2017 YAMAHA YFZ50 parking brake

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
assembly ................................................ 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
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3-2
3
EBU17714Controls and instrumentsTIPThe ATV you have purchased may differ slightly
from the figures shown in this manual. 1. Rear brake lever
2. Handlebar switches
3. Parking brake lock plate
4. Front brake lever
5. Throttle lever
6. Main switch
7. Starter (choke)
12376 54
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4-6
4
EBU18402Rear brake leverThe rear brake lever is located on the left handle-
bar. To apply the rear brake, pull the brake lever
toward the handlebar grip.EBU18462Parking brakeUse the parking brake before starting the engine
or after parking the ATV, especially on a slope. Ap-
ply the rear brake lever and push down the lock
plate to apply the parking brake. Squeeze the rear
brake lever to release the parking brake.
WARNING
EWB00221Always set the parking brake before starting
the engine. The ATV could start moving un-
expectedly if the parking brake is not ap-
plied. This could cause loss of control or a
collision.
 Always be sure you have released the park-
ing brake before you begin to ride. The brake
could overheat if you ride the ATV without re-
leasing the parking brake. You could lose
1. Rear brake lever
1
1. Parking brake lock plate
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. EBU36360Starting 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. Use the starter (choke) in reference to the fi- gure:
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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6-2
6Ambient temp./starter (choke) position
5. Completely close the throttle lever and start the engine by pushing the start switch.
TIPIf 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 en-
ergy. Do not crank the engine more than 10 sec-
onds on each attempt. 
If the engine fails to start using the start switch,
try using the kickstarter. (See page 4-7.)
6. 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 en-
gine. If the engine is started with the starter
(choke) in position (2), keep the starter (choke)
in this position to warm up the engine.
7. 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. 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)
4
3
2
1
(1) (3)
(2)
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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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6-4
6
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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7-11
7
Do not ride in areas posted “no trespassing”.
Do not ride on private property without getting
permission. Select a large, flat, unpaved area to become famil-
iar with your ATV. Make sure that this area is free
of obstacles and other riders. You should practice
control of the throttle, brakes, and turning techni-
ques in this area before trying more difficult ter-
rain.
Set the parking brake and follow the instruction on
page 6-1 to start the engine. Once it has warmed
up you are ready to begin riding your ATV. Re-
member that the engine and exhaust pipe will be
hot when riding and afterwards; do not allow skin
or clothing to come in contact with these compo-
nents.
With the engine idling, release the parking brake.
Apply the throttle slowly and smoothly. You will
start to accelerate. If the throttle is applied too
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