2014 YAMAHA WR 250F height

5-10
CARBURETOR
16. Install:
• Jet needle "1"
•Collar "2"
• Spring "3"
• Needle holder "4"
• Throttle valve plate "5"
To throttle valve "6".
17. Install:
• Throttle valve assembly "1"
• Screw (throttle shaft) "2"
Install the valve lever rollers "3" into
the slits "a" of the throttle valve.
18. Install:
• O-ring "1"
• Valve lever housing cover "2"
• Bolt (valve lever housing cover)
"3"
19. Install:
• Carburetor breather hose "1"
Install the carburetor breather hoses
to the carburetor so that the hoses do
not bend near where they are in-
stalled.
ADJUSTING THE ACCELERATOR
PUMP TIMING
Adjustment steps:
In order for the throttle valve height
"a" to achieve the specified value,
tuck under the throttle valve plate "1"
the rod "2" etc. with the same outer di-
ameter as the specified value.
a. Fully turn in the accelerator pump
adjusting screw "3".
b. Check that the link lever "4" has
free play "b" by pushing lightly on
it.
c. Gradually turn out the adjusting
screw while moving the link lever
until it has no more free play.
INSTALLING THE CARBURETOR
1. Install:
• Carburetor joint "1"
2. Install:
• Carburetor "1"
Install the projection "a" between the
carburetor joint slots.
3. Install:
• Hot starter plunger "1"
4. Tighten:
• Bolt (carburetor joint) "1"
• Bolt (air filter joint) "2"
5. Install:
• Throttle cable (pull) "1"
• Throttle cable (return) "2"
Throttle valve height:
0.8 mm (0.031 in)
Carburetor joint:
10 Nm (1.0 m•kg, 7.2
ft•lb)
Hot starter plunger:
2 Nm (0.2 m•kg, 1.4
ft•lb)
Bolt (carburetor joint):
3 Nm (0.3 m•kg, 2.2
ft•lb)
Bolt (air filter joint):
3 Nm (0.3 m•kg, 2.2
ft•lb)
Throttle cable (pull):
4 Nm (0.4 m•kg, 2.9
ft•lb)
Throttle cable (return):
11 Nm (1.1 m•kg, 8.0
ft•lb)

5-22
VALVES AND VALVE SPRINGS
REMOVING THE VALVE LIFTER
AND VALVE COTTER
1. Remove:
• Valve lifter "1"
• Pad "2"
Identify each lifter "1" and pad "2" po-
sition very carefully so that they can
be reinstalled in their original place.
2. Check:
• Valve sealing
Leakage at the valve seat→In-
spect the valve face, valve seat
and valve seat width.
Checking steps:
a. Pour a clean solvent "1" into the
intake and exhaust ports.
b. Check that the valve seals prop-
erly.
There should be no leakage at the
valve seat "2".
3. Remove:
• Valve cotter
Remove the valve cotters by com-
pressing the valve spring with the
valve spring compressor "1" and the
valve spring compressor attachment
"2".
CHECKING THE VALVE
1. Measure:
• Stem-to-guide clearance
Out of specification→Replace the
valve guide.
2. Replace:
• Valve guide
Replacement steps:
To ease guide removal, installation
and to maintain correct fit heat the
cylinder head in an over to 100 °C
(212 °F).
a. Remove the valve guide using a
valve guide remover "1".
b. Install the new valve guide using a
valve guide remover "1" and valve
guide installer "2".
c. After installing the valve guide,
bore the valve guide using a valve
guide reamer "3" to obtain proper
stem-to-guide clearance.
After replacing the valve guide reface
the valve seat.
Valve spring compres-
sor:
YM-04019/90890-04019
Valve spring compressor
adapter 19.5 mm:
YM-04114
Valve spring compressor
attachment:
90890-04114
Stem-to-guide clearance = valve
guide inside diameter "a" -
valve stem diameter "b"
Clearance (stem to
guide):
Intake:
0.010–0.037 mm
(0.0004–0.0015 in)
:0.08 mm
(0.003 in)
Exhaust:
0.025–0.052 mm
(0.0010–0.0020 in)
:0.10 mm
(0.004 in)
Valve guide installation
height "a":
Intake:
11.8–12.2 mm (0.46–
0.48 in)
Exhaust:
11.3–11.7 mm (0.44–
0.46 in)
Valve guide remover:
Intake:4.0 mm (0.16 in)
YM-04111/90890-04111
Exhaust:4.5 mm (0.18
in)
YM-04116/90890-04116
Valve guide installer:
Intake:4.0 mm (0.16 in)
YM-04112/90890-04112
Exhaust:4.5 mm (0.18
in)
YM-04117/90890-04117
Valve guide reamer:
Intake:4.0 mm (0.16 in)
YM-04113/90890-04113
Exhaust:4.5 mm (0.18
in)
YM-04118/90890-04118

6-13
FRONT BRAKE AND REAR BRAKE
A. Front
B. Rear
INSTALLING THE FRONT BRAKE
MASTER CYLINDER
1. Install:
• Brake master cylinder "1"
• Brake master cylinder bracket "2"
• Bolt (brake master cylinder brack-
et) "3"
• Install the bracket so that the arrow
mark "a" face upward.
• First tighten the bolts on the upper
side of the brake master cylinder
bracket, and then tighten the bolts
on the lower side.
2. Install:
• Brake lever "1"
• Bolt (brake lever) "2"• Nut (brake lever) "3"
Apply the silicone grease on the
brake lever sliding surface, bolt and
contacting surface of the brake mas-
ter cylinder piston.
INSTALLING THE REAR BRAKE
MASTER CYLINDER
1. Install:
• Copper washer "1"
• Brake hose "2"
• Union bolt "3"
Always use new copper washers.
Install the brake hose so that its
pipe portion "a" directs as shown
and lightly touches the projection
"b" on the brake master cylinder.
2. Install:
• Brake master cylinder "1"
• Bolt (brake master cylinder) "2"
3. Install:
• Spring "1"
• Brake pedal "2"
• O-ring "3"
• Bolt (brake pedal) "4"
• Clip "5"
Apply the lithium soap base grease
on the bolt, O-ring and brake pedal
bracket.
4. Install:
•Pin "1"
• Washer "2"
• Cotter pin "3"
After installing, check the brake pedal
height. Refer to "ADJUSTING THE
REAR BRAKE" section in the CHAP-
TER 3.
Bolt (brake master cylin-
der bracket):
9 Nm (0.9 m•kg, 6.5
ft•lb)
Bolt (brake lever):
6 Nm (0.6 m•kg, 4.3
ft•lb)
Nut (brake lever):
6 Nm (0.6 m•kg, 4.3
ft•lb)
Union bolt:
30 Nm (3.0 m•kg, 22
ft•lb)
Bolt (brake master cylin-
der):
10 Nm (1.0 m•kg, 7.2
ft•lb)
Bolt (brake pedal):
26 Nm (2.6 m•kg, 19
ft•lb)