2010 YAMAHA YZF-R125 radiator

INSTRUMENT AND CONTROL FUNCTIONS
3-3
3
TIP

For radiator-fan-equipped vehi-
cles, the radiator fan(s) automati-
cally switch on or off according to
the coolant temperature in the ra-
diator.


If the engine overheats, see page
6-38 for further instructions.
EAUT1934
Engine trouble warning light“”
This warning light flashes or stays on if
an electrical circuit monitoring the en-
gine is not working correctly. If this oc-
curs, have a Yamaha dealer check the
self-diagnosis system.
The electrical circuit of the warning light
can be checked by turning the key to
“ON”. The warning light should come
on for a few seconds, and then go off.
If the warning light does not come on
initially when the key is turned to “ON”,
or if the warning light remains on, have
a Yamaha dealer check the electrical
circuit.
EAU11872
Tachometer The electric tachometer allows the rider
to monitor the engine speed and keep it
within the ideal power range.
When the key is turned to “ON”, the ta-
chometer needle will sweep once
across the r/min range and then return
to zero r/min in order to test the electri-
cal circuit.NOTICE
ECA10031
Do not operate the engine in the ta-
chometer red zone.
Red zone: 10000 r/min and above
EAUM2303
Multi-function display
WARNING
EWA12312
Be sure to stop the vehicle before
making any setting changes to the
multi-function display. Changing
settings while riding can distract the
operator and increase the risk of an
accident.The multi-function display is equipped
with the following:

a speedometer (which shows the
riding speed)


an odometer (which shows the to-
tal distance traveled)
1. Tachometer
2. Tachometer red zone
1. Multi-function display
2.“RESET/SELECT” button
U5D7E1E0.book Page 3 Monday, July 13, 2009 11:55 AM

PERIODIC MAINTENANCE AND ADJUSTMENT
6-14
6 3. If the coolant is at or below the
minimum level mark, remove the
reservoir cap.4. Add coolant to the maximum level
mark, and then install the reservoir
cap. WARNING! Remove only
the coolant reservoir cap. Never
attempt to remove the radiator
cap when the engine is hot.
[EWA15161]
NOTICE: If coolant is not
available, use distilled water or
soft tap water instead. Do not
use hard water or salt water
since it is harmful to the engine.
If water has been used instead
of coolant, replace it with cool-
ant as soon as possible, other-
wise the cooling system will not
be protected against frost and
corrosion. If water has been
added to the coolant, have a
Yamaha dealer check the anti-
freeze content of the coolant as
soon as possible, otherwise the
effectiveness of the coolant will
be reduced.
[ECA10472]EAU33031
Changing the coolant
The coolant must be changed at the in-
tervals specified in the periodic mainte-
nance and lubrication chart. Have a
Yamaha dealer change the coolant.
WARNING! Never attempt to remove
the radiator cap when the engine is
hot.
[EWA10381]
1. Coolant reservoir
2. Maximum level mark
3. Minimum level mark
1. Coolant reservoir cap
Coolant reservoir capacity (up to
the maximum level mark):
0.25 L (0.26 US qt, 0.22 Imp.qt)
U5D7E1E0.book Page 14 Monday, July 13, 2009 11:55 AM

PERIODIC MAINTENANCE AND ADJUSTMENT
6-31
6pelled from the battery, the
frame could suffer structural
and external damages.
[ECA10601]EAUM2412
Replacing the fuses The fuse box is located under the rider
seat. (See page 3-10.)
If a fuse is blown, replace it as follows.
1. Turn the key to “OFF” and turn off
the electrical circuit in question.
2. Remove the blown fuse, and then
install a new fuse of the specified
amperage. WARNING! Do not
use a fuse of a higher amperage
rating than recommended toavoid causing extensive dam-
age to the electrical system and
possibly a fire.
[EWA15131]
3. Turn the key to “ON” and turn on
the electrical circuit in question to
check if the device operates.
4. If the fuse immediately blows
again, have a Yamaha dealer
check the electrical system.
1. Fuse box
2. Spare fuse
3. Headlight fuse
4. Signaling system fuse
5. Ignition fuse
6. Radiator fan fuse
7. Main fuse
Specified fuses:
Main fuse:
20.0 A
Ignition fuse:
7.5 A
Signaling system fuse:
7.5 A
Headlight fuse:
15.0 A
Radiator fan fuse:
5.0 A
U5D7E1E0.book Page 31 Monday, July 13, 2009 11:55 AM

PERIODIC MAINTENANCE AND ADJUSTMENT
6-39
6Engine overheating
WARNING
EWA10400


Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be
blown out under pressure, which could cause serious injury. Be sure to wait until the engine has cooled.


After removing the radiator cap retaining bolt, place a thick rag, like a towel, over the radiator cap, and then
slowly rotate the cap counterclockwise to the detent to allow any residual pressure to escape. When the hissing
sound has stopped, press down on the cap while turning it counterclockwise, and then remove the cap.
TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended coolant
as soon as possible.
Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again,
have a
Yamaha dealer check
and repair the cooling system.
There is
leakage.
There is
no leakage.
U5D7E1E0.book Page 39 Monday, July 13, 2009 11:55 AM

SPECIFICATIONS
8-1
8
Dimensions:Overall length:
2015 mm (79.3 in)
Overall width:
660 mm (26.0 in)
Overall height:
1065 mm (41.9 in)
Seat height:
818 mm (32.2 in)
Wheelbase:
1355 mm (53.3 in)
Ground clearance:
155 mm (6.10 in)
Minimum turning radius:
3100 mm (122.0 in)Weight:With oil and fuel:
138.0 kg (304 lb)Engine:Engine type:
Liquid cooled 4-stroke, SOHC
Cylinder arrangement:
Forward-inclined single cylinder
Displacement:
124 cm³
Bore × stroke:
52.0 × 58.6 mm (2.05 × 2.31 in)
Compression ratio:
11.20 :1
Starting 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
standard MA
Engine oil quantity:
Without oil filter element replacement:
0.95 L (1.00 US qt, 0.84 Imp.qt)
With oil filter element replacement:
1.00 L (1.06 US qt, 0.88 Imp.qt)Cooling system:Coolant reservoir capacity (up to the
maximum level mark):
0.25 L (0.26 US qt, 0.22 Imp.qt)
Radiator capacity (including all routes):
1.00 L (1.06 US qt, 0.88 Imp.qt)Air filter:Air filter element:
Dry element
Fuel:Recommended fuel:
Premium unleaded gasoline only
Fuel tank capacity:
13.8 L (3.65 US gal, 3.04 Imp.gal)
Fuel reserve amount:
1.6 L (0.42 US gal, 0.35 Imp.gal)Fuel injection:Throttle body:
ID mark:
5D71 00Spark plug (s):Manufacturer/model:
NGK/CR8E
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)Clutch:Clutch type:
Wet, multiple-discTransmission:Primary reduction system:
Helical gear
Primary reduction ratio:
73/24 (3.042)
Secondary reduction system:
Chain drive
Secondary reduction ratio:
48/14 (3.429)
Transmission type:
Constant mesh 6-speed
Operation:
Left foot operation
-20 -10 0
10 20 30
40
50 ˚C
SAE 10W-30
SAE 15W-40SAE 20W-40SAE 20W-50
SAE 10W-40SAE 10W-50
U5D7E1E0.book Page 1 Monday, July 13, 2009 11:55 AM

SPECIFICATIONS
8-3
8
Battery:Model:
12N5.5-3B / YUASA
Voltage, capacity:
12 V, 5.5 AhHeadlight:Bulb type:
Halogen bulbBulb voltage, wattage × quantity:Headlight:
12 V, 55 W × 2
Tail/brake light:
LED x 8
Front turn signal light:
12 V, 10.0 W × 2
Rear turn signal light:
12 V, 10.0 W × 2
Auxiliary light:
12 V, 5.0 W × 2
Meter lighting:
LED
Neutral indicator light:
LED
High beam indicator light:
LED
Turn signal indicator light:
LED
Coolant temperature warning light:
LED
Engine trouble warning light:
LEDFuses:Main fuse:
20.0 AHeadlight fuse:
15.0 A
Signaling system fuse:
7.5 A
Ignition fuse:
7.5 A
Radiator fan fuse:
5.0 A
U5D7E1E0.book Page 3 Monday, July 13, 2009 11:55 AM