stop start YAMAHA YFZ50 2018 Owners Manual

EBU17421
TABLE OF CONTENTS
LOCATION OF THE WARNING AND
SPECIFICATION LABELS .............................. 1-1
SAFETY INFORMATION ................................ 2-1
DESCRIPTION................................................ 3-1Left view ...................................................... 3-1
Right view.................................................... 3-1
Controls and instruments............................ 3-2
INSTRUMENT AND CONTROL
FUNCTIONS ................................................... 4-1 Main switch ................................................. 4-1
Handlebar switches .................................... 4-1
Engine stop switch with lanyard ................. 4-2
Throttle lever ............................................... 4-3
Speed limiter ............................................... 4-3
Front brake lever ......................................... 4-5
Rear brake lever .......................................... 4-6
Parking brake .............................................. 4-6
Kickstarter ................................................... 4-7
Fuel tank cap .............................................. 4-8
Fuel ............................................................. 4-8
Fuel cock................................................... 4-10 Starter (choke) ......................................... 4-11
Seat .......................................................... 4-12
Adjusting the rear shock absorber ........... 4-13
PRE-OPERATION CHECKS .......................... 5-1 Fuel ............................................................. 5-3
Engine oil .................................................... 5-3
Transmission oil .......................................... 5-3
Front and rear brakes ................................. 5-3
Throttle lever ............................................... 5-3
Drive chain .................................................. 5-3
Tires ............................................................ 5-3
Chassis fasteners ....................................... 5-6
Instruments and switches........................... 5-6
OPERATION .................................................. 6-1 Starting a cold engine................................. 6-1
Starting a warm engine............................... 6-3
Engine break-in........................................... 6-3
Parking........................................................ 6-3
Parking on a slope ...................................... 6-4
Accessories and loading ............................ 6-5UBW461E0.book Page 1 Tuesda y, January 31, 2017 5:13 PM

2-4
2In the event of an accident
1. If serious injuries are incurred, you may be safer staying next to your vehicle; it may
shield you from oncoming riders. Depending
on your injuries and position in the trail; you
must make a judgment call as to whether you
should move to a position off the trail. If you
have sustained head, neck, or back injuries,
or cannot feel your limbs, you should not
move. Keep your helmet on and remain mo-
tionless. Lie down next to your vehicle and
wait for help.
2. If less serious injuries are incurred and you can walk, then move to a position off the trail.
Check yourself for injuries and apply first aid
as needed.
3. If your injuries are light, when safe to do so, move your vehicle off the trail to avoid colli-
sions with oncoming riders. Check for injuries
and apply first aid as necessary. If you can
physically operate your vehicle, inspect your
vehicle. If the vehicle is in safe operating con-
dition and you can safely operate it, restart it
and ride gently back to camp or other known
location where you can receive medical at- tention. If necessary, contact your riding party
or local authorities to let them know where
you are and what has happened.
In the event of a breakdown 1. If your vehicle will not restart or is not in safe operating condition, turn off the main switch
and engine stop switch. If the breakdown oc-
curs at twilight or night, leave the main switch
on so that your lights may warn other riders of
your stopped vehicle.
2. Get out of danger. Check for oncoming vehi- cles and when safe, push your vehicle to the
side of the trail or even off the main trail to
avoid any possible collisions with oncoming
riders. If you cannot move your vehicle by
yourself, when safe, walk to the nearest van-
tage point and signal an oncoming rider to
help you push your vehicle to a safe place off
the trail.
3. Inspect your vehicle for any immediate haz- ardous conditions. The most obvious hazard-
ous conditions are leaking fuel and
ungrounded or broken wiring. Visually check
for broken wiring and leaking fuel. Leaking
fuel can be confirmed by the odor of gasoline.
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2-5
2
4. Once immediate safety hazards are con-
firmed not to exist, you may remove your hel-
met to more closely inspect your vehicle.
Check for external signs of wear, broken
parts, fluid leaks, cracks in the frame, sus-
pension damage, wheel damage, and so on.
Fuel, oil, and coolant usually give off a notice-
able odor.
5. If your vehicle will not restart or if it is unsafe to ride, then turn off all vehicle systems (en-
gine stop switch, main switch, and fuel cock),
and then signal or go for help.
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 vehicle 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
guidelines in mind, as well as those found in the Loading section (page 6-6) when mounting acces-
sories.

Never install accessories that would impair the
performance of your ATV. Carefully inspect the
accessory before using it to make sure that it
does not in any way reduce ground clearance,
limit suspension travel, steering travel or control
operation.
 Accessories fitted to the ATV can create insta-
bility due to improper weight distribution.
 Bulky or large accessories may seriously affect
the stability of the ATV.
 Certain accessories can displace the operator
from his or her normal riding position. This im-
proper position limits the freedom of movement
of the operator and may limit control ability,
therefore, such accessories are not recom-
mended.
 Use caution when adding electrical accesso-
ries. If electrical accessories exceed the capac-
ity of the ATV’s electrical system, an electric
failure could result, which could cause a dan-
gerous loss of lights or engine power. Also, the
battery tends to discharge more quickly if elec-
trical accessories are added.
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2-7
2
Choose an appropriate riding area
Select an area appropriate for your child to learn
to ride. (See page 7-9.) 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 4-3.) 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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3-1
3
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 spring preload adjuster
6. Kickstarter lever cap
7. Throttle stop screw
12
4
5
3
6
7
1. Spark arrester
2. Owner’s tool kit
3. Fuse
4. Battery
5. Spark plug
6. Engine oil filler cap
7. Transmission oil filler cap
12
3,4
5
67
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4-1
4
EBU17738
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.
EBU18066Handlebar 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 “ / ”
2. Start switch “ ”
21
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4-2
4
EBU18102Start switch “ ”
Push this switch to crank the engine with the start-
er. See the starting instructions on page 6-1 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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6-1
6
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 6-3
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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6-3
6
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.EBU36860Engine break-inTIP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 240 km (150 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 240 km (150 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. 0–120 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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7-13
7
This procedure should be practiced at slow speed
many times in a large unpaved area with no obsta-
cles. If an incorrect technique is used, your ATV
may continue to go straight. If the ATV doesn’t
turn, come to a stop and then practice the proce-
dure again. If the riding surface is slippery or
loose, it may help to position more of your weight
over the front wheels by moving forward on the
seat. Once you have learned this technique, you should
be able to perform it at higher speeds or in tighter
curves.
Improper riding procedures such as abrupt throt-
tle changes, excessive braking, incorrect body
movements, or too much speed for the sharpness
of the turn may cause the ATV to tip. If the ATV be-
gins to tip over to the outside while negotiating a
turn, lean more to the inside. It may also be nec-
essary to gradually let off on the throttle and steer
to the outside of the turn to avoid tipping over.
Remember: Avoid higher speeds until you are
thoroughly familiar with the operation of your ATV.
CLIMBING UPHILL
WARNING
EWB01672Climbing hills improperly can cause overturns
or loss of control. Use proper riding techniques
described in this Owner’s Manual.

Never operate the ATV on hills too steep for
the ATV or for your abilities. The ATV can
overturn more easily on extremely steep hills
than on level surfaces or small hills.
 Always check the terrain carefully before you
start up any hill. Never climb hills with exces-
sively slippery or loose surfaces.
1. Lean towards inside of turn.
2. Support your weight on the outer footboard.
1
2
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