2017 YAMAHA YFM90 engine

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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.
EBU17794Indicator lightsEBU17861Neutral indicator light “ ”
This indicator light comes on when the transmis-
sion is in the neutral position.EBU17831Reverse indicator light “ ”
This indicator light comes on when the transmis-
sion is in the reverse position.
ON
OFF
1. Reverse indicator light “R”
2. Neutral indicator light “N”
1
2
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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 “ ”.
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.EBU18283Throttle leverOnce the engine is running, pushing the throttle le-
ver will increase the engine speed.
Regulate the speed of the ATV by varying the
throttle position. Because the throttle is spring-
loaded, the ATV will decelerate, and the engine
will return to an idle any time the throttle lever is re-
leased.
1. Engine stop switch “ / ”
2. Start switch “ ”
21
1. Throttle lever
1
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4Before starting the engine, check the throttle to be
sure it is operating smoothly. Make sure it returns
to the idle position as soon as the lever is released.
EBU33801Speed 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.
Vehicle speed limiter
1. Loosen the locknut.
2. To increase the maximum engine power available and the maximum speed of the ATV,
turn the adjusting screw in direction (a). To
decrease the maximum engine power avail-
able and the maximum speed of the ATV, turn
the adjusting screw in direction (b). Do not
turn the adjusting screw out more than 10
mm (0.39 in) or the throttle cable could be
damaged. Always make sure the throttle lever
free play is adjusted to 1.5–4.0 mm (0.06–
0.16 in). (See page 8-20.) WARNING! Im-
proper adjustment of the speed limiter and
throttle could cause throttle cable damage
or improper throttle operation. You could
lose control, resulting in an accident.
[EWB00242]
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3. Tighten the locknut.
Engine speed limiter plate
When the engine speed limiter plate is installed,
engine speed is limited to 4900 r/min. When this
plate is removed, top engine speed (8500 r/min) is
available.
Remove the plate as follows. 1. Remove the seat. (See page 4-12.)
2. Loosen the screws, and then remove the plate as shown. 3. Tighten the screws.
4. Install the seat.
TIPStore the engine speed limiter plate with the own-
er’s manual so that it is readily available whenever
you want to reduce top engine speed. EBU18392Front brake leverThe front brake lever is located on the right han-
dlebar. To apply the front brake, pull the brake le-
ver toward the handlebar grip.
1. Locknut
2. Adjusting screw
3. No more than 10 mm (0.39 in)
1
3
2
(b)
(a)
1. Screw
2. Engine speed limiter plate
12
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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.
1. Front brake lever
1
1. Rear brake lever
1
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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 braking performance which could cause an
accident. You could also wear out the brakes
prematurely.
EBU18582Drive select leverThe drive select lever is used to shift your ATV into
the forward, neutral and reverse positions. See the
“Operating the drive select lever and driving in re-
verse” section on page 6-3 for the drive select le-
ver operation.
1. Parking brake lock plate
1
1. Drive select lever
1
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EBU33891KickstarterA kickstarter lever is located under the seat. (See
page 4-12.) Use the kickstarter to start the engine
if the battery is discharged.1. Remove the kickstarter lever cap. 2. Install the kickstarter lever.
3. Move the kickstarter lever down lightly with
your foot until the gears engage, and then
push it down smoothly but forcefully.1. Kickstarter lever
1
1. Kickstarter lever cap
1
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NOTICEECB02300Do not use the kickstarter if the battery is not
installed or if the battery leads are not connect-
ed. EBU18721Fuel tank capRemove the fuel tank cap by turning it counter-
clockwise.
EBU18757FuelMake sure there is sufficient gasoline in the tank.
WARNING
EWB02522Gasoline and gasoline vapors are extremely
flammable. To avoid fires and explosions and
to reduce the risk of injury when refueling, fol-
low these instructions. 1. Before refueling, turn off the engine and besure that no one is sitting on the vehicle. Nev-
er refuel while smoking, or while in the vicinity
1. Kickstarter lever
1
1. Fuel tank cap
1
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