2016 YAMAHA YZ250F Owners Manual

BASIC SERVICE INFORMATION
1-11
ECA16790
NOTICE
When disconnecting a connector, do not
pull the leads. Hold both sections of the
connector, and then disconnect the con-
nector.
2. Check:
• Lead
• Coupler
• Connector
Moisture  Dry with compressed air.
Rust/stains  Connect and disconnect sev-
eral times.
3. Check:
• All connections
Loose connection  Connect properly.
TIP
• If the pin “1” on the terminal is flattened, bend
it up.
• After disassembling or assembling a coupler,
pull on the leads to make sure that they are in-
stalled securely.4. Connect:
• Lead
• Coupler
• Connector
TIP
• When connecting a coupler or a connector,
make sure that both terminals are connected
securely.
• Make sure all connections are tight.
1

BASIC SERVICE INFORMATION
1-12
5. Check:
• No continuity
TIP
• If there is no continuity, clean the terminals.
• When checking the wire harness, perform
steps (1) to (4).
• As a quick remedy, use a contact revitalizer
available at most part stores.Pocket tester
90890-03112
Analog pocket tester
YU-03112-C

SPECIAL TOOLS
1-13
EAS1SM9028
SPECIAL TOOLS
The following special tools are required for accurate and complete adjustment and assembly. Using
the correct special tool will help prevent damage caused by the use of improper tools or improvised
techniques. The shape and tool number used for the special tool differ by country, so two types are
provided. Refer to the list provided to avoid errors when placing an order.
TIP
• For U.S.A. and Canada, use tool number starting with “YM-”, “YU-”, or “ACC-”.
• For others, use tool number starting with “90890-”.
Tool name/Part number How to use Illustration
Dial gauge & stand set
90890-01252
Dial gauge set
YU-03097-BThis tool is used to check
parts for runout or bend.
Crankshaft installer pot
90890-01274
Installing pot
YU-90058This tool is used to install the
crankshaft.
Crankshaft installer bolt
90890-01275
Bolts
YU-90060This tool is used to install the
crankshaft.
Adapter (M12)
90890-01278
Adapter #3
YU-90063This tool is used to install the
crankshaft.
Piston pin puller set
90890-01304
Piston pin puller
YU-01304This tool is used to remove
the piston pin.

SPECIAL TOOLS
1-14
Radiator cap tester
90890-01325
Mityvac cooling system tester
kit
YU-24460-AThis tool is used to check the
radiator and the radiator cap.
Radiator cap tester adapter
90890-01352
Pressure tester adapter
YU-33984This tool is used to check the
radiator and the radiator cap.
Steering nut wrench
90890-01403
Exhaust flange nut wrench
YU-A9472This tool is used to remove or
tighten the steering nut.
Cap bolt wrench
90890-01500
YM-01500This tool is used to remove or
tighten the base valve.
Cap bolt ring wrench
90890-01501
YM-01501This tool is used to loosen or
tighten the damper assem-
bly.
Fork seal driver
90890-01502
YM-A0948This tool is used to install the
oil seal of the front fork.
Spoke nipple wrench (6–7)
90890-01521
YM-01521This tool is used to tighten the
spoke. Tool name/Part number How to use Illustration

SPECIAL TOOLS
1-15
Pocket tester
90890-03112
Analog pocket tester
YU-03112-CThis tool is used to measure
the voltage, current, and re-
sistance of electrical compo-
nents.
Timing light
90890-03141
YU-03141This tool is used to measure
the ignition timing.
Pressure gauge
90890-03153
YU-03153This tool is used to measure
the fuel pressure.
Fuel pressure adapter
90890-03186
YM-03186This tool is used to mount the
pressure gauge.
Test harness S-pressure
sensor (3P)
90890-03207
YU-03207This tool is used to check the
throttle position sensor input
voltage.
FI diagnostic tool sub-lead
90890-03212
YU-03212This tool is used to connect
the Yamaha diagnostic tool
to a battery.
Yamaha diagnostic tool
90890-03231
Yamaha diagnostic tool (US)
90890-03234This tool is used to check er-
ror codes or carry out self-di-
agnosis.
Valve spring compressor
90890-04019
YM-04019This tool is used to discon-
nect or connect the valve and
the valve spring. Tool name/Part number How to use Illustration
YM-04019

SPECIAL TOOLS
1-16
Spacer (crankshaft installer)
90890-04081
Pot spacer
YM-91044This tool is used to install the
crankshaft.
Clutch holder
90890-04086
YM-91042This tool is used to hold the
clutch when removing or in-
stalling the clutch boss secur-
ing nut.
Valve guide remover (ø5)
90890-04097
Valve guide remover (5.0
mm)
YM-04097This tool is used to replace
the valve guide.
Valve guide installer (ø5)
90890-04098
Valve guide installer (5.0
mm)
YM-04098This tool is used to replace
the valve guide.
Valve guide reamer (ø5)
90890-04099
Valve guide reamer (5.0 mm)
YM-04099This tool is used to replace
the valve guide.
Valve lapper
90890-04101
Valve lapping tool
YM-A8998This tool is used to remove
the valve lifter or lap the
valve.
Valve spring compressor
adapter 22 mm
90890-04108
YM-04108This tool is used to discon-
nect or connect the valve and
the valve spring. Tool name/Part number How to use Illustration
YM-91044

SPECIAL TOOLS
1-17
Valve guide remover (ø4.5)
90890-04116
Valve guide remover (4.5
mm)
YM-04116This tool is used to replace
the valve guide.
Valve guide installer (ø4.5)
90890-04117
Valve guide installer (4.5
mm)
YM-04117This tool is used to replace
the valve guide.
Valve guide reamer (ø4.5)
90890-04118
Valve guide reamer (4.5 mm)
YM-04118This tool is used to replace
the valve guide.
Rotor puller
90890-04151
YM-04151This tool is used to remove
the rotor.
Crankcase separating tool
90890-04152
YU-A9642This tool is used to remove
the crankshaft.
Ignition checker
90890-06754
Oppama pet-4000 spark
checker
YM-34487This tool is used to check the
spark performance of the ig-
nition coil.
Digital tachometer
90890-06760
YU-39951-BThis tool is used to measure
the engine speed.
Three bond No.1215®
90890-85505This sealant (Bond) is used
for crankcase mating sur-
face, etc. Tool name/Part number How to use Illustration

CONTROL FUNCTIONS
1-18
EAS1SM9029
CONTROL FUNCTIONS
EAS1SM9030ENGINE STOP SWITCH
The engine stop switch “1” is located on the left
handlebar. Continue pushing the engine stop
switch till the engine comes to a stop.
EAS1SM9031CLUTCH LEVER
The clutch lever “1” is located on the left han-
dlebar. The clutch lever disengages or engag-
es the clutch.
Pull the clutch lever toward the handlebar to
disengage the clutch, and release the lever to
engage the clutch.
EAS1SM9032SHIFT PEDAL
The shift pedal “1” has adopted a method of 1
down & 4 ups (press-down & kick-ups).
Press it down for N (neutral) to 1st, and kick it
up for 2nd to 5th.
EAS1SM9033KICKSTARTER LEVER
The kickstarter lever “1” is in the right of the
chassis.
To start the engine, pull out and push down the
kickstarter lever with your foot.
EAS1SM9034THROTTLE GRIP
The throttle grip “1” is located on the right han-
dlebar. The throttle grip accelerates or deceler-
ates the engine. For acceleration, turn the grip
toward you; for deceleration, turn it away from
you.
EAS1SM9035FRONT BRAKE LEVER
The front brake lever “1” is located on the right
handlebar. Pull it toward the handlebar to acti-
vate the front brake.
1
1