2019 YAMAHA YFZ450 maintenance

8-4
8
5*Exhaust system • Check for leakage and replace gasket(s) if neces-
sary.
• Check for looseness and tighten all screw clamps and joints if necessary. √√√
6Spark arrester • Clean. √√√
7 *Air induction sys-
tem • Check the air cut-off valve, reed valve, and hose
for damage.
• Replace any damaged parts if necessary. √√√√√
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
UBW262E0.book Page 4 Tuesday, April 3, 2018 10:59 AM

8-5
8
EBU2186EPeriodic maintenance chart: General maintenance and lubricationTIPFor ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals in-
stead.
 For odometer or hour meter-equipped vehicles, follow the month maintenance interval if the ATV isn’t
ridden for the stated mileage or engine operating hours.
 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 Air filter element • Clean and replace if necessary. Every 20–40 hours (more often in wet or
dusty areas)
2 *Clutch • Check operation and adjust if necessary. √ √√√
3 *Front brake • Check operation and correct if necessary.
• Check fluid level and ATV for fluid leakage, and
correct if necessary. √√√√√
• Replace brake pads. Whenever worn to the limit
4 *Rear brake • Check operation and correct if necessary.
• Check fluid level and ATV for fluid leakage, and
correct if necessary. √√√√√
• Replace brake pads. Whenever worn to the limit
UBW262E0.book Page 5 Tuesday, April 3, 2018 10:59 AM

8-6
8
5*Brake hoses • Check for cracks or other damage, and replace if
necessary. √√√√
• Replace. Every 4 years
6 *Brake fluid • Change. Every 2 years
7 *Parking brake • Check operation and adjust if necessary. √√√√√
8 *Wheels • Check runout and for damage, and replace if nec-
essary. √ √√√
9 *Tires • Check tread depth and for damage, and replace if
necessary.
• Check air pressure and balance, and correct if necessary. √ √√√
10 *Wheel hub bearings • Check for looseness or damage, and replace if
necessary. √ √√√
11 *Swingarm pivots • Check operation and for excessive play, and re-
place bearings if necessary.
• Lubricate with lithium-soap-based grease. √√√
12 *Upper and lower
arm pivots • Lubricate with lithium-soap-based grease.
√√√
13 Drive chain • Check chain slack and adjust if necessary.
• Check rear wheel alignment and correct if neces-
sary.
• Clean and 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 80 160 160 320
UBW262E0.book Page 6 Tuesday, April 3, 2018 10:59 AM

8-7
8
14*Drive chain roller • Check for wear and replace if necessary. √√√
15 *Chassis fasteners • Make sure that all nuts, bolts, and screws are
properly tightened. √√√√√
16 *Shock absorber as-
semblies • Check operation and correct if necessary.
• Check for oil leakage and replace if necessary.
√√√
17 *Rear suspension re-
lay arm and con-
necting arm
pivoting points • Check operation and correct if necessary.
√√√√
18 *Steering shaft • Lubricate with lithium-soap-based grease. √√√
19 *Steering system • Check operation and repair or replace if dam-
aged.
• Check toe-in and adjust if necessary. √√√√√
20 Engine oil • Change.
• Check ATV for oil leakage, and correct if neces-
sary. √ √√√
21 Engine oil filter ele-
ment
• Replace.
√√√
22 *Cooling system • Check coolant level and ATV for coolant leakage,
and correct if necessary. √√√√√
• Replace coolant. Every 2 years
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 320UBW262E0.book Page 7 Tuesday, April 3, 2018 10:59 AM

8-8
8
EBU29431TIPSome maintenance items need more frequent service if you are riding in unusually wet, dusty, sandy or
muddy areas, or at full-throttle.
 Replace the fuel hose every five years and if cracked or damaged.
 Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid level.
• Every two years replace the internal components of the brake master cylinders and calipers, and
change the brake fluid.23 *Moving parts and
cables •Lubricate.
√√√√
24 *Throttle lever • Check operation.
• Check throttle lever free play, and adjust if neces-
sary.
• Lubricate cable and lever housing. √√√√√
25 *Front and rear
brake switches • Check operation and correct if necessary.
√√√√√
26 *Lights and switches • Check operation and correct if necessary.
• Adjust headlight beams. √√√√√
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 320UBW262E0.book Page 8 Tuesday, April 3, 2018 10:59 AM

8-10
8
EBU30131Removing and installing the cowling
and panelsThe cowling and panels shown need to be re-
moved to perform some of the maintenance jobs
described in this chapter. Refer to this section
each time a cowling or panel needs to be removed
and installed.
EBU29596Panel A
To remove the panel1. Remove the seat. (See page 4-10.)
2. Remove the fuel tank cap by turning it coun-terclockwise. (See page 4-8.) NOTICE: Make
sure that no foreign material enters the
fuel tank.
[ECB01052]
3. Loosen the quick fasteners.
1. Panel A
2. Panel B
3. Cowling
1
2
3
1. Panel C
1
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8-13
8To install the cowling
1. Place the cowling in the original position, and
then tighten the quick fasteners.
2. Install panels C, B and A.EBU29442Checking the spark plugThe spark plug is an important engine component,
which should be checked periodically, preferably
by a Yamaha dealer. 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.
The porcelain insulator around the center elec-
trode of the spark plug should be a medium-to-
light tan (the ideal color when the vehicle is ridden
normally). If the spark plug shows a distinctly dif-
ferent color, the engine could be operating im-
properly. Do not attempt to diagnose such
problems yourself. Instead, have a Yamaha dealer
check the vehicle.
If the spark plug shows signs of electrode erosion
and excessive carbon or other deposits, it should
be replaced.
1. Quick fastener
1. Quick fastener
1
1
1
1
UBW262E0.book Page 13 Tuesday, April 3, 2018 10:59 AM

8-14
8
Before installing the spark plug, the spark plug
gap should be measured with a wire thickness
gauge and, if necessary, adjusted to specification.
Clean the surface of the spark plug gasket and its
mating surface, and then wipe off any grime from
the spark plug threads.
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 speci-
fied torque as soon as possible. EBU2949DEngine oil and oil filter elementThe engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter element replaced at the intervals spec-
ified in the periodic maintenance and lubrication
chart.
To check the engine oil level
1. Park the ATV on a level surface.
2. Start the engine, warm it up until the engine oil has reached a normal temperature of 60
°C (140 °F), let it continue to idle for ten sec-
onds or more, and then turn the engine off.
Specified spark plug:
NGK/CR8E
1. Spark plug gapSpark plug gap:0.7–0.8 mm (0.028–0.031 in)
Tightening torque:Spark plug:13 N·m (1.3 kgf·m, 9.6 lb·ft)
UBW262E0.book Page 14 Tuesday, April 3, 2018 10:59 AM