2010 YAMAHA YZF-R125 transmission

INSTRUMENT AND CONTROL FUNCTIONS
3-2
3To unlock the steering
Push the key into the main switch, and
then turn it to “OFF” while still pushing
it.
EAU11004
Indicator and warning lights
EAU11020
Turn signal indicator light“”
This indicator light flashes when the
t u r n s i g n a l s w i t c h i s p u s h e d t o t h e l e f t o r
right.
EAU11060
Neutral indicator light“”
This indicator light comes on when the
transmission is in the neutral position.
EAU11080
High beam indicator light“”
This indicator light comes on when the
high beam of the headlight is switched
on.
EAUM2294
Coolant temperature warning
light“”
This warning light comes on if the en-
gine overheats. If this occurs, stop the
engine immediately and allow the en-
gine to cool.
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.NOTICE
ECA10021
Do not continue to operate the en-
gine if it is overheating.
1. Push.
2. Turn.
1. Neutral indicator light“”
2. Turn signal indicator light“”
3. High beam indicator light“”
4. Engine trouble warning light“”
5. Coolant temperature warning light“”
U5D7E1E0.book Page 2 Monday, July 13, 2009 11:55 AM

INSTRUMENT AND CONTROL FUNCTIONS
3-6
3
EAU12820
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 igni-
tion circuit cut-off system. (See page
3-11.)
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 6-speed con-
stant-mesh transmission equipped on
this motorcycle.
EAU12890
Brake lever The brake lever is located at the right
handlebar grip. To apply the front
brake, pull the lever toward the handle-
bar grip.
1. Clutch lever
1. Shift pedal
1. Brake lever
U5D7E1E0.book Page 6 Monday, July 13, 2009 11:55 AM

INSTRUMENT AND CONTROL FUNCTIONS
3-11
3 below and have a Yamaha dealer re-
pair it if it does not function proper-
ly.
EAU44892
Ignition circuit cut-off system The ignition circuit cut-off system (com-
prising the sidestand switch, clutch
switch and neutral switch) has the fol-
lowing functions.

It prevents starting when the trans-
mission is in gear and the side-
stand is up, but the clutch lever is
not pulled.


It prevents starting when the trans-
mission is in gear and the clutch le-
ver is pulled, but the sidestand is
still down.


It cuts the running engine when the
transmission is in gear and the sid-
estand is moved down.
Periodically check the operation of the
ignition circuit cut-off system according
to the following procedure.
U5D7E1E0.book Page 11 Monday, July 13, 2009 11:55 AM

INSTRUMENT AND CONTROL FUNCTIONS
3-12
3
With the engine turned off:
1. Move the sidestand down.
2. Make sure that the engine stop switch is set to “
3. Turn the key on.
4. Shift the transmission into the neutral position.
5. Push the start switch.
Does the engine start?
With the engine still running:
6. Move the sidestand up.
7. Keep the clutch lever pulled.
8. Shift the transmission into gear.
9. Move the sidestand down.
Does the engine stall?
After the engine has stalled:
10. Move the sidestand up.
11. Keep the clutch lever pulled.
12. Push the start switch.
Does the engine start?
The system is OK. The motorcycle can be ridden.The neutral switch may not be working correctly.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
The sidestand switch may not be working correctly.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
The clutch switch may not be working correctly.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
YES NO YES NO YES NO
If a malfunction is noted, have a Yamaha
dealer check the system before riding.
WARNING
”.
U5D7E1E0.book Page 12 Monday, July 13, 2009 11:55 AM

OPERATION AND IMPORTANT RIDING POINTS
5-1
5
EAU15951
Read the Owner’s Manual carefully to
become familiar with all controls. If
there is a control or function you do not
understand, ask your Yamaha dealer.
WARNING
EWA10271
Failure to familiarize yourself with
the controls can lead to loss of con-
trol, which could cause an accident
or injury.
EAU45310
TIPThis model is equipped with a lean an-
gle sensor to stop the engine in case of
a turnover. To start the engine after a
turnover, be sure to turn the main
switch to “OFF” and then to “ON”. Fail-
ing to do so will prevent the engine from
starting even though the engine will
crank when pushing the start switch.
EAUM2322
Starting the engine In order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:

The transmission is in the neutral
position.


The transmission is in gear with
the clutch lever pulled and the sid-
estand up.
See page 3-11 for more informa-
tion.
1. Turn the key to “ON” and make
sure that the engine stop switch is
set to“”.
The following warning lights and
indicator light should come on for a
few seconds, then go off.

Neutral indicator light


Turn signal indicator light


High beam indicator light


Coolant temperature warning
light


Engine trouble warning light
U5D7E1E0.book Page 1 Monday, July 13, 2009 11:55 AM

OPERATION AND IMPORTANT RIDING POINTS
5-2
5
NOTICE
ECA11831
If a warning or indicator light does
not go off, see page 3-2 for the corre-
sponding warning and indicator
light circuit check.2. Shift the transmission into the neu-
tral position. (See page 5-2.) The
neutral indicator light should come
on. If not, ask a Yamaha dealer to
check the electrical circuit.
3. Start the engine by pushing the
start switch. NOTICE: For maxi-
mum engine life, never acceler-
ate hard when the engine is
cold!
[ECA11041]
If the engine fails to start, release
the start switch, wait a few sec-
onds, and then try again. Each
starting attempt should be as short
as possible to preserve the bat-
tery. Do not crank the engine more
than 10 seconds on any one at-
tempt.
EAU16671
Shifting Shifting gears lets you control the
amount of engine power available for
starting off, accelerating, climbing hills,
etc.
The gear positions are shown in the il-
lustration.TIPTo shift the transmission into the neu-
tral position, press the shift pedal down
repeatedly until it reaches the end of its
travel, and then slightly raise it.
NOTICE
ECA10260


Even with the transmission in
the neutral position, do not
coast for long periods of time
with the engine off, and do not
tow the motorcycle for long dis-
tances. The transmission is
properly lubricated only when
the engine is running. Inade-
quate lubrication may damage
the transmission.


Always use the clutch while
changing gears to avoid damag-
ing the engine, transmission,
and drive train, which are not
designed to withstand the
shock of forced shifting.
1. Shift pedal
2. Neutral position
U5D7E1E0.book Page 2 Monday, July 13, 2009 11:55 AM

PERIODIC MAINTENANCE AND ADJUSTMENT
6-23
6


Be careful that water does not en-
ter the brake fluid reservoir when
refilling. Water will significantly
lower the boiling point of the fluid
and may result in vapor lock.


Brake fluid may deteriorate paint-
ed surfaces or plastic parts. Al-
ways clean up spilled fluid
immediately.


As the brake pads wear, it is nor-
mal for the brake fluid level to grad-
ually go down. However, if the
brake fluid level goes down sud-
denly, have a Yamaha dealer
check the cause.
EAUM1360
Changing the brake fluid Have a Yamaha dealer change the
brake fluid at the intervals specified in
the periodic maintenance and lubrica-
tion chart. In addition, have the brake
hose replaced every four years or
whenever it is damaged or leaking.
EAU22760
Drive chain slack The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU22773
To check the drive chain slack
1. Place the motorcycle on the side-
stand.TIPWhen checking and adjusting the drive
chain slack, there should be no weight
on the motorcycle.2. Shift the transmission into the neu-
tral position.
3. Move the rear wheel by pushing
the motorcycle to locate the tight-
est portion of the drive chain, and
then measure the drive chain slack
as shown.Drive chain slack:
30.0–40.0 mm (1.18–1.57 in)
U5D7E1E0.book Page 23 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