2021 YAMAHA YFZ50 Owners Manual

3-6
3
TEACHING YOUR CHILD TO OPERATE THE
ATV
WARNING
EWB00081Never let your child ride an ATV without close
adult supervision (a child under 6 should not
ride this ATV even with adult supervision).
Promptly correct your child if he or she begins
to ride beyond his or her abilities and, if neces-
sary, intervene by pulling the cord (lanyard) to
stop the engine.
If the child rides beyond his or her abilities, or
rides in terrain that is too difficult, he or she
may lose control of the ATV, causing an acci-
dent.
Introduce new riding areas slowly and make
sure the riding area matches your child’s skill
level. You must make the commitment to your child’s
proper use of the ATV. Your child must rely upon
you to be sure he or she has the development,
proper training, and proper equipment, as well as
an appropriately sized ATV and an appropriate rid-
ing area. Be sure your child is ready to learn how to ride
As a parent, your first step is to decide when your
child has the strength, skills, and judgment to
learn how to operate an ATV safely. Re-evaluate
your child’s readiness before every use; a child
who is too tired or distracted should not be al-
lowed to operate the ATV.
Be sure your child is properly trained
Your child should take a certified training course.
Training will continue with you as the instructor, so
you should be sure you thoroughly understand
proper riding techniques before continuing to in-
struct your child. Go through this Owner’s Manual
page by page with your child and be sure he or
she understands how to operate the ATV properly.
Be sure your child is wearing all the proper
safety equipment
Your child must always wear an approved motor-
cycle helmet that fits properly. Your child should
also wear the safety equipment described in the
Riding Your ATV section of this manual.UBW464E0.book Page 6 Thursday, January 23, 2020 2:42 PM

3-7
3Choose an appropriate riding area
Select an area appropriate for your child to learn
to ride. (See page 8-9.) Follow the instructions in
the Riding Your ATV section of this manual.
Choose a large, flat, unpaved road or area that is
free of obstacles and away from other vehicles.
Supervise every use of the ATV
Because an adult must supervise every ATV oper-
ator under age 16, you should closely watch your
child every time he or she uses the ATV. Be ready
to intervene immediately if the child is not operat-
ing according to your guidelines. This ATV is fitted
with an engine stop switch cord (lanyard) device
that will let you stop the engine remotely as you
walk behind the vehicle.
ENGINE STOP SWITCH CORD
This model has an engine stop switch cord (lan-
yard) designed for use by an adult supervising the
child operating the ATV. When using the engine
stop switch cord, be sure the speed limiter on the
handlebar is adjusted and the engine speed limiter
plate is installed to limit the ATV to a walking
speed. (See page 5-3.) 1. Install the cap on the end of the engine stop
switch cord onto the engine shut-off switch
(white button).
2. Put your fingers in the loop at the other end of the cord.
3. As your child is riding, walk behind the ATV, closely watching his or her actions as well as
the path ahead.
4. If there is a potential hazard ahead or if your child is not riding correctly, pull firmly on the
cord (lanyard) to stop the engine. Because
the ATV will continue to roll for some dis-
tance, allow extra time and distance to pull
the cord before a potentially hazardous situa-
tion might be encountered.
When your child has developed sufficient skill to
no longer need you to follow with the cord, se-
curely tie up the cord. However, you must still
closely supervise your child at all times during ATV
operation.
TIPThe ATV will not start without the cap in place. Be
sure to remove the cord and store it in a safe place
to prevent operation of the ATV when you are not
around to supervise.
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3-8
3
WARNING
EWB00073Avoid Carbon Monoxide Poisoning
All engine exhaust contains carbon monoxide,
a deadly gas. Breathing carbon monoxide can
cause headaches, dizziness, drowsiness, nau-
sea, confusion, and eventually death.
Carbon Monoxide is a colorless, odorless,
tasteless gas which may be present even if you
do not see or smell any engine exhaust. Deadly
levels of carbon monoxide can collect rapidly
and you can quickly be overcome and unable
to save yourself. Also, deadly levels of carbon
monoxide can linger for hours or days in en-
closed or poorly ventilated areas. If you experi-
ence any symptoms of carbon monoxide
poisoning, leave the area immediately, get
fresh air, and SEEK MEDICAL TREATMENT.
Do not run engine indoors. Even if you try to
ventilate engine exhaust with fans or open
windows and doors, carbon monoxide can
rapidly reach dangerous levels.
 Do not run engine in poorly ventilated or par-
tially enclosed areas such as barns, garages,
or carports. 
Do not run engine outdoors where engine
exhaust can be drawn into a building through
openings such as windows and doors.

WARNING
EWB02592When transporting the ATV in another vehicle,
be sure it is kept upright and that the fuel cock
is in the “OFF” position. Otherwise, fuel may
leak out of the carburetor or fuel tank.
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4-1
4
EBU17681
DESCRIPTION
EBU17691Left view
EBU17701Right view
1. Fuel tank cap
2. Fuel cock
3. Air filter
4. Engine stop switch with cord (lanyard)
5. Rear shock absorber
6. Kickstarter lever cap
7. Throttle stop screw
12
4
5
3
6
7
1. Spark arrester
2. Reflector
3. Tool kit
4. Fuse
5. Battery
6. Spark plug
7. Engine oil filler cap
8. Transmission oil filler cap1
23
4,5
6
78
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4-2
4
EBU17715Controls and instruments1. Rear brake lever
2. Handlebar switches
3. Parking brake lock plate
4. Front brake lever
5. Throttle lever
6. Main switch
7. Starter (choke) lever
12376 54
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5-1
5
EBU17739
INSTRUMENT AND CONTROL FUNCTIONS
EBU33850Main switchThe positions of the main switch are as follows:
ON
All electrical systems are supplied with power, and
the engine can be started. The key cannot be re-
moved.
OFF
All electrical systems are off. The key can be re-
moved.
EBU18068Handlebar switchesEBU18081Engine stop switch “ / ”
Set this switch to “ ” before starting the engine.
The engine stop switch controls the ignition and
stops the engine when it is running. Use this
switch to stop the engine in an emergency situa-
tion. The engine will not start or run when this
switch is set to “ ”.
ON
OFF
1. Engine stop switch ´ L

5-2
5
EBU18102Start switch “ ”
Push this switch to crank the engine with the start-
er. See the starting instructions on page 7-1 prior
to starting the engine.EBU36341Engine stop switch with lanyardThe cap must be attached to the engine stop
switch for the engine to run.
The lanyard should be held by putting your fingers
in the loop as shown.Should the ATV be separated from the parent by a
distance longer than the lanyard length, the lan-
yard will pull out the cap and stop the engine.
For further explanation of this switch and the lan-
yard, see “TEACHING YOUR CHILD TO OPER-
ATE THE ATV” in the “SAFETY INFORMATION”
section.
TIP
The engine cannot be started with the cap re-
moved.
1. Engine stop switch
2. Cap
3. Lanyard12
3
1. Lanyard
1
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5-3
5
When your child has developed sufficient skill to
no longer need you to follow with the lanyard,
securely tie up the lanyard. However, you must
still closely supervise your child at all times dur-
ing ATV operation.
EBU18286Throttle leverPush the throttle lever to increase engine speed.
Spring tension returns the lever to the rest position
when released. Always check that the throttle le-
ver returns normally before starting the engine.
EBU36330Speed limiterYour ATV was delivered with two speed limiter de-
vices. A vehicle speed limiter adjusting screw and
a removable engine speed limiter plate. Yamaha
recommends that all beginning riders start off with
the vehicle speed limiter adjusting screw fully
turned in and the engine speed limiter plate in-
stalled to limit the amount of speed available while
they learn.
The vehicle speed limiter keeps the throttle from
fully opening, even when the throttle lever is
pushed to the maximum. The adjusting screw may
be gradually turned out as the beginner becomes
more familiar with operating the ATV. Parents
should decide when to adjust the ATV for more
power as their youngster’s riding skills improve.
Once the ATV rider can operate with skill at the top
speed permitted by adjusting the vehicle speed
limiter alone, the engine speed limiter plate can be
removed. Since removal of this plate will result in
a significant increase in power, turn the vehicle
speed limiter adjusting screw completely back in
again and adjust it out in stages as done previous-
ly.
1. Throttle lever
1
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