster
NOTE:
Before checking the throttle cable free play, the engine
idling speed should be adjusted.
The throttle cable should have an specified free play in the
turning direction at the grip flange. If the free play is incorrect,
follow the instructions below.
1. Loosen the locknut.
2. Turning the adjuster to:
Direction A : increase free play
Direction B: reduces free play
3. Tighten the locknut.
!
Free play: 3 ~ 7 mm (0.12 ~ 0.28 in)
Throttle cable adjustment
1. Free play
2. Locknut
3. Adjuster

!
Drive chain slack adjustment
1. Locknut 2. Adjusting bolt
1. Loosen the rear brake pedal free play adjusting nut.
2. Loosen the axle nut.
3. Loosen the chain adjusting locknuts on each chainpuller. To tighten the chain, turn the chain adjusting nuts
in direction  .To loosen the chain turn the chain
adjusting nuts in direction  and push the wheel
forward. Turn each chain adjusting nut exactly the same
amount to maintain correct axle alignment. There are
marks on each chain puller. Use these marks to align
the rear wheel. Too little chain slack will overload the engine and other vital
parts. Keep the slack within the specified limits.
To maintain correct axle alignment, Ensure the notch on
the adjuster is on the same mark on left and right side
4. After adjusting, be sure to tighten each chain adjusting
locknut. The tighten the axle nut to the specified torque
Axle nut torque: 91 N.m (9.1 Kgf.m, 66 lbf.ft)
Locknut torque: 15 N.m (1.5 Kgf.m, 11 lbf.ft)
5. Adjust the free play in the brake pedal.
Check the operation of the brake light after adjusting
the rear brake.
CAUTION:
CAUTION:
!
Drive chain slack adjustment
1. Locknut 2. Adjusting bolt
1. Loosen the rear brake pedal free play adjusting nut.
2. Loosen the axle nut.
3. Loosen the chain adjusting locknuts on each chain puller. To tighten the chain, turn the chain adjusting nuts
in direction  .To loosen the chain turn the chain
adjusting nuts in direction  and push the wheel
forward. Turn each chain adjusting nut exactly the same
amount to maintain correct axle alignment. There are
marks on each chain puller. Use these marks to align
the rear wheel. Too little chain slack will overload the engine and other vital
parts. Keep the slack within the specified limits.
To maintain correct axle alignment, Ensure the notch on
the adjuster is on the same mark on left and right side
4. After adjusting, be sure to tighten each chain adjusting
locknut. The tighten the axle nut to the specified torque
Axle nut torque: 91 N.m (9.1 Kgf.m, 66 lbf.ft)
Locknut torque: 15 N.m (1.5 Kgf.m, 11 lbf.ft)
5. Adjust the free play in the brake pedal.
Check the operation of the brake light after adjusting
the rear brake.
CAUTION:
CAUTION:

6-24
Throttle cable and grip lubrication
The throttle twist grip assembly should be greased at the
time the cable is lubricated, since the grip must be removed
to get at the end of the throttle cable.
After removing the screws, hold the end of the cable up in
the air and put in several drops of lubricant. With the throttle
grip disassembled, coat the metal surface of the grip
assembly with a suitable all-purpose grease.Brake and shift pedals
Lubricate the pivoting parts.
RECOMMENDED LUBRICANT: Engine oil SAE 20W50
Brake and clutch levers
Lubricate the pivoting parts. RECOMMENDED LUBRICANT: Engine oil SAE 20W50
Sidestand
Lubricate the pivoting parts. Check to see that the sidestand
moves up and down smoothly. RECOMMENDED LUBRICANT: Engine oil SAE 20W50
WARNING:
If the sidestand does not move smoothly, consult a
Yamaha dealer.
CAUTION:
6-24
Throttle cable and grip lubrication
The throttle twist grip assembly should be greased at the
time the cable is lubricated, since the grip must be removed
to get at the end of the throttle cable.
After removing the screws, hold the end of the cable up in
the air and put in several drops of lubricant. With the throttle
grip disassembled, coat the metal surface of the grip
assembly with a suitable all-purpose grease. Brake and shift pedals
Lubricate the pivoting parts.
RECOMMENDED LUBRICANT: Engine oil SAE 20W50
Brake and clutch levers
Lubricate the pivoting parts. RECOMMENDED LUBRICANT: Engine oil SAE 20W50
Sidestand
Lubricate the pivoting parts. Check to see that the sidestand
moves up and down smoothly. RECOMMENDED LUBRICANT: Engine oil SAE 20W50
WARNING:
If the sidestand does not move smoothly, consult a
Yamaha dealer.
CAUTION:

6-37Never check the fuel system while smoking or in the
vicinity of an open flame.
Check if there is
fuel in the fuel tank
Use electric
starter
Remove spark
plug and check
electrode
Use electric starter 1. Fuel
2. Compression
3. Ignition
4. BatteryEnough fuel
No fuel
There is compression
No compression
Wet
Dry
Engine turns
over quickly
Engine turns
over slowlySupply fuel
Go to ignition check
Ask Yamaha dealer to inspect
Wipe clean with dry cloth and correct
spark plug gap or replace spark plugs
Ask Yamaha dealer to inspect
Battery good
Check fluid,
recharge and check
connections
Troubleshooting chart
Go to compression
check
Engine doesn’t start, go
to compression check
Open the throttle hal-way
and start the engine
Engine doesn’t start, ask
Yamaha dealer to inspect.Engine doesn’t start,
go to battery check
WARNING:
6-37Never check the fuel system while smoking or in the
vicinity of an open flame.
Check if there is
fuel in the fuel tank
Use electric
starter
Remove spark
plug and check
electrode
Use electric starter 1. Fuel
2. Compression
3. Ignition
4. BatteryEnough fuel
No fuel
There is compression
No compression
Wet
Dry
Engine turns
over quickly
Engine turns
over slowlySupply fuel
Go to ignition check
Ask Yamaha dealer to inspect
Wipe clean with dry cloth and correct
spark plug gap or replace spark plugs
Ask Yamaha dealer to inspect
Battery good
Check fluid,
recharge and check
connections
Troubleshooting chart
Go to compression
check
Engine doesn’t start, go
to compression check
Open the throttle hal-way
and start the engine
Engine doesn’t start, ask
Yamaha dealer to inspect.Engine doesn’t start,
go to battery check
WARNING: