YAMAHA YFZ450 2012 Workshop Manual

6-2
6
Ambient temp./starter (choke) position
6. Completely close the throttle lever and start the engine by pushing the start switch.
TIPIf the engine fails to start, release the start switch,
then push it again. Pause a few seconds before
the next attempt. Each cranking should be as short as possible to preserve battery energy. Do not
crank the engine more than 10 seconds on each
attempt.
7. If the engine is started with the starter (choke)
in position (1), the starter (choke) should be
returned to position (2) to warm up the engine.
If the engine is started with the starter (choke)
in position (2), keep the starter (choke) in this
position to warm up the engine.
8. Continue warming up the engine until it idles smoothly, then return the starter (choke) to
position (3) before riding.TIPThe engine is warm when it responds quickly to the
throttle with the starter (choke) turned off.NOTICEECB00163For maximum engine life, never accelerate
hard when the engine is cold!
1. Fully open
2. Half open
3. Closed
4. Starter (choke)
1 2 3
12
3
4
U1PD60E0.book Page 2 Monday, June 13, 2011 2:57 PM

6-3
6
EBU20291Starting a warm engine Follow the same procedure as for starting a cold
engine, with the exception that the starter (choke)
is not required when the engine is warm. Instead,
start the engine with the throttle slightly open.EBU20522Shifting This ATV has a 5-speed forward transmission. The
transmission allows you to control the amount of
power you have available at a given speed or for
starting, accelerating, climbing hills, etc.
To shift into neutral, release the throttle lever, ap-
ply the clutch, and then repeatedly depress the
shift pedal until it stops.
When it stops, it will be in first gear. Raise the pedal
slightly to reach the neutral position, and then re-
lease the clutch.
EBU20592To start out and accelerate1. Release the throttle lever, apply the front or rear brake, and then release the parking
brake.NOTICEECB00200Always close the throttle before shifting gears,
otherwise damage to the engine and drive train
may result.2. Pull the clutch lever to disengage the clutch.1. Shift pedal
2. Neutral position
1
2
U1PD60E0.book Page 3 Monday, June 13, 2011 2:57 PM

6-4
6
3. Shift into first gear, and then release the
brake.
4. Open the throttle gradually and at the same time, release the clutch lever slowly.
WARNING! Opening the throttle abruptly or releasing the clutch lever too quickly
could make the ATV wheelie, which would
increase the chance of an accident, includ-
ing an overturn.
[EWB00731]
5. Once the ATV has attained adequate speed, release the throttle, and at the same time,
quickly pull in the clutch lever.
6. Shift the transmission into second gear. (Make sure not to shift the transmission into
neutral.)
7. Open the throttle part way and gradually re- lease the clutch lever.
8. Follow the same procedure when shifting to the next higher gear.EBU20650To decelerate
When slowing down or stopping, release the throt-
tle and apply the brakes smoothly and evenly. As
you slow down, shift to a lower gear. Be sure that
the engine has sufficiently slowed before engaging a lower gear. Improper use of the brakes or shifting
can cause the tires to lose traction, reducing con-
trol and increasing the possibility of an accident.
WARNING
EWB00710Make sure the engine has sufficiently slowed
before shifting to a lower gear. Engaging a low-
er gear when the engine speed is too high
could make the wheels stop rotating and lose
traction. This could cause loss of control, an
accident and injury. It could also cause engine
or drive train damage.NOTICEECB00180
Even with the transmission in the neutral po-
sition, do not coast for long periods of time
with the engine off, and do not tow the ATV
for long distances. The transmission is prop-
erly lubricated only when the engine is run-
ning. Inadequate lubrication may damage
the transmission.
U1PD60E0.book Page 4 Monday, June 13, 2011 2:57 PM

6-5
6

Always use the clutch when changing gears.
The engine, transmission and drive train are
not designed to withstand the shock of
forced shifting and can be damaged by shift-
ing without using the clutch.EBU20672Engine break-in TIP
For ATVs equipped with an odometer or an hour
meter, follow the figures given in km (mi) or the
figures given in hours.
For ATVs not equipped with an odometer or
hour meter, follow the figures given in hours.There is never a more important period in the life of
your engine than the first 320 km (200 mi) or 20
hours of riding. For this reason, you should read
the following material carefully.
Since the engine is brand new, do not put an ex-
cessive load on it for the first 320 km (200 mi) or 20
hours. The various parts in the engine wear and
polish themselves to the correct operating clear-
ances. During this period, prolonged full-throttle
operation or any condition that might result in en-
gine overheating must be avoided.0
–160 km (0 –100 mi) or 0 –10 hours
Avoid prolonged operation above 1/2 throttle. Vary
the speed of the ATV regularly. Do not operate it at
one set throttle position.
160 –320 km (100 –200 mi) or 10 –20 hours
Avoid prolonged operation above 3/4 throttle. Rev
the engine through the gears freely, but do not use
full throttle at any time.
320 km (200 mi) or 20 hours and beyond
The ATV can now be operated normally.
NOTICEECB00220If any engine trouble should occur during the
engine break-in period, immediately have a
Yamaha dealer check the ATV.EBU20722Parking When parking the ATV, shift into first gear, stop the
engine, apply the parking brake, and then turn the
fuel cock to “OFF ”.
U1PD60E0.book Page 5 Monday, June 13, 2011 2:57 PM

6-6
6
EBU20865Parking on a slope
WARNING
EWB00851Avoid parking on hills or other inclines. Park-
ing on a hill or other incline could cause the
ATV to roll out of control, increasing the
chance of an accident. If you must park on an
incline, place the ATV transversely across the
incline, shift into first gear, stop the engine, ap-
ply the parking brake, and then block the front
and rear wheels with rocks or other objects.Never park the ATV on hills that are too steep
to walk up easily.
1. Bring the ATV to a stop by applying the front
brake, shift into first gear, and then stop the
engine.
2. With the front and rear brakes applied, apply the parking brake.
3. Release the front and rear brakes.
4. Turn the fuel cock to “OFF ”.
1. Parking brake lever (locked position)U1PD60E0.book Page 6 Monday, June 13, 2011 2:57 PM

6-7
6
EBU20910Accessories and loading EBU20921Genuine Yamaha Accessories
Choosing accessories for your ATV is an important
decision. Genuine Yamaha Accessories, which
are available only from a Yamaha dealer, have
been designed, tested, and approved by Yamaha
for use on your ATV. Many companies with no con-
nection to Yamaha manufacture parts and acces-
sories or offer other modifications for Yamaha
vehicles. Yamaha is not in a position to test the
products that these aftermarket companies pro-
duce. Therefore, Yamaha can neither endorse nor
recommend the use of accessories not sold by
Yamaha or modifications not specifically recom- mended by Yamaha, even if sold and installed by
a Yamaha dealer.
Aftermarket parts, accessories, and modifica-
tions
While you may find aftermarket products similar in
design and quality to genuine Yamaha Accesso-
ries, recognize that some aftermarket accessories
or modifications are not suitable because of poten-
tial safety hazards to you or others. Installing after- market products or having other modifications
performed to your ATV that change any of the ve-
hicle
’s design or operation characteristics can put
you and others at greater risk of serious injury or
death. You are responsible for injuries related to
changes in the vehicle.
Keep the following in mind when considering an
accessory or operating an ATV which has acces-
sories.

Accessories should be rigidly and securely
mounted. An accessory which can shift position
or come off while you are riding could affect your
ability to control the ATV.
Do not mount an accessory where it could inter-
fere with your ability to control the ATV. Exam-
ples include (but are not limited to) a heavy or
bulky object attached to the handlebars which
could make steering difficult, an accessory that
limits your ability to move around on the seat, or
one that limits your view.
Use extra caution when riding an ATV with ac-
cessories. The ATV may handle differently than
it does without accessories.
U1PD60E0.book Page 7 Monday, June 13, 2011 2:57 PM

6-8
6
EBU20941Loading
WARNING
EWB00820Never exceed the stated load capacity for this
ATV. Overloading this ATV or carrying or tow-
ing cargo improperly could cause changes in
ATV handling which could lead to an accident.
Cargo should be properly distributed and se-
curely attached. Reduce speed when carrying
cargo or pulling a trailer. Allow greater dis-
tance for braking.As originally equipped, this ATV is not designed to
carry cargo or tow a trailer. If you choose to add ac-
cessories so that you can carry cargo or tow a trail-
er, you must use common sense and good
judgment as the stability and handling of an ATV
can be changed. When adding accessories, keep
the following points in mind:
Never exceed the weight limits shown. An over-
loaded ATV can be unstable.

If you are carrying cargo and towing a trailer, in-
clude the tongue weight in the maximum ATV
load limit.
Load cargo on the carriers as close to the center
of the ATV as possible. Put cargo at the rear of
the front carrier, at the front of the rear carrier,
and center it.
Tie down cargo securely to the carriers. Make
sure cargo in the trailer cannot move around. A
shifting load can cause an accident.
Make sure the load does not interfere with con-
trols or your ability to see where you are going.
Ride more slowly than you would without a load.
The more weight you carry, the slower you
should go. Although conditions vary, it is good
practice not to exceed 2nd gear whenever you
are carrying heavier loads or when towing a trail-
er.
Allow more braking distance. A heavier ATV
takes longer to stop.
Avoid making sharp turns unless at very slow
speeds.
Avoid hills and rough terrain. Choose terrain
carefully. Added weight affects the stability and
handling of the ATV.
MAXIMUM LOADING LIMIT
ATV loading limit (total weight of rider, cargo,
accessories, and tongue):100.0 kg (220 lb)
U1PD60E0.book Page 8 Monday, June 13, 2011 2:57 PM

7-1
7
EBU21141
RIDING YOUR ATV
U1PD60E0.book Page 1 Monday, June 13, 2011 2:57 PM

7-2
7
EBU21617GETTING TO KNOW YOUR ATV
This ATV is intended for recreational use by expe-
rienced operators only. This section, Riding your
ATV, provides general ATV riding instructions for
recreational riding. The skills and techniques de-
scribed in this section, however, are appropriate
for all types of riding. Riding your ATV requires
special skills acquired through practice over a pe-
riod of time. Take the time to learn the basic tech-
niques well before attempting more difficult
maneuvers.
Riding your new ATV can be a very enjoyable ac-
tivity, providing you with hours of pleasure. But it is
essential to familiarize yourself with the operation
of the ATV to achieve the skill necessary to enjoy
riding safely. Before you begin to ride, be sure you
have read this Owner’s Manual completely and un-
derstand the operation of the controls. Pay partic-
ular attention to the safety information on pages
2-1– 2-4. Also read all warning and notice labels on
your ATV. RIDE WITH CARE AND GOOD JUDGMENT
Get training if you are inexperienced.
WARNING
EWB01381
Do not operate this ATV or allow anyone else
to operate it without proper instruction. The
risk of an accident is greatly increased if the
operator does not know how to operate the
ATV properly in different situations and on
different types of terrain.
Do not operate this ATV at speeds too fast
for your skills or the conditions, as this in-
creases your chances of losing control of
the ATV and an accident. Always go at a
speed that is proper for the terrain, visibility
and operating conditions, and your experi-
ence.Beginning and inexperienced operators should
regularly practice the skills and the operating tech-
niques described in this Owner
’s Manual.
U1PD60E0.book Page 2 Monday, June 13, 2011 2:57 PM

7-3
7Riding your ATV requires skills acquired
through practice over a period of time.
Do not attempt to operate at maximum perfor-
mance until you are totally familiar with the ATV
’s
handling and performance characteristics. Take
the time to learn the basic techniques well before
attempting more difficult maneuvers. Become fa-
miliar with this ATV at slow speeds first, even if you
are an experienced operator.
Not recommended for children under 16 years
of age.
WARNING
EWB01390A child under 16 should never operate an ATV
with engine size greater than 90 cc. Use by chil-
dren of ATVs that are not recommended for
their age can lead to severe injury or death of
the child.
This ATV is designed to carry the operator only
– passengers prohibited.
The long seat is to allow the operator to shift posi-
tion as needed during operation. It is not for carry-
ing passengers. WARNING! Never carry a
passenger. Carrying a passenger on this ATV
greatly reduces your ability to balance and
control this ATV. You could have an accident,
resulting in severe injury or death to you
and/or your passenger.
[EWB01401]
U1PD60E0.book Page 3 Monday, June 13, 2011 2:57 PM