2016 YAMAHA WR 450F check engine

STARTING AND BREAK-IN
1-28
EAS2GC1048
STARTING AND BREAK-IN
EAS2GC1049FUEL
Always use the recommended fuel as stated
below. Also, be sure to use new gasoline the
day of a race.
ECA
NOTICE
Use only unleaded gasoline. The use of
leaded gasoline will cause severe damage
to the engine internal parts such as valves,
piston rings, and exhaust system, etc.
TIP
Your Yamaha engine has been designed to use
premium unleaded gasoline with a pump oc-
tane number [(R+M)/2] of 91 or higher, or a re-
search octane number of 95 or higher. If
knocking (or pinging) occurs, use a gasoline of
a different brand.
EWA
WARNING
• For refueling, be sure to stop the engine and use enough care not to spill any fuel.
Also be sure to avoid refueling close to a
fire.
• Refuel after the engine, exhaust pipe, etc.
have cooled off.
Gasohol (For USA and Canada)
There are two types of gasohol: gasohol con-
taining ethanol and that containing methanol.
Gasohol containing ethanol can be used if the
ethanol content does not exceed 10%. Gasohol
containing methanol is not recommended by
Yamaha because it can cause damage to the
fuel system or vehicle performance problems.
EAS2GC1050HANDLING NOTEEWA
WARNING
Never start or run the engine in a closed ar-
ea. The exhaust fumes are poisonous; they
can cause loss of consciousness and death
in a very short time. Always operate the ma-
chine in a well-ventilated area.
ECA
NOTICE
• Unlike a two-stroke engine, this engine cannot be kick started when the throttle is
open because the kickstarter may kick
back. Also, if the throttle is open the air/
fuel mixture may be too lean for the engine
to start.
• Before starting the machine, perform the
checks in the pre-operation check list.
EAS2GC1051AIR FILTER MAINTENANCE
According to “CLEANING THE AIR FILTER
ELEMENT” section in the CHAPTER 3, apply
the Yamaha foam air filter oil or other quality
foam air filter oil to the element. (Excess oil in
the element may adversely affect engine start-
ing.)
EAS2GC1052STARTING A COLD ENGINEECA
NOTICE
For maximum engine life, never accelerate
hard when the engine is cold!
In order for the ignition circuit cut-off system to
enable starting, one of the following conditions
must be met:
• The transmission is in the neutral position.
• The transmission is in gear with the clutch le- ver pulled.
1. Pull the starter knob/idle screw “1” to its full length.
TIP
When the ambient temperature is 15°C (59°F)
or below, use the starter knob/idle screw.
2. Completely close the throttle.
3. Start the engine by pushing the start switch.If the engine fails to start when using the
start switch, release it, wait a few seconds,
and then try again.
Each starting attempt should be as short as
possible to preserve the battery. Do not
crank the engine more than 10 seconds on
any one attempt. If the engine does not start
with the starter motor, try using the kickstart-
er.
Recommended fuel
Premium unleaded gasoline
only
Fuel tank capacity 7.5 L (2.0 US gal, 1.7 lmp.gal)
Fuel reserve amount 2.0 L (0.5 US gal, 0.4 Imp.gal)
1

STARTING AND BREAK-IN
1-30
EAS2GC1053STARTING A WARM ENGINE
Follow the same procedure as for starting a
cold engine with the exception that the starter is
not required when the engine is warm.
TIP
If it fails to start, fully open the throttle grip and
give 10 to 20 slow kicks to clear the engine of
the rich air-fuel mixture retained in it.
EAS2GC1054BREAK-IN PROCEDURES
A break-in is important so that rotating portion,
sliding surfaces, and mounted areas may fit
one another, and that the rider may become ac-
customed to the machine.
ECA
NOTICE
Before running, do maintenance on the air
filter element.
Refer to “CLEANING THE AIR FILTER ELE-
MENT” on page 3-14.
1. After warming up the engine, drive it for about 20 minutes at a throttle opening of 1/2
or less.
TIP
This model is equipped with an engine auto-
stop system. The engine stops automatically if
left idling for 7 minutes. If the engine stops,
push the start switch or push down the kick-
starter lever to restart the engine.
2. Make a pit stop, and check mounted areas
for looseness, oil leaks, or other problems.
3. Then, drive it for about 40 minutes at a throt- tle opening of 3/4 or less.
4. Make a pit stop again, and thoroughly check mounted areas for looseness, oil leaks, or
other problems. Thorough checks and ad-
justments are required in particular for
stretch of cables, free play of the brake,
stretch of the drive chain, looseness of the
spoke, and so on.
ECA
NOTICE
After a break-in or after each race, always
check the points shown in “TORQUE-
CHECK POINTS” for tightening torques and
retighten them. (Refer to “TORQUE-CHECK
POINTS” on page 1-32.)
Also when the following parts are replaced,
a break-in is required.
• Cylinder and Crankshaft: A break-in is re-quired for about an hour.
• Piston, Piston ring, Valve, Camshaft, and
Gear: A break-in is required for about 30
minutes at a throttle opening of 1/2 or less.
Observe the condition of the engine careful-
ly during a break-in.
For checkpoints for a break-in, see “MAIN-
TENANCE AFTER BREAK-IN”. If any prob-
lem is found, immediately stop the engine
and make a checkup.

MAINTENANCE AFTER BREAK-IN
1-31
EAS2GC1055
MAINTENANCE AFTER BREAK-IN
After a break-in, perform careful maintenance
to get ready for the next practice or race.
Refer to “PRE-OPERATION INSPECTION
AND MAINTENANCE” on page 3-9.
EAS2GC1056MAJOR MAINTENANCE
1. For the engine• Leaks around the engineCheck for pressure l eaks from the cylinder
head or the cylinder, oil leaks from the
crankcase or the case cover, leaks from the
coolant system, and other leaks.
• Check that the valve, the cylinder head, the cylinder, the piston, and the piston ring fit
one another, and that contact between the
valve and the cylinder head, and that be-
tween the cylinder and the piston are cor-
rect.
• Engine oil change Drain the oil, and check for dirt and foreign
materials such as metal chips. (If any foreign
material is mixed, disassemble and check
the crankcase.)
Pour the specified amount of the recom-
mended oil.
• AC magneto
Check for looseness in mounted areas of
the rotor and the stator.
Check that the connector is not being dis-
connected.
• Silencer Check the main body and stay for cracks.
Check for leaks.
• Mounting bolts and nuts Check for looseness in mounted areas of
parts, as well as engine mounting bolts and
engine brackets.
2. For the chassis
• Check welds and mounted areas of the frame, the swingarm, the link, the bracket,
and so on, for looseness and cracks.
• Wheel (s) Check the wheel for runout. Check the
spoke for looseness.
• Brake(s) Check the brake disc mounting bolt for
looseness.
Check that the reservoir contains the speci-
fied amount of brake fluid. Check for leaks. • Cable
Grease and adjust cables.
•Drive chain
Lubricate the drive chain and adjust its ten-
sion.
• Fuel tank
Clean the inside of the fuel tank. Check for
leaks.
• Suspension
Check for oil leaks in the front fork or the rear
shock absorber. Check that the mounted
conditions are good.
• Sprocket Check for looseness in the sprocket mount-
ed on the rear wheel.
• Mounting bolts and nuts
Check mounted areas for looseness.
ECA
NOTICE
After a break-in or before each race, always
check the points shown in “TORQUE-
CHECK POINTS” for tightening torques and
retighten them. (Refer to “TORQUE-CHECK
POINTS” on page 1-32.)
• Greasing and oilingAlways grease or oil the specified points.

TORQUE-CHECK POINTS
1-32
EAS2GC1057
TORQUE-CHECK POINTS
Frame constructionFrame to rear frame
Frame to engine protector
Combined seat and fuel tank Fuel tank to frame
Engine mounting Frame to engine
Engine bracket to engine
Engine bracket to frame
Seat Seat to frame
Steering Steering stem to handlebar Steering stem to frame
Steering stem to upper bracket
Upper bracket to handlebar
Suspension Front Steering stem to front fork Front fork to upper bracket
Front fork to lower bracket
Rear Link Assembly of links
Link to frame
Link to rear shock absorber
Link to swingarm
Mounting of rear shock absorber Rear shock absorber and frame
Mounting of swingarm Tightening of pivot shaft
Wheel (s) Mounting of wheel Front Tightening of wheel axle
Tightening of axle holder
Tightening of spoke nipple
Rear Tightening of wheel axle Wheel to rear wheel sprocket
Tightening of spoke nipple
Brake(s) Front Brake caliper to front fork
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to handle-
bar
Tightening of bleed screw
Tightening of brake hose holder
Rear Brake pedal to frame Brake disc to wheel
Tightening of union bolt
Brake master cylinder to frame
Tightening of bleed screw
Tightening of brake hose holder
Shift pedal Shift pedal to shift shaft

MOTORCYCLE CARE AND STORAGE
1-36
e. Remove the spark plug cap from the spark plug, and then install the spark plug and the
spark plug cap. WARNING! To prevent
damage or injury from sparking, make
sure to ground the spark plug electrodes
while turning the engine over.
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4. Lubricate all control cables and the pivoting points of all levers and pedals as well as of
the sidestand/ centerstand.
5. Check and, if necessary, correct the tire air
pressure, and then lift the motorcycle so that
both of its wheels are off the ground. Alter-
natively, turn the wheels a little every month
in order to prevent the tires from becoming
degraded in one spot.
6. Cover the muffler outlet with a plastic bag to
prevent moisture from entering it.
7. Remove the battery and fully charge it. Store it in a cool, dry place and charge it once a
month. Do not store the battery in an exces-
sively cold or warm place [less than 0 °C (30
°F) or more than 30 °C (90 °F)]. For more in-
formation on storing the battery, See page
9-69.
TIP
Make any necessary repairs before storing the
motorcycle.

TIGHTENING TORQUES
2-13
EAS2GC1066ENGINE TIGHTENING TORQUES
TIP
- marked portion shall be checked for torque tightening after break-in or before each race.
ITEM Thread
size Q’ty TIGHTENING TORQUES Remarks
Camshaft cap bolt M6 8 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Cylinder head blind plug M12 1 28 Nm (2.8 m·kgf, 20 ft·lbf)
Spark plug M10 1 13 Nm (1.3 m·kgf, 9.4 ft·lbf)
Cylinder head stud bolt (exhaust
pipe) M6 3 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Cylinder head bolt M10 4See TIP.*1
Cylinder head bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Cylinder head cover bolt M6 3 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil passage plug (cylinder head) M8 1 15 Nm (1.5 m·kgf, 11 ft·lbf)
Cylinder bolt M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil pressure check bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Balancer weight plate screw M6 3 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Balancer driven gear nut M14 1 50 Nm (5.0 m·kgf, 36 ft·lbf) Use a
lock
washer.
Balancer nut M10 1 45 Nm (4.5 m·kgf, 33 ft·lbf) Use a
lock
washer.
Timing chain guide stopper plate
(exhaust side) M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Timing chain tensioner cap bolt M6 1 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Timing chain tensioner bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Coolant drain bolt M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Radiator hose clamp screw M6 8 1.5 Nm (0.15 m·kgf, 1.1 ft·lbf)
Radiator bolt M6 4 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Radiator pipe bolt M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Radiator pipe joint bolt M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Radiator fan bolt M6 3 8 Nm (0.8 m·kgf, 5.8 ft·lbf)
Water pump housing cover bolt M6 4 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil pump bolt M5 2 5 Nm (0.5 m·kgf, 3.6 ft·lbf)
Oil pump cover screw M4 1 2.0 Nm (0.20 m·kgf, 1.4 ft·lbf)
Oil strainer bolt M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil passage cover bolt (left crank-
case cover) M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Throttle cable cover bolt M5 1 3.5 Nm (0.35 m·kgf, 2.5 ft·lbf)
Throttle body joint bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
E
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TIGHTENING TORQUES
2-14
Throttle body joint clamp boltM5 1 3.0 Nm (0.30 m·kgf, 2.2 ft·lbf)
Air filter joint clamp bolt M4 1 3.5 Nm (0.35 m·kgf, 2.5 ft·lbf)
Air filter case bolt M6 3 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Air filter bolt M6 1 2.0 Nm (0.20 m·kgf, 1.4 ft·lbf)
Air filter guide holder screw M5 8 2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
Air filter case cap screw M5 1 2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
Starter knob/Idle screw M12 1 2.1 Nm (0.21 m·kgf, 1.5 ft·lbf)
Throttle cable nut (pull) M10 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Throttle cable nut (return) M10 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Clutch cable adjuster and locknut M6 1 4.0 Nm (0.40 m·kgf, 2.9 ft·lbf)
Clutch cable locknut (engine side) M8 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Exhaust pipe nut M6 3See TIP.*2
Exhaust pipe protector screw M6 4 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Exhaust pipe bracket bolt M8 1 20 Nm (2.0 m·kgf, 14 ft·lbf)
Frame and silencer bolt (front) M8 1 30 Nm (3.0 m·kgf, 22 ft·lbf)
Frame and silencer bolt (rear) M8 1 30 Nm (3.0 m·kgf, 22 ft·lbf)
Exhaust pipe clamp bolt M8 2 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Spark arrester bolt M5 4 9 Nm (0.9 m·kgf, 6.5 ft·lbf)
Muffler cap bolt M5 6 5 Nm (0.5 m·kgf, 3.6 ft·lbf)
Oil nozzle bolt M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Engine oil drain bolt M10 1 20 Nm (2.0 m·kgf, 14 ft·lbf)
Crankcase bolt M6 12 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Clutch cable holder bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Crankshaft end accessing screw M36 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Timing mark accessing screw M14 1 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Drive chain sprocket cover bolt M6 2 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Crankcase bearing cover plate
screw M6 8 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Crankcase bearing cover plate
screw (crankshaft) M8 4 18 Nm (1.8 m·kgf, 13 ft·lbf) Crimp.
Clutch cover bolt M6 7 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Left crankcase cover bolt M6 7 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Right crankcase cover bolt M6 11 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil filter element cover bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil level check window bolt M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Kick shaft ratchet wheel guide bolt M6 2 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Kickstarter lever bolt M8 1 33 Nm (3.3 m·kgf, 24 ft·lbf)
ITEM
Thread
size Q’ty TIGHTENING TORQUES Remarks
LT
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TIGHTENING TORQUES
2-17
EAS2GC1067CHASSIS TIGHTENING TORQUES
TIP
- marked portion shall be checked for torque tightening after break-in or before each race.
ITEM Thread
size Q’ty TIGHTENING TORQUES Remarks
Outer tube and upper bracket bolt M8 4 21 Nm (2.1 m·kgf, 15 ft·lbf)
Outer tube and lower bracket bolt M8 4 21 Nm (2.1 m·kgf, 15 ft·lbf)
Upper bracket and steering stem nut M24 1 145 Nm (14.5 m·kgf, 105 ft·lbf)
Upper handlebar holder bolt M8 4 28 Nm (2.8 m·kgf, 20 ft·lbf)
Lower handlebar holder nut M10 2 40 Nm (4.0 m·kgf, 29 ft·lbf)
Engine stop switch screw M3 1 0.5 Nm (0.05 m·kgf, 0.36 ft·lbf)
Start switch screw M4 1 0.5 Nm (0.05 m·kgf, 0.36 ft·lbf)
Lower ring nut M28 1See TIP.
Outer tube and damper assembly M51 2 30 Nm (3.0 m·kgf, 22 ft·lbf)
Inner tube and adjuster M22 2 55 Nm (5.5 m·kgf, 40 ft·lbf)
Damper assembly and base valve M42 2 28 Nm (2.8 m·kgf, 20 ft·lbf)
Damper assembly adjuster M12 2 29 Nm (2.9 m·kgf, 21 ft·lbf)
Bleed screw (front fork) and base
valve M5 2 1.3 Nm (0.13 m·kgf, 0.94 ft·lbf)
Front fork protector bolt M6 6 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Front fork protector and brake hose
holder nut M6 2 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Throttle grip cap screw M5 2 3.8 Nm (0.38 m·kgf, 2.8 ft·lbf)
Clutch lever holder bolt M6 2 3.8 Nm (0.38 m·kgf, 2.8 ft·lbf)
Clutch lever nut M6 1 4.0 Nm (0.40 m·kgf, 2.9 ft·lbf)
Front brake master cylinder holder
bolt M6 2 9 Nm (0.9 m·kgf, 6.5 ft·lbf)
Front brake master cylinder reser-
voir cap screw M4 2 1.5 Nm (0.15 m·kgf, 1.1 ft·lbf)
Front brake lever pivot bolt M6 1 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Front brake lever pivot nut M6 1 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Front brake lever position locknut M6 1 5 Nm (0.5 m·kgf, 3.6 ft·lbf)
Front brake hose holder and lower
bracket bolt M6 1 9 Nm (0.9 m·kgf, 6.5 ft·lbf)
Front brake hose union bolt M10 2 30 Nm (3.0 m·kgf, 22 ft·lbf)
Front brake caliper bolt M8 2 23 Nm (2.3 m·kgf, 17 ft·lbf)
Front brake pad pin M10 1 17 Nm (1.7 m·kgf, 12 ft·lbf)
Front brake pad pin plug M10 1 2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
Front brake caliper bleed screw M8 1 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Front wheel axle nut M16 1 90 Nm (9.0 m·kgf, 65 ft·lbf)
Front wheel axle pinch bolt M8 4 21 Nm (2.1 m·kgf, 15 ft·lbf)
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