2007 YAMAHA WR 450F engine

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GEN
INFO
STARTING AND BREAK-IN
STARTING AND BREAK-IN
WARNING
Never start or run the engine in a closed
area. The exhaust fumes are poisonous;
they can cause loss of consciousness and
death in a very short time. Always operate
the machine in a well-ventilated area.
CAUTION:
The carburetor on this machine has a
built-in accelerator pump. Therefore,
when starting the engine, do not operate
the throttle or the spark plug will foul.
Unlike a two-stroke engine, this engine
cannot be kick started when the throttle is
open because the kickstarter may kick
back. Also, if the throttle is open the air/
fuel mixture may be too lean for the
engine to start.
Before starting the machine, perform the
checks in the pre-operation check list.
AIR FILTER MAINTENANCE
According to “AIR FILTER CLEANING” section
in the CHAPTER 3, apply the foam-air-filter oil
or its equivalent to the element. (Excess oil in
the element may adversely affect engine start-
ing.)
STARTING A COLD ENGINE
NOTE:
This model is equipped with an ignition circuit
cut-off system. The engine can be started
under the following conditions.
When the transmission is in neutral.
When the clutch is disengaged with the
transmission in any position. However, it is
recommended to shift into neutral before
starting the engine.
1. Inspect the coolant level.
2. Turn the fuel cock to “ON”.
3. Push the main switch to “ON”.
4. Shift the transmission into neutral.
5. Fully open the cold starter knob 1.
6. Start the engine by pushing the start switch
or by kicking the kickstarter.
1

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GEN
INFO
STARTING AND BREAK-IN
NOTE:
If the engine fails to start by pushing the start
switch, release the switch, wait a few seconds,
and then try again. Each starting attempt
should be as short as possible to preserve the
battery. Do not crank the engine more than
10 seconds on any one attempt. If the engine
does not start with the starter motor, try using
the kickstarter.
WARNING
If the starter motor will not turn when
pushing the start switch, stop pushing it
immediately and kick start the engine in
order to avoid the load on the motor.
Do not open the throttle while kicking the
kickstarter. Otherwise, the kickstarter
may kick back.
7. Return the cold starter knob to its original
position and run the engine at 3,000 ~
5,000 r/min for 1 or 2 minutes.
NOTE:
Since this model is equipped with an accelera-
tor pump, if the engine is raced (the throttle
opened and closed), the air/fuel mixture will be
too rich and the engine may stall. Also unlike a
two-stroke engine, this model can idle.
CAUTION:
Do not warm up the engine for extended
periods of time.

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GEN
INFO
STARTING AND BREAK-IN
STARTING A WARM ENGINE
Do not operate the cold starter knob and throt-
tle. Pull the hot starter lever 1 and start the
engine by pushing the start switch or by kick-
ing the kickstarter forcefully with a firm stroke.
As soon as the engine starts, release the hot
starter lever to close the air passage.
Restarting an engine after a fall
Pull the hot starter lever and start the engine.
As soon as the engine starts, release the hot
starter lever to close the air passage.
The engine fails to start
Pull the hot starter lever all the way out and
while holding the lever, kick the kickstarter 10
to 20 times to clear the engine.
Then, restart the engine.
Refer to “Restarting an engine after a fall”.
* Operate the throttle grip before kick starting.
CAUTION:
Observe the following break-in procedures
during initial operation to ensure optimum
performance and avoid engine damage.
Throttle
grip oper-
ation*Cold
starter
knobHot
starter
lever
Starting a cold engine
Air temperature = less than
5 °C (41 °F)Open 3 or
4 timesON OFF
Air temperature = more
than 5 °C (41 °F)None ON OFF
Air temperature (normal
temperature) = between
5°C (41°F) and 25 °C
(77°F)None ON/OFF OFF
Air temperature = more
than 25 °C (77 °F)None OFF OFF
Starting an engine after a long
period of timeNone ON OFF
Restarting a warm engine None OFF ON
Restarting an engine after a fall None OFF ON

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GEN
INFO
BREAK-IN PROCEDURES
1. Before starting the engine, fill the fuel tank
with the fuel.
2. Perform the pre-operation checks on the
machine.
3. Start and warm up the engine. Check the
idle speed, and check the operation of the
controls and the “ENGINE STOP” button.
Then, restart the engine and check its
operation within no more than 5 minutes
after it is restarted.
4. Operate the machine in the lower gears at
moderate throttle openings for five to eight
minutes.
5. Check how the engine runs when the
machine is ridden with the throttle 1/4 to 1/2
open (low to medium speed) for about one
hour.
6. Restart the engine and check the operation
of the machine throughout its entire operat-
ing range. Restart the machine and oper-
ate it for about 10 to 15 more minutes. The
machine will now be ready to race.
CAUTION:
After the break-in or before each race,
you must check the entire machine for
loose fittings and fasteners as per
“TORQUE-CHECK POINTS”.
Tighten all such fasteners as required.
When any of the following parts have
been replaced, they must be broken in.
CYLINDER AND CRANKSHAFT:
About one hour of break-in operation is
necessary.
PISTON, RING, VALVES, CAMSHAFTS
AND GEARS:
These parts require about 30 minutes of
break-in operation at half-throttle or less.
Observe the condition of the engine care-
fully during operation.
STARTING AND BREAK-IN

GEN
INFO
EINFAHRVORSCHRIFTEN
1. Vor dem Starten voll tanken.
2. Die “Routinekontrolle vor Fahrt-
beginn” ausführen.
3. Den Motor anlassen und einige
Minuten lang betreiben. Die Leer-
laufdrehzahl und die Funktion der
Bedienelemente einschließlich des
Motorstoppschalters “ENGINE
STOP” kontrollieren. Den Motor
erneut anlassen und innerhalb 5
Minuten dessen Funktion kontrol-
lieren.
4. Das Motorrad 5–8 Minuten lang
mit mäßigem Gas im unteren
Gangbereich betreiben.
5. Den Motorbetrieb bei 1/4 bis 1/2
geöffnetem Gasdrehgriff (niedri-
ger bis mäßiger Geschwindig-
keit) etwa eine Stunde lang
überwachen.
6. Den Motor erneut starten und
den gesamten Betriebsbereich
kontrollieren. Den Motor erneut
starten und weiter 10–15 Minu-
ten lang betreiben. Das Motorrad
ist nun rennfertig.
ACHTUNG:
Entsprechend dem Abschnitt
“ANZUGSDREHMOMENTE
KONTROLLIEREN”, nach dem
Einfahren sowie vor jedem Ren-
nen sämtliche Befestigungsele-
mente kontrollieren.
Befestigungselemente ggf. vor-
schriftsmäßig festziehen.
Folgende Bauteile müssen nach
dem Auswechseln eingefahren
werden.
ZYLINDER UND KURBEL-
WELLE:
Eine einstündige Einfahrzeit ein-
legen.
KOLBEN, KOLBENRINGE, VEN-
TILE, NOCKLENWELLEN UND
RITZEL:
Eine halbstündige Einfahrzeit
mit maximal halb geöffnetem
Gasdrehgriff einlegen. Den
Motorbetrieb gründlich überwa-
chen. PROCEDURE DE RODAGE
1. Avant de démarrer le moteur, faire
le plein du réservoir de carburant.
2. Effectuer les contrôles avant utilisa-
tion.
3. Mettre le moteur en marche et le
laisser chauffer. Contrôler le régime
de ralenti et le bon fonctionnement
des commandes et du bouton
“ENGINE STOP”. Redémarrer
ensuite le moteur et contrôler son
fonctionnement dans les 5 minutes
maximum qui suivent son redémar-
rage.
4. Rouler pendant cinq à huit minutes
sur les rapports inférieurs et à
régime modéré.
5. Contrôler le fonctionnement du
moteur lorsque la moto est utilisée
pendant une heure environ aux régi-
mes bas à moyens (ouverture des
gaz 1/4 à 1/2).
6. Remettre le moteur en marche et
vérifier le fonctionnement de la
moto à toutes les vitesses. Redémar-
rer la moto et rouler pendant 10 à 15
minutes environ. La moto est main-
tenant prête pour la course.
ATTENTION:
Après le rodage ou avant chaque
course, il est indispensable de con-
trôler le bon serrage des raccords et
des fixations conformément aux ins-
tructions de la section “POINTS DE
VERIFICATION DES COUPLES
DE SERRAGE”.
Resserrer au couple requis tout élé-
ment desserré.
Si l’une quelconque des pièces sui-
vantes a été remplacée, un nouveau
rodage est nécessaire.
CYLINDRE ET VILEBREQUIN:
Roder pendant environ une heure.
PISTON, SEGMENT, SOUPAPES,
ARBRES A CAMES ET
PIGNONS:
Ces pièces nécessitent un rodage
d’environ 30 minutes à une ouver-
ture des gaz de 1/2 au maximum.
Surveiller attentivement l’état du
moteur pendant le rodage.PROCEDIMIENTO DE RODAJE
1. Antes de poner en marcha el motor
llene el depósito de combustible.
2. Realice las comprobaciones previas
de la máquina.
3. Arranque y caliente el motor. Com-
pruebe el ralentí, así como el fun-
cionamiento de los mandos y el
botón “ENGINE STOP”. A conti-
nuación vuelva a arrancar el motor
y compruebe su funcionamiento
durante no más de 5 minutos des-
pués de arrancar.
4. Utilice la máquina en marchas cor-
tas y a regímenes moderados
durante cinco a ocho minutos.
5. Observe cómo funciona el motor
con el gas entre 1/4 y 1/2 (régimen
entre bajo y medio) durante aproxi-
madamente una hora.
6. Vuelva a arrancar el motor y com-
pruebe el funcionamiento de la
máquina en todos los regímenes.
Vuelva a arrancar la máquina y uti-
lícela durante 10 o 15 minutos más.
La máquina ya está preparada para
competir.
ATENCION:
Después del rodaje o antes de cada
carrera debe comprobar toda la
máquina para detectar piezas o
sujeciones flojas, conforme a “PUN-
TOS DE COMPROBACIÓN DE
APRIETE”.
Apriete todas las sujeciones según
sea necesario.
Las piezas siguientes, si se cambian,
deben pasar el rodaje.
CILINDRO Y CIGÜEÑAL:
Requieren aproximadamente una
hora de rodaje.
PISTÓN, ARO, VÁLVULAS, EJES
DE LEVAS Y ENGRANAJES:
Estas piezas requieren aproximada-
mente 30 minutos de rodaje a medio
gas o menos. Observe atentamente
el estado del motor durante el fun-
cionamiento.
MISE EN MARCHE ET RODAGE
STARTEN UND EINFAHREN
PUESTA EN MARCHA Y RODAJE
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GEN
INFO
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TORQUE-CHECK POINTS
TORQUE-CHECK POINTS
NOTE:
Concerning the tightening torque, refer to
“MAINTENANCE SPECIFICATIONS” section
in the CHAPTER 2.
Frame to rear frame
Fuel tank to frame
Silencer to rear frame
Frame to engine
Engine bracket to engine
Engine bracket to frame
Steering shaft to frame
Steering shaft to handle crown
Handle crown to handlebar
Front fork to handle crown
Front fork to under bracket
Assembly of links
Link to frame
Link to shock absorber
Link to swingarm
Shock absorber to frame
Tightening of pivot shaft
Tightening of front axle
Tightening of axle holder
Tightening of rear axle
Wheel to sprocket
Caliper to front fork
Brake disc to wheel
Tightening of union bolt
Master cylinder to handlebar
Tightening of air bleeder
Tightening of brake hose holder
Brake pedal to frame
Brake disc to wheel
Tightening of union bolt
Master cylinder to frame
Tightening of air bleeder
Tightening of brake hose holder
Fuel tank to fuel cock
Tightening of oil hose clamp Frame construction
Combined seat and tank
Exhaust system
Engine mounting
Steering Steering shaft to
handlebar
Suspension Front Steering shaft to front
fork
Rear For link type
Rear Installation of shock
absorber
Rear Installation of
swingarm
Wheel Installation of wheel Front
Rear
Brake Front
Rear
Fuel system
Lubrication system

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GEN
INFO
CLEANING AND STORAGE
EC1B0000
CLEANING AND STORAGE
EC1B1000
CLEANING
Frequent cleaning of your machine will
enhance its appearance, maintain good overall
performance, and extend the life of many com-
ponents.
1. Before washing the machine, block off the
end of the exhaust pipe to prevent water
from entering. A plastic bag secured with a
rubber band may be used for this purpose.
2. If the engine is excessively greasy, apply
some degreaser to it with a paint brush. Do
not apply degreaser to the chain, sprock-
ets, or wheel axles.
3. Rinse the dirt and degreaser off with a gar-
den hose; use only enough pressure to do
the job.
CAUTION:
Excessive hose pressure may cause water
seepage and contamination of wheel bear-
ings, front forks, brakes and transmission
seals. Many expensive repair bills have
resulted from improper high pressure
detergent applications such as those avail-
able in coin-operated car washers.
4. After the majority of the dirt has been
hosed off, wash all surfaces with warm
water and a mild detergent. Use an old
toothbrush to clean hard-to-reach places.
5. Rinse the machine off immediately with
clean water, and dry all surfaces with a soft
towel or cloth.
6. Immediately after washing, remove excess
water from the chain with a paper towel
and lubricate the chain to prevent rust.
7. Clean the seat with a vinyl upholstery
cleaner to keep the cover pliable and
glossy.

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GEN
INFO
CLEANING AND STORAGE
8. Automotive wax may be applied to all
painted or chromed surfaces. Avoid combi-
nation cleaner-waxes, as they may contain
abrasives.
9. After completing the above, start the
engine and allow it to idle for several min-
utes.
EC1B2001
STORAGE
If your machine is to be stored for 60 days or
more, some preventive measures must be
taken to avoid deterioration. After cleaning the
machine thoroughly, prepare it for storage as
follows:
1. Drain the fuel tank, fuel lines, and the car-
buretor float bowl.
2. Remove the spark plug, pour a tablespoon
of SAE 10W-30 motor oil in the spark plug
hole, and reinstall the plug. With the engine
stop switch pushed in, kick the engine over
several times to coat the cylinder walls with
oil.
3. Remove the drive chain, clean it thoroughly
with solvent, and lubricate it. Reinstall the
chain or store it in a plastic bag tied to the
frame.
4. Lubricate all control cables.
5. Block the frame up to raise the wheels off
the ground.
6. Tie a plastic bag over the exhaust pipe out-
let to prevent moisture from entering.
7. If the machine is to be stored in a humid or
salt-air environment, coat all exposed
metal surfaces with a film of light oil. Do not
apply oil to rubber parts or the seat cover.
NOTE:
Make any necessary repairs before the
machine is stored.