2011 YAMAHA WR 450F seats

3-3
MAINTENANCE INTERVALS FOR COMPETITION USE
• The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
• Hydraulic brake service
• After disassembling the brake master cylinders and calipers, always change the fluid. Regularly check the brake fluid
levels and fill the reservoirs as required.
• Every two years replace the internal components of the brake master cylinders and calipers, and change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.
MAINTENANCE INTERVALS FOR COMPETITION USE
• The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind that such factors as
weather, terrain, geographical location, and individual usage will alter the required maintenance and lubrication intervals.
If you are a doubt as to what intervals to follow in maintaining and lubricating your machine, consult your Yamaha dealer.
• Periodic inspection is essential in making full use of the machine performance. The service life of the parts varies sub-
stantially according to the environment in which the machine runs (e.g., rain, dirt, etc.). Therefore, earlier inspection is
required by reference to the list below.
15 Sidestand pivotCheck operation.
√√√
Apply lithium-soap-based grease (all-purpose
grease) lightly.
16 * Front forkCheck operation and for oil leakage.
√√
Replace if necessary.
17 * Shock absorber assemblyCheck operation and for oil leakage.
√√
Replace if necessary.
18 * Rear suspension link pivots Apply molybdenum disulfide grease lightly.√√
19 * Control cablesApply Yamaha chain and cable lube or engine
oil 10W-30 thoroughly.√√√
20 * Throttle grip housing and cableCheck operation and free play.
√√√ Adjust the throttle cable free play if necessary.
Lubricate the throttle grip housing and cable.
21 * Chassis fastenersCheck all chassis fitting and fasteners.
√√√
Correct if necessary.
22 Battery Check terminal for looseness and corrosion.√√ No. ITEM CHECKS AND MAINTENANCE JOBSINITIALODOMETER
READINGS
600 mi
(1,000
km) or 1
month1,800 mi
(3,000
km) or 3
months3,000 mi
(5,000
km) or 6
months
ItemAfter
break-
inEvery
race
Every
third
(or 500
km)Every
fifth (or
1,000
km)
As re-
quiredRemarks
ENGINE OIL
Replace●●
VALVES
Check the valve clearances●●The engine must be cold.
Inspect●Check the valve seats and valve
stems for wear.
Replace●
VALVE SPRINGS
Inspect●Check the free length and the tilt.
Replace●

5-21
CYLINDER HEAD
CHECKING THE CYLINDER HEAD
1. Eliminate:
• Carbon deposits (from the com-
bustion chambers)
Use a rounded scraper.
Do not use a sharp instrument to
avoid damaging or scratching:
• Spark plug threads
• Valve seats
2. Inspect:
• Cylinder head
Scratches/damage→Replace.
Replace the titanium valves with the
cylinder head.
Refer to "CHECKING THE
VALVE".
3. Measure:
• Cylinder head warpage
Out of specification→Resurface.
Warpage measurement and resur-
facing steps:
a. Place a straightedge and a feeler
gauge across the cylinder head.
b. Use a feeler gauge to measure
the warpage.
c. If the warpage is out of specifica-
tion, resurface the cylinder head.
d. Place a 400–600 grit wet sandpa-
per on the surface plate, and re-
surface the head using a figure-
eight sanding pattern.
To ensure an even surface rotate the
cylinder head several times.
INSTALLING THE CYLINDER
HEAD
1. Install:
• Timing chain guide (exhaust side)
"1"
• Dowel pin "2"
• Cylinder head gasket "3"
• Cylinder head "4"
While pulling up the timing chain, in-
stall the timing chain guide (exhaust
side) and cylinder head.
2. Install:
• Washer "1"
• Bolts "2"
Installation steps:
Tighten the cylinder head using
the rotation angle procedure to ob-
tain uniform tightening torque.
a. Wash the threads and contact
surfaces of the bolts, the contact
surfaces of the plain washers, the
contact surface of the cylinder
head, and the threads of the
crankcase.
b. Apply the molybdenum disulfide
grease on the threads and con-
tact surfaces of the bolts and on
both contact surfaces of the plain
washers.
c. Install the plain washers and
bolts.
d. Tighten the bolts to the specified
torque in two or three steps in the
proper tightening sequence as
shown.e. Remove the bolts.
f. Again apply the molybdenum dis-
ulfide grease on the threads and
contact surfaces of the bolts and
on both contact surfaces of the
plain washers.
g. Retighten the bolts.
Tighten the bolts to the specified
torque in two or three steps in the
proper tightening sequence as
shown.
h. Put a mark on the corner "1" of the
bolt (cylinder head) and the cylin-
der head "2" as shown.
Tighten the bolts 90° in each of the
two steps to reach the specified angle
of 180° in the proper tightening se-
quence as shown.
Cylinder head warpage:
Less than 0.05 mm
(0.002 in)
Bolts (cylinder head):
1st:
30 Nm (3.0 m•kg, 22
ft•lb)
Bolts (cylinder head):
2nd:
20 Nm (2.0 m•kg, 14
ft•lb)
Bolts (cylinder head):
Final:
Specified angle 180°

5-25
VALVES AND VALVE SPRINGS
3. Inspect:• Valve facePitting/wear →Grind the face.
• Valve stem end
Mushroom shape or diameter
larger than the body of the stem →
Replace.
4. Measure: • Margin thickness "a"Out of specification →Replace.
5. Measure: • Runout (valve stem)
Out of specification →Replace.
• When installing a new valve always
replace the guide.
• If the valve is removed or replaced always replace the oil seal.
6. Eliminate:• Carbon deposits
(from the valve face and valve
seat)
7. Inspect:
• Valve seatPitting/wear →Reface the valve
seat.
8. Measure: • Valve seat width "a"Out of specification →Reface the
valve seat.
Measurement steps:
a. Apply Mechanic's blueing dye (Dykem) "b" to the valve face.
b. Install the valve into the cylinder head.
c. Press the valve through the valve
guide and onto the valve seat to
make a clear pattern.
d. Measure the valve seat width.
Where the valve seat and valve
face made contact, blueing will
have been removed.
e. If the valve seat is too wide, too narrow, or the seat is not cen-
tered, the valve seat must be
refaced.
9. Lap: • Valve face
• Valve seat
This model uses titanium intake
and exhaust valves. Titanium
valves that have been used to lap
the valve seats must not be used.
Always replace lapped valves with
new valves.
• When replacing the cylinder head, replace the valves without lapping
the valve seats and valve faces. • When replacing the valves or valve
guides, use new valves to lap the
valve seats, and then replace them
with new valves.
Lapping steps:
a. Apply a coarse lapping compound to the valve face.
Do not let the co mpound enter the
gap between the valve stem and
the guide.
b. Apply molybdenum disulfide oil to
the valve stem.
c. Install the valve into the cylinder head.
d. Turn the valve until the valve face
and valve seat are evenly pol-
ished, then clean off all of the
compound.
For best lapping results, lightly tap
the valve seat while rotating the valve
back and forth between your hands.
e. Apply a fine lapping compound to the valve face and repeat the
above steps.
After every lapping operation be sure
to clean off all of the compound from
the valve face and valve seat.
f. Apply Mechanic's blueing dye (Dykem) to the valve face.
g. Install the valve into the cylinder
head.
Margin thickness:
Intake:1.0 mm (0.039 in)
:0.85 mm
(0.033 in)
Exhaust: 1.0 mm (0.039 in)
:0.85 mm
(0.033 in)
Runout limit: 0.01 mm (0.0004 in)
Valve seat width:Intake:0.9–1.1 mm
(0.0354–0.0433 in)
:1.6 mm
(0.0630 in)
Exhaust: 0.9–1.1 mm
(0.0354–0.0433 in)
:1.6 mm
(0.0630 in)

5-26
VALVES AND VALVE SPRINGS
h. Press the valve through the valve
guide and onto the valve seat to
make a clear pattern.
i. Measure the valve seat width
again. If the valve seat width is out
of specification, reface and relap
the valve seat.
CHECKING THE VALVE SPRINGS
1. Measure:
• Valve spring free length "a"
Out of specification→Replace.
2. Measure:
• Compressed spring force "a"
Out of specification→Replace.
b. Installed length
3. Measure:
• Spring tilt "a"
Out of specification→Replace.CHECKING THE VALVE LIFTERS
1. Inspect:
• Valve lifter
Scratches/damage→Replace
both lifters and cylinder head.
INSTALLING THE VALVES
1. Apply:
• Molybdenum disulfide oil
Onto the valve stem and valve
stem seal.
2. Install:
• Valves "1"
• Valve spring seats "2"
• Valve stem seals "3"
• Valve springs "4"
• Valve spring retainers "5"
• Make sure that each valve is in-
stalled in its original place, also re-
ferring to the painted color as
follows.
Intake (middle) "a": blue
Intake (right/left) "b": gray
Exhaust "c": brown
• Install the valve springs with the
larger pitch "d" facing upward.
e. Smaller pitch
3. Install:
• Valve cotters
While compressing the valve spring
with a valve spring compressor "1" in-
stall the valve cotters.
4. To secure the valve cotters onto
the valve stem, lightly tap the
valve tip with a piece of wood.
Hitting the valve tip with excessive
force could damage the valve.
5. Install:
• Adjusting pad "1"
• Valve lifter "2"
• Apply the molybdenum disulfide oil
on the valve stem end.
• Apply the engine oil on the valve lift-
ers.
• Valve lifter must turn smoothly
when rotated with a finger.
• Be careful to reinstall valve lifters
and pads in their original place.
Free length (valve
spring):
Intake:
39.46 mm (1.55 in)
: 38.46 mm
(1.51 in)
Exhaust:
37.61 mm (1.48 in)
: 36.61 mm
(1.44 in)
Compressed spring
force:
Intake:
130.2–149.8 N at 27.87
mm (13.28–15.28 kg at
27.87 mm, 29.27–
33.68 lb at 1.10 in)
Exhaust:
123.1–141.7 N at 28.38
mm (12.55–14.45 kg at
28.38 mm, 27.67–
31.85 lb at 1.12 in)
Spring tilt limit:
Intake:
2.5°/1.7 mm (0.067 in)
Exhaust:
2.5°/1.6 mm (0.063 in)
Valve spring compres-
sor:
YM-4019/90890-04019