2016 YAMAHA WR 450F transmission

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

ENGINE SPECIFICATIONS
2-5
CrankshaftCrank assembly width 61.93–62.00 mm (2.438–2.441 in)
Runout limit 0.030 mm (0.0012 in)
Big end side clearance 0.150–0.450 mm (0.0059–0.0177 in)
BalancerBalancer drive method Gear
ClutchClutch type Wet, multiple-disc
Clutch release method Inner push, cam push
Clutch lever free play 7.0–12.0 mm (0.28–0.47 in)
Friction plate 1 thickness 2.92–3.08 mm (0.115–0.121 in)
Wear limit 2.85 mm (0.112 in)
Plate quantity 3 pcs
Friction plate 2 thickness 2.92–3.08 mm (0.115–0.121 in)
Wear limit 2.85 mm (0.112 in)
Plate quantity 5 pcs
Clutch plate 1 thickness 1.90–2.10 mm (0.075–0.083 in)
Plate quantity 4 pcs
Warpage limit 0.10 mm (0.004 in)
Clutch plate 2 thickness 1.50–1.70 mm (0.059–0.067 in)
Plate quantity 3 pcs
Warpage limit 0.10 mm (0.004 in)
Clutch spring free length 50.00 mm (1.97 in)
Limit 47.50 mm (1.87 in)
Spring quantity 6 pcs
Push rod bending limit 0.10 mm (0.004 in)
TransmissionTransmission type Constant mesh 5-speed
Primary reduction system Spur gear
Primary reduction ratio 2.609 (60/23)
Final drive Chain
Secondary reduction ratio 3.846 (50/13)
Operation Left foot operation
Gear ratio
1st 2.417 (29/12)
2nd 1.733 (26/15)
3rd 1.313 (21/16)
4th 1.050 (21/20)
5th 0.840 (21/25)
Main axle runout limit 0.08 mm (0.0032 in)
Drive axle runout limit 0.08 mm (0.0032 in)
Shifting mechanism
Shift mechanism type Shift drum and guide bar
Shift fork guide bar bending limit 0.050 mm (0.0020 in)
Shift fork thickness 4.85 mm (0.1909 in)
Decompression deviceDevice type Auto decomp
Air filterAir filter element Wet element
Air filter oil grade Yamaha foam air filter oil or other quality foam air filter oil

LUBRICATION POINTS AND LUBRICANT TYPES
2-21
EAS2GC1068
LUBRICATION POINTS AND LUBRICANT TYPES
EAS2GC1069ENGINE
Lubrication point Lubricant types
Oil seal lips
Bearing
O-ring
Camshaft cap bolt threads and contacting surface
Cylinder head bolt threads, seats, washers
Valve stems
Valve stem ends
Valve lifter outer surface
Camshaft lobe and journal
Valve lifter top surface
Crankshaft journal
Crankshaft big end thrust surfaces
Piston outer surface
Piston pin outer surface
Decompression system moving parts
Water pump impeller shaft
Oil pump rotors (inner and outer)
Oil passage gasket
Oil pump shaft
Kick gear and ratchet wheel
Kick shaft
Kick idle gear inner surface
Ratchet wheel and ratchet wheel guide contacting portion
Primary drive gear nut threads and contacting surface
Primary driven gear inner surface and end surface
Clutch push rod washer
Clutch push rod 1 outer surface
Clutch push rod 1 thrust surface
Clutch push rod 2 outer surface
Push lever shaft outer surface
Transmission gear inner surface (wheel and pinion) and collar
Transmission gears (shift fork groove)
Shift cam grooves
Shift fork and shift fork guide outer surface
Shift shaft and collar
Shift lever assembly moving parts
Damper assembly shaft, thrust surfaces, washers
LS
E
LS
E
M
M
M
E
M
E
M
E
E
M
E
E
E
LS
E
M
E
E
M
E
E
E
E
E
E
E
M
E
E
E
E
E
E

PERIODIC MAINTENANCE
3-5
PISTON PINInspect
Replace
CYLINDER HEAD Inspect carbon deposits and
eliminate them.
Inspect and clean
Change gasket.
CYLINDER
Inspect and clean Inspect score marks.
Inspect wear.
Replace
CLUTCH Inspect and adjust Inspect housing, friction plate,
clutch plate and spring.
Replace
TRANSMISSION Inspect
Replace bearing
SHIFT FORK, SHIFT
CAM, GUIDE BAR Inspect Inspect wear.
ROTOR NUT
Retighten
MUFFLER Inspect and re-
tighten
Clean
Replace
CRANK
Inspect and clean
THROTTLE BODY Inspect
SPARK PLUG Inspect and clean
Replace
DRIVE CHAIN Use chain lube.
Lubricate, slack,
alignment Chain slack: 50.0–60.0 mm
(1.97–2.36 in)
Replace ITEM
After
break- in Every
race Every
third (or
500
km) Every
fifth (or
1,000 km) As re-
quired Remarks

CHASSIS
3-31
• When refilling, be careful that water does not enter the brake fluid reservoir. Water
will significantly lower the boiling point of
the brake fluid and could cause vapor
lock.
ECA
NOTICE
Brake fluid may damage painted surfaces
and plastic parts. Therefore, always clean
up any spilt brake fluid immediately.
EAS2GC1110ADJUSTING THE DRIVE CHAIN SLACKECA
NOTICE
A drive chain that is too tight will overload
the engine and other vital parts, and one
that is too loose can skip and damage the
swingarm or cause an accident. Therefore,
keep the drive chain slack within the speci-
fied limits.
1. Use a suitable stand to raise the rear wheel off the ground.
EWA
WARNING
Securely support the vehicle so that there is
no danger of it falling over.
2. Shift the transmission into the neutral posi-
tion.
3. Pull the drive chain up above the drive chain guide installation bolt with a force of about
50 N (5.0 kgf, 36 lbf).
4. Check: • Drive chain slack “a”
Out of specification  Regulate.
TIP
Measure drive chain slack between the drive
chain guide and the bottom of the chain as
shown. 5. Adjust:
• Drive chain slack
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a. Loosen the wheel axle nut “1”.
b. Loosen both locknuts “2”.
c. Turn the adjusting bolt “3” in direction “a” or “b” until the specified drive chain slack is ob-
tained.
TIP
• To maintain the proper wheel alignment, ad-just both sides evenly.
• Push the rear wheel forward to make sure that
there is no clearance between the swingarm
end plates and the ends of the swingarm.
d. Tighten the locknut.
e. Tighten the wheel axle nut.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EAS2GC1111CHECKING THE FRONT FORK LEGS
1. Stand the vehicle upright on a level surface.
EWA
WARNING
Securely support the vehicle so that there is
no danger of it falling over.
2. Check: • Inner tubeDamage/scratches  Replace.
• Front fork leg (s) Oil leaks between inner tube and outer tube
 Replace the oil seal.
Drive chain slack (on a suitable
stand)
50.0–60.0 mm (1.97–2.36 in)
a
Direction “a”The drive chain slack decreases.
Direction “b” The drive chain slack increases.
Locknut21 Nm (2.1 m·kgf, 15 ft·lbf)
Wheel axle nut 125 Nm (12.5 m·kgf, 90 ft·lbf)
1
32
a
b
T R..
T R..

GENERATOR AND STARTER CLUTCH....................................................... 6-63
REMOVING THE GENERATOR .............................................................. 6-65
CHECKING THE STARTER CLUTCH ..................................................... 6-65
INSTALLING THE STARTER CLUTCH ................................................... 6-66
INSTALLING THE GENERATOR............................................................. 6-67
CRANKCASE ................................................................................................. 6-69
DISASSEMBLING THE CRANKC ASE..................................................... 6-72
REMOVING THE CRANKCASE BEARING ............................................. 6-72
CHECKING THE TIMING CHAIN, TIMING CHAIN GUIDE, OIL
STRAINER .............................................................................................. 6-72
CHECKING THE CRANKCASE ............................................................... 6-72
INSTALLING THE OIL SEAL ................................................................... 6-73
ASSEMBLING THE CRANKCASE........................................................... 6-73
CRANKSHAFT ASSEMBLY AND BALANCER SHAFT ............................... 6-74
REMOVING THE BALANCER SHAFT..................................................... 6-75
REMOVING THE CRANKSHAFT ASSEMBLY ........................................ 6-75
CHECKING THE CRANKSHA FT ASSEMBLY......................................... 6-75
INSTALLING THE CRANKSHA FT ASSEMBLY....................................... 6-76
TRANSMISSION ............................................................................................. 6-77
REMOVING THE TRANSMISSION ......................................................... 6-78
CHECKING THE SHIFT FORKS.............................................................. 6-78
CHECKING THE SHIFT DRUM ASSEMBLY ........................................... 6-79
CHECKING THE TRANSMISSION .......................................................... 6-79
INSTALLING THE TRANSMISSION ........................................................ 6-79

CRANKCASE
6-71
Removing the bearing and oil seal
OrderPart name Q’tyRemarks
Transmission Refer to “TRANSMISSION” on page 6-77.
Shift cam and shift fork Refer to “TRANSMISSION” on page 6-77.
1 Circlip 1
2Oil seals 3
3 Bearing 11
For installation, reverse the removal proce-
dure.
LT
LT
LT
LT
LT
12 2
3
3
33
3
3
3
3
3 3
New
NewLT

CRANKCASE
6-72
EAS2GC1311DISASSEMBLING THE CRANKCASE
1. Separate:• Right crankcase
• Left crankcase
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the crankcase bolts.
TIP
Loosen each bolt 1/4 of a turn at a time and af-
ter all the bolts are loosened, remove them.
b. Remove the right crankcase “1”.
TIP
• Place the crankcase with its left side down-ward and split it by inserting a screwdriver tip
into the splitting slit “a” in the crankcase.
• Lift the right crankcase horizontally while light-
ly patting the crankcase splitting slit and the
engine mounting boss using a soft hammer,
and leave the crankshaft and the transmission
with the left crankcase.
ECA33DD041
NOTICE
Use soft hammer to tap on the case half.
Tap only on reinforced portions of case. Do
not tap on gasket mating surface. Work
slowly and carefully. Make sure the case
halves separate evenly. If the cases do not
separate, check for a remaining case bolt or
fitting. Do not force. c. Remove the dowel pins and O-ring.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EAS2GC1312REMOVING THE CRANKCASE BEARING
1. Remove:
• Bearing “1”
TIP
• Remove the bearing from the crankcase by pressing its inner race.
• Do not use the removed bearing.
EAS2GC1313CHECKING THE TIMING CHAIN, TIMING
CHAIN GUIDE, OIL STRAINER
1. Check:• Timing chainStiffness  Replace the camshaft sprocket,
timing chain and crankshaft sprocket as a
set.
2. Check: • Timing chain guide
Damage/wear  Replace
EAS2GC1314CHECKING THE CRANKCASE
1. Wash:
• Crankcase
TIP
• Wash the crankcase in a mild solvent.
• Remove any remaining gasket from the
crankcase mating surface.
2. Check: • CrankcaseCrack/damage  Replace.
1
a