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6-6
6
for long distances. The transmission is prop-
erly lubricated only when the engine is run-
ning. Inadequate lubrication may damage
the transmission.
●Always use the clutch when changing gears.
The engine, transmission and drive train are
not designed to withstand the shock of
forced shifting and can be damaged by shift-
ing without using the clutch.EBU20672Engine break-in TIP●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 320 km (200 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 320 km (200 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.
0–160 km (0–100 mi) or 0–10 hours
Avoid prolonged operation above 1/2 throttle. Vary
the speed of the ATV regularly. Do not operate it at
one set throttle position.
160–320 km (100–200 mi) or 10–20 hours
Avoid prolonged operation above 3/4 throttle. Rev
the engine through the gears freely, but do not use
full throttle at any time.
320 km (200 mi) or 20 hours and beyond
The ATV can now be operated normally.
NOTICEECB00220If any engine trouble should occur during the
engine break-in period, immediately have a
Yamaha dealer check the ATV.
U1BS63E0.book Page 6 Tuesday, March 13, 2012 11:43 AM
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![YAMAHA YFM350R 2013 Owners Manual 7-8
7WARNING! Operating this ATV with improper
modifications may cause changes in handling
which in some situations could lead to an acci-
dent.
[EWB01491]
Exhaust system
WARNING
EWB01501●Dry grass YAMAHA YFM350R 2013 Owners Manual 7-8
7WARNING! Operating this ATV with improper
modifications may cause changes in handling
which in some situations could lead to an acci-
dent.
[EWB01491]
Exhaust system
WARNING
EWB01501●Dry grass](/manual-img/51/53698/w960_53698-65.png)
7-8
7WARNING! Operating this ATV with improper
modifications may cause changes in handling
which in some situations could lead to an acci-
dent.
[EWB01491]
Exhaust system
WARNING
EWB01501●Dry grass or brush or other combustible ma-
terial accumulated around the engine area
could catch fire. Do not operate, idle, or park
the ATV in dry grass or other dry ground cov-
er. Keep the engine area free of dry grass,
brush, or other combustible material.●Someone touching the exhaust system dur-
ing or after operation could be burned. Do
not touch the hot exhaust system. Do not
park the ATV in a place where others might
be likely to touch it.The muffler and other engine parts become ex-
tremely hot during operation and remain hot after
the engine has stopped. To reduce the risk of fire
during operation or after leaving the ATV, do not let
brush, grass and other materials collect under the
vehicle, near the muffler or exhaust pipe, or next to
other hot parts. Check under the vehicle after op- erating in areas where combustible materials may
have collected. Do not idle or park the vehicle in
long dry grass or other dry ground cover.
To prevent burns, avoid touching the exhaust sys-
tem. Park the ATV in a place where pedestrians or
children are not likely to touch it.U1BS63E0.book Page 8 Tuesday, March 13, 2012 11:43 AM
Page 84 of 140

8-3
8
EBU21743Periodic maintenance chart for the emission control system TIP●For ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals.●For ATVs equipped with an odometer or an hour meter, follow the km (mi) or hours maintenance inter-
vals. However, keep in mind that if the ATV isn’t used for a long period of time, the month maintenance
intervals should be followed.●Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools,
data and technical skills.NO.ITEM CHECK OR MAINTENANCE
JOB INITIAL
EVERY
Whichev- er comes first month136612
km
(mi) 320
(200) 1300
(800) 2500
(1600) 2500
(1600) 5000
(3200)
hours 20 80 160 160 320
1 *Fuel line Check fuel hoses for cracks or other damage, and
replace if necessary. √√√
2 Spark plug Check condition and clean, regap, or replace if
necessary. √√√√√
3 *Valves Check valve clearance and adjust if necessary. √ √√√
4 *Carburetor Check starter (choke) operation and correct if nec-
essary.
Check engine idling speed and adjust if neces- sary. √√√√
5 *Crankcase breather
system Check breather hose for cracks or other damage,
and replace if necessary. √√√
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8-7
8
14*Chassis fasteners Make sure that all nuts, bolts, and screws are
properly tightened. √√√√√
15 *Shock absorber as-
semblies Check operation and correct if necessary.
Check for oil leakage and replace if necessary.
√√√
16 *Rear suspension re-
lay arm and con-
necting arm
pivoting points Check operation and correct if necessary.
Lubricate with lithium-soap-based grease.
√√√√
17 *Steering shaft Lubricate with lithium-soap-based grease. √√√
18 *Steering system Check operation and repair or replace if damaged.
Check toe-in and adjust if necessary.
√√√√√
19 Engine oil Change.
Check ATV for oil leakage, and correct if neces-
sary. √ √√√
20 Engine oil filter ele-
ment Clean or replace if necessary.
√√√
21 Engine oil strainer Clean. √√√
22 *Moving parts and
cables Lubricate.
√√√√
NO. ITEM
CHECK OR MAINTENANCE
JOB INITIAL EVERY
Whichev- er comes first month136612
km
(mi) 320
(200) 1300
(800) 2500
(1600) 2500
(1600) 5000
(3200)
hours 20 80 160 160 320U1BS63E0.book Page 7 Tuesday, March 13, 2012 11:43 AM
Page 90 of 140
8-9
8
EBU23213Checking the spark plug The spark plug is an important engine component,
which is easy to check. Since heat and deposits
will cause any spark plug to slowly erode, the spark
plug should be removed and checked in accor-
dance with the periodic maintenance and lubrica-
tion chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
To remove the spark plug1. Remove the spark plug cap. 2. Remove the spark plug as shown, with the
spark plug wrench included in the owner’s tool
kit.
To check the spark plug 1. Check that the porcelain insulator around the center electrode of the spark plug is a medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).1. Spark plug cap
1. Spark plug wrench
U1BS63E0.book Page 9 Tuesday, March 13, 2012 11:43 AM
Page 91 of 140
8-10
8
TIPIf the spark plug shows a distinctly different color,
the engine could be operating improperly. Do not
attempt to diagnose such problems yourself. In-
stead, have a Yamaha dealer check the ATV.2. Check the spark plug for electrode erosionand excessive carbon or other deposits, and
replace it if necessary.
3. Measure the spark plug gap with a wire thick- ness gauge and, if necessary, adjust the gap
to specification.
To install the spark plug1. Clean the surface of the spark plug gasket and its mating surface, and then wipe off any
grime from the spark plug threads.
2. Install the spark plug with the spark plug wrench, and then tighten it to the specified
torque.
Specified spark plug:
NGK/DR8EA
1. Spark plug gapSpark plug gap:0.6–0.7 mm (0.024–0.028 in)
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8-11
8
TIPIf a torque wrench is not available when installing
the spark plug, a good estimate of the correct
torque is 1/4–1/2 turn past finger tight. However,
the spark plug should be tightened to the specified
torque as soon as possible.3. Install the spark plug cap.EBU2327GEngine oil and oil filter element The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter element cleaned at the intervals speci-
fied in the periodic maintenance and lubrication
chart.
To check the engine oil level1. Place the ATV on a level surface.
2. Check the engine oil level on a cold engine.
TIPIf the engine was started before checking the oil
level, be sure to warm up the engine sufficiently,
and then wait at least ten minutes until the oil set-
tles for an accurate reading.3. Remove the engine oil filler cap, and then wipe the engine oil dipstick off with a clean
rag.
4. Insert the dipstick into the filler hole (without screwing it in), and then remove it again to
check the oil level.TIPThe engine oil should be between the minimum
and maximum level marks.
Tightening torque:Spark plug:18 Nm (1.8 m·kgf, 13 ft·lbf)
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8-15
8
NOTICEECB00300●In order to prevent clutch slippage (since the
engine oil also lubricates the clutch), do not
mix any chemical additives. Do not use oils
with a diesel specification of “CD” or oils of
a higher quality than specified. In addition,
do not use oils labeled “ENERGY CONSERV-
ING II” or higher.●Make sure that no foreign material enters the
crankcase.13. Start the engine, and then let it idle for severalminutes while checking it for oil leakage. If oil
is leaking, immediately turn the engine off and
check for the cause.
14. Turn the engine off, wait at least ten minutes, and then check the oil level and correct it if
necessary.EBU23744Cleaning the air filter element The air filter element should be cleaned at the in-
tervals specified in the periodic maintenance and
lubrication chart. Clean or, if necessary, replace
the air filter element more frequently if you are
riding in unusually wet or dusty areas.
TIPThere is a check hose at the bottom of the air filter
case. If dust or water collects in this hose, empty
the hose and clean the air filter element and air fil-
ter case.1. Place the ATV on a level surface.
2. Remove the seat. (See page 4-12.)
3. Remove the air filter case cover by unhookingthe holders.1. Air filter case check hose
U1BS63E0.book Page 15 Tuesday, March 13, 2012 11:43 AM