2012 YAMAHA YZ450F service

OWNER’S SERVICE MANUALMANUEL D’ATELIER DU PROPRIETAIRE
FA\fRER- UND
WARTUNGS\fANDBUC\f
YZ450F (
B )
\b\bD-28199-82PRINTED IN JAPAN
2011.05—1.5 ×1 !
(E, F, \f)
PRINTED ON REC\bCLED PAPER
2012
YZ450F (
B )
2012
qRead this manual carefully before operating this vehicle.
qIl convient de lire attentivement ce manuel avant la première utilisation du véhicule.
qBitte lesen Sie diese Bedienungsanleitung sorgfältig durch, bevor Sie das Fahrzeug in Betrieb nehmen.
%@DPWFS




Ö”´


YZ450F(B)
OWNER'S SERVICE MANUAL
©2011 by Yamaha Motor Co., Ltd.
1st Edition, April 2011
All rights reserved. Any reprinting or
unauthorized use without the written
permission of Yamaha Motor Co., Ltd.
is expressly prohibited.
Printed in Japan

HOW TO READ DESCRIPTIONS
To help identify parts and clarify pro-
cedure steps, there are exploded dia-
grams at the start of each removal
and disassembly section.
1. An easy-to-see exploded diagram
"1" is provided for removal and
disassembly jobs.2. Numbers "2" are given in the or-
der of the jobs in the exploded di-
agram. A number that is enclosed
by a circle indicates a disassem-
bly step.
3. An explanation of jobs and notes
is presented in an easy-to-read
way by the use of symbol marks
"3". The meanings of the symbol
marks are given on the next page.4. A job instruction chart "4" accom-
panies the exploded diagram,
providing the order of jobs, names
of parts, notes in jobs, etc.
5. For jobs requiring more informa-
tion, the step-by-step format sup-
plements "5" are given in addition
to the exploded diagram and job
instruction chart.
ILLUSTRATED SYMBOLS (Refer to
the illustration)Illustrated symbols "1" to "7" are used
to identify the specifications appear-
ing in the text.
1. With engine mounted
2. Filling fluid
3. Lubricant
4. Special tool
5. Tightening
6. Specified value, Service limit
7. Resistance (Ω), Voltage (V),
Electric current (A)
Illustrated symbols "8" to "13" in the
exploded diagrams indicate grade of
lubricant and location of lubrication
point.
8. Apply engine oil
9. Apply molybdenum disulfide oil
10. Apply brake fluid
11. Apply lightweight lithium-soap
base grease
12. Apply molybdenum disulfide
grease13. Apply silicone grease
Illustrated symbols "14" to "15" in the
exploded diagrams indicate where to
apply a locking agent and where to in-
stall new parts.
14. Apply locking agent (LOC-
TITE
®)
15. Use new one
1
23
45

1-4
LOCATION OF IMPORTANT LABELS
Familiarize yourself with the following pictograms and read the explanatory text.
Read Owner's service manual.
This unit contains high-pressure nitrogen gas. Mishandling can cause explosion. Do not incinerate,
puncture or open.
Turn off the main switch after riding to avoid draining the battery.
Use unleaded gasoline only.
Measure tire pressure when tires are cold.
Adjust tire pressure.
Improper tire pressure can cause loss of control.
Loss of control can result in severe injury or death.

2-1
GENERAL SPECIFICATIONS
SPECIFICATIONS
GENERAL SPECIFICATIONS
Model name: YZ450FB (USA, CDN, AUS, NZ)
YZ450F (EUROPE, ZA)
Model code number: 33D9 (USA,CDN)
33DA (EUROPE)
33DC (AUS, NZ, ZA)
Dimensions: USA, CDN EUROPE AUS, NZ, ZA
Overall length 2,195 mm (86.42
in)2,191 mm (86.26
in)2,196 mm (86.46
in)
Overall width 825 mm (32.48 in)←←
Overall height 1,312 mm (51.65
in)1,311 mm (51.61
in)1,312 mm (51.65
in)
Seat height 999 mm (39.33 in)←998 mm (39.29 in)
Wheelbase 1,492 mm (58.74
in)1,487 mm (58.54
in)←
Minimum ground clearance 384 mm (15.12 in) 383 mm (15.08 in)←
Weight:
Curb weight 111 kg (245 lb)
Engine:
Engine type Liquid cooled 4-stroke, DOHC
Cylinder arrangement Single cylinder
Displacement 449.7 cm
3 (15.8 Imp oz, 15.2 US oz)
Bore × stroke 97.0 × 60.8 mm (3.82 × 2.39 in)
Compression ratio 12.5 : 1
Starting system Kickstarter
Lubrication system: Dry sump
Oil type or grade:
Engine oil
Recommended brand: YAMALUBE
SAE10W-30, SAE10W-40, SAE10W-50,
SAE15W-40, SAE20W-40 or SAE20W-50
API service SG type or higher,
JASO standard MA
Oil capacity:
Engine oil
Periodic oil change 0.95 L (0.84 Imp qt, 1.00 US qt)
With oil filter replacement 1.0 L (0.88 Imp qt, 1.06 US qt)
Total amount 1.2 L (1.06 Imp qt, 1.27 US qt)
Coolant capacity (including all routes): 1.13 L (0.99 Imp qt, 1.19 US qt)
Air filter: Wet type element
2

3-1
MAINTENANCE INTERVALS
REGULAR INSPECTION AND ADJUSTMENTS
MAINTENANCE INTERVALS
• 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..
ItemAfter
break-
inEvery
race
(about
2.5
hours)
Every
third
(about
7.5
hours)Every
fifth
(about
12.5
hours)
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●
VALVE LIFTERS
Inspect●Check for scratches and wear.
Replace●
CAMSHAFTS Inspect the camshaft surface.
Inspect●Inspect the decompression system.
Replace●
CAMSHAFT SPROCKETS
Inspect●Check for wear on the teeth and for
damage.
Replace●
PISTON
Inspect●Inspect crack.
Clean●Inspect carbon deposits and eliminate
them.
Replace●●Replace the piston, piston pin, piston
pin clip, and piston ring all as a set.
PISTON RING
Inspect●Check ring end gap.
Replace●●Replace the piston, piston pin, piston
pin clip, and piston ring all as a set.
PISTON PIN
Inspect●
Replace●●Replace the piston, piston pin, piston
pin clip, and piston ring all as a set.
3

3-10
ENGINE
CHANGING THE ENGINE OIL
1. Start the engine and let it warm up
for several minutes.
2. Stop the engine and place an oil
pan under the drain bolt.
3. Remove:
• Oil filler cap "1"
• Drain bolt (with gasket) "2"
• Drain bolt (with gasket) "3"
Drain the engine oil.
4. If the oil filter is to be replaced dur-
ing this oil change, remove the fol-
lowing parts and reinstall them.
Replacement steps:
a. Remove the oil filter element cov-
er "1" and oil filter element "2".
b. Check the O-rings "3", if cracked
or damaged, replace them with a
new one.
c. Install the oil filter element and oil
filter element cover.
5. Install:
• Gaskets
• Oil drain bolt (oil pan)
• Oil drain bolt (oil tank)
6. Fill:
• Engine oil
7. Install:
• Oil filler cap
8. Inspect:
• Engine (for oil leaks)
• Oil levelCHECKING THE OIL PRESSURE
1. Check:
• Oil pressure
Checking steps:
a. Slightly loosen the oil pressure
check bolt "1".
b. Start the engine and keep it idling
until oil starts to seep from the oil
pressure check bolt. If no oil
comes out after one minute, turn
the engine off so it will not seize.
c. Check oil passages and oil pump
for damage or leakage.
d. Start the engine after solving the
problem(s) and recheck the oil
pressure.
e. Tighten the oil pressure check
bolt.
ADJUSTING THE ENGINE IDLING
SPEED
• Because the air pressure is lower at
high altitudes, the air-fuel mixture
will become richer. If the engine
idling speed is low, turn the starter
(choke) knob/idling screw a few
clicks counterclockwise to increase
the idling speed.
• Before adjusting the engine idling
speed, make sure that the com-
pression pressure is within specifi-
cation and that the air filter element
is not clogged.
• Adjust the engine idling speed with
the starter (choke) knob/idling
screw pushed in completely.
1. Start the engine and warm it up
until the engine oil has reached
the specified temperature.
2. Use a temperature probe tester
"1" and contact it to the drain bolt
thread. Recommended brand:
YAMALUBE
Recommended engine
oil type
SAE10W-30, SAE 10W-
40, SAE10W-50, SAE
15W-40, SAE 20W-40 or
SAE 20W-50
Recommended engine
oil grade
API service SG type or
higher, JASO standard
MA
Oil filter element cover:
10 Nm (1.0 m•kg, 7.2
ft•lb)
Oil drain bolt (oil pan):
20 Nm (2.0 m•kg, 14
ft•lb)
Oil drain bolt (oil tank):
20 Nm (2.0 m•kg, 14
ft•lb)
Oil quantity:
Periodic oil change:
0.95 L (0.84 Imp qt,
1.00 US qt)
With oil filter replace-
ment:
1.0 L (0.88 Imp qt, 1.06
US qt)
Total amount:
1.2 L (1.06 Imp qt, 1.27
US qt)
Oil pressure check bolt:
10 Nm (1.0 m•kg, 7.2
ft•lb)
Oil temperature:
55.0–65.0 °C
(131–149°F)

3-11
ENGINE
3. Adjust:
• Engine idling speed
Adjustment steps:
a. Turn the starter knob/idle screw
"1" until the specified engine idling
speed is obtained.
Using the digital tachometer, mea-
sure the engine speed with the detec-
tor "c" pinched in the high tension
cord "2" of the ignition coil.
ADJUSTING THE VALVE
CLEARANCE
• This section is intended for those
who have basic knowledge and skill
concerning the servicing of Yama-
ha motorcycles (e.g., Yamaha deal-
ers, service engineers, etc.) Those
who have little knowledge and skill
concerning servicing are requested
not to undertake inspection, adjust-
ment, disassembly, or reassembly
only by reference to this manual. It
may lead to servicing trouble and
mechanical damage.
• The valve clearance should be ad-
justed when the engine is cool to
the touch.
1. Remove:
•Seat
Refer to "SEAT AND SIDE COV-
ERS" section in the CHAPTER 4.
•Fuel tank
Refer to "FUEL TANK" section in
the CHAPTER 6.
2. Remove:
• Spark plug
• Cylinder head cover
Refer to "CAMSHAFTS" section
in the CHAPTER 4.
3. Remove:
• Timing mark accessing screw "1"
• Crankshaft end accessing screw
"2"
• O-ring
4. Check:
• Valve clearance
Out of specification→Adjust.
Checking steps:
a. Turn the crankshaft counterclock-
wise with a wrench.
b. Align the alignment mark "a" on
the rotor with the alignment mark
"b" on the crankcase cover.
Make sure that the alignment mark
"c" on the exhaust camshaft sprocket
and the alignment mark "d" on the in-
take camshaft sprocket are aligned
with the edge of the cylinder head.
c. Measure the valve clearance "e"
using a feeler gauge "1".
Record the measured reading if the
clearance is incorrect.
Digital tachometer:
YU-39951-B/90890-
06760
To increase the engine idling
speed→Turn the starter
(choke) knob/idling screw
counterclockwise "a".
To decrease the engine idling
speed→Turn the starter
(choke) knob/idling screw
clockwise "b".
Engine idling speed:
1,900–2,100 r/min
Valve clearance (cold):
Intake valve:
0.10–0.15 mm
(0.0039–0.0059 in)
Exhaust valve:
0.20–0.25 mm
(0.0079–0.0098 in)