2021 YAMAHA YFZ50 Owners Manual

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EBU19841Chassis fastenersMake sure that all nuts, bolts and screws are
properly tightened.EBU33810Instruments and switchesCheck that all instruments and switches are work-
ing properly. Correct if necessary.UBW464E0.book Page 6 Thursday, January 23, 2020 2:42 PM

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EBU19882
OPERATION
EBU19902Read the Owner’s Manual carefully before riding
the ATV. If there is a control or function you do not
understand, ask your Yamaha dealer.
WARNING
EWB00632Read the Owner’s Manual carefully to become
familiar with all controls in order to help pre-
vent any loss of control, which could cause an
accident or injury. EBU36361Starting a cold engineNOTICEECB00151See the “Engine break-in” section on page 7-3
prior to operating the engine for the first time. 1. Set the parking brake. (The engine can bestarted only when the rear brake lever is ap-
plied.)
2. Turn the fuel cock to “ON”. 3. Turn the key to “ON” and set the engine stop
switch to “ ”.
4. Position the starter (choke) lever according to the ambient temperature.
Position (1):
Cold engine start with ambient temperature
below 5 °C (40 °F).
Position (2):
Cold engine start with ambient temperature
between 0 °C (30 °F) and 30 °C (90 °F).
Position (3):
Cold engine start with ambient temperature
above 25 °C (80 °F).
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Ambient temp./starter (choke) position
5. Release the throttle lever and start the engine by pushing the start switch.
TIPIf the engine fails to start, release the start
switch and pause a few seconds before the
next attempt. Prolonged cranking will drain bat-
tery energy. Do not crank the engine for more
than 10 seconds on any one attempt. 
If the engine fails to start using the start switch,
try using the kickstarter. (See page 5-7.)
6. If the engine is started with the starter (choke)
lever in position (1), move the lever to position
(2) to warm up the engine. If the engine is
started with the starter (choke) lever in posi-
tion (2), keep the lever in this position to warm
up the engine.
7. Continue warming up the engine until it idles smoothly, then return the starter (choke) lever
to position (3) before riding.TIPThe engine is warm when it responds quickly to
the throttle with the starter (choke) turned off. 8. Release the parking brake.NOTICEECB00164For maximum engine life, never accelerate
hard when the engine is cold!
1. Fully open
2. Half open
3. Closed
4. Starter (choke) lever
4
3
2
1
(1) (3)
(2)
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EBU20292Starting a warm engineFollow 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.EBU36861Engine break-inThere is never a more important period in the life
of your engine than the first 240 km (150 mi) or 20
hours of operation. For this reason, you should fol-
low the engine break-in instructions carefully.
Since the engine is brand new, do not put an ex-
cessive load on it for the first 240 km (150 mi) or
20 hours. During this period the various parts in
the engine wear and polish themselves to the cor-
rect operating clearances. Avoid prolonged full-
throttle operation or any condition that might re-
sult in engine overheating.
0–120 km (0–75 mi) or 0–10 hours
Avoid prolonged operation above 1/2 throttle.
Vary the speed of the ATV regularly. Do not oper-
ate it at one set throttle position.120–240 km (75–150 mi) or 10–20 hours
Avoid prolonged operation above 3/4 throttle. Rev
the engine freely, but do not use full throttle at any
time.
240 km (150 mi) or 20 hours and beyond
The ATV can now be operated normally.
NOTICEECB00221If any engine trouble should occur during the
engine break-in period, immediately have a
Yamaha dealer check the ATV. EBU36370ParkingWhen parking the ATV, apply the rear brake lever,
stop the engine, apply the parking brake, and then
turn the fuel cock to “OFF”.
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EBU36380Parking on a slope
WARNING
EWB04130Avoid parking on hills or other inclines. Parking
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, stop
the engine, apply 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
brakes.
2. Stop the engine.
3. With the rear brake lever applied, apply the parking brake, and then slowly release the
rear brake lever.
4. Turn the fuel cock to “OFF”.
1. Parking brake lock plate
1
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EBU20911Accessories and loadingEBU20922Genuine Yamaha Accessories
Choosing accessories for your ATV is an impor-
tant 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 connection to Yamaha manufacture parts
and accessories or offer other modifications for
Yamaha vehicles. Yamaha is not in a position to test the products that these aftermarket compa-
nies produce. Therefore, Yamaha can neither en-
dorse nor recommend the use of accessories not
sold by Yamaha or modifications not specifically
recommended by Yamaha, even if sold and in-
stalled 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 po-
tential safety hazards to you or others. Installing aftermarket products or having other modifica-
tions performed to your ATV that change any of
the vehicle’s design or operation characteristics
can put you and others at greater risk of serious
injury or death. You are responsible for injuries re-
lated 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.UBW464E0.book Page 5 Thursday, January 23, 2020 2:42 PM

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EBU33880Loading
WARNING
EWB00821Never 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
accessories so that you can carry cargo or tow a
trailer, 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.
 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, car-
go, accessories, and tongue weight):41.0 kg (90 lb)UBW464E0.book Page 6 Thursday, January 23, 2020 2:42 PM

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EBU21142
RIDING YOUR ATV
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