light YAMAHA WR 400F 2000 User Guide

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SPECCABLE ROUTING DIAGRAM
1Throttle cable
2Lights switch
3Lights switch lead
4Clamp
5Decompression cable
6Clutch cable
7Hose guide
8Trip meter
9Brake hose
0“ENGINE STOP” button leadFasten the “ENGINE STOP” button lead to the handlebar with the
plastic band.
õPass the decompression cable between the brake hose and clutch
cable.
‚Pass the throttle cables between the handle crown and trip meter.
ëPass the light switch leads behind the “ENGINE STOP” button lead,
then pass the head light lead (of the light switch leads) in front of the
head pipe.
äInstall the trip meter cable so that its bent portion faces the chassis
rear.
ìInstall the brake hose so that it contacts the master cylinder projec-
tion and that its bent portion faces downward.

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INSP
ADJ
AIR FILTER CLEANING
CAUTION:
Never run the engine without the air filter
element in place; this would allow dirt and
dust to enter the engine and cause rapid
wear and possible engine damage.
1. Remove:
lSeat
2. Disconnect:
lTail light lead connectors 1
3. Remove:
lAir filter case cover 2
4. Remove:
lFitting bolt 1
lWasher 2
lAir filter element 3
lFilter guide 4
5. Clean:
lAir filter element
Clean them with solvent.
NOTE:
After cleaning, remove the remaining solvent
by squeezing the element.
CAUTION:
lDo not twist the element when squeezing
the element.
lLeaving too much of solvent in the ele-
ment may result in poor starting.
6. Inspect:
lAir filter element
Damage ® Replace.
7. Apply:
lFoam-air-filter oil or engine mixing oil
To the element.
NOTE:
Squeeze out the excess oil. Element should be
wet but not dripping.
8. Install:
lFilter guide 1
NOTE:
Align the projection a on filter guide with the
hole b in air filter element.

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INSP
ADJ
4. Inspect:
lOil level
Oil level should be between maximum
a and minimum b marks.
Oil level low ® Add oil to proper level.
NOTE:
When inspecting the oil level, do not screw the
oil level gauge into the oil tank.
Insert the gauge lightly.
(For USA and CDN)
CAUTION:
lDo not add any chemical additives.
Engine oil also lubricates the clutch and
additives could cause clutch slippage.
lDo not allow foreign material to enter the
crankcase.
(Except for USA and CDN)
CAUTION:
lDo not add any chemical additives or use
oils with a grade of CD a or higher.
lDo not use oils labeled “ENERGY CON-
SERVING II” b or higher. Engine oil also
lubricates the clutch and additives could
cause clutch slippage.
lDo not allow foreign materials to enter the
crankcase.
Recommended oil:
At 5 ˚C (40 ˚F) or higher
Yamalube 4 (20W-40) or SAE
20W-40 type SH motor oil
(Non-Friction modified)
At 15 ˚C (60 ˚F) or lower õ
Yamalube 4 (10W-30) or SAE
10W-30 type SH motor oil
(Non-Friction modified)
and/or
Yamalube 4-R (15W-50)
(Non-Friction modified)
Recommended oil:
Refer to the following chart for
selection of oils which are suited
to the atmospheric temperatures.
Recommended engine oil classi-
fication:
API STANDARD:
API “SH” or higher grade
(Designed primarily for motor-
cycles)-20
-4-10
140
3010
5020
6830
8640 50
104
122¡CTemp.
¡F
10W/30
10W/40
20W/40
20W/50
a
b
ENGINE OIL LEVEL INSPECTION

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INSP
ADJENGINE OIL REPLACEMENT/
PILOT SCREW ADJUSTMENT
10. Install:
lOil filler plug
11. Inspect:
lEngine (for oil leaks)
lOil level
Refer to “ENGINE OIL LEVEL INSPEC-
TION”.
12. Check:
lOil pressure
PILOT SCREW ADJUSTMENT
1. Adjust:
lPilot screw 1
* Except for USAChecking steps:
lSlightly loosen the oil gallery bolt 1.
lStart the engine and keep it idling until oil
starts to seep from the oil gallery bolt. If no
oil comes out after one minute, turn the
engine off so it will not seize.
lCheck oil passages, oil filter and oil pump
for damage or leakage.
lStart the engine after solving the prob-
lem(s) and recheck the oil pressure.
lTighten the oil gallery bolt to specification.
T R..
Oil gallery bolt:
18 Nm (1.8 m • kg, 13 ft • lb)
Adjusting steps:
lTurn in the pilot screw until it is lightly
seated.
lTurn out the pilot screw by the factory-set
number of turns.
Pilot screw:
1-5/8 turns out
* 1-1/2 turns out
(for reference only)
NOTE:
To optimize the fuel flow at a smaller throttle
opening, each machine’s pilot screw has
been individually set at the factory. Before
adjusting the pilot screw, turn it in fully and
count the number of turns. Record this num-
ber as the factory-set number of turns out.

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INSP
ADJ
SPARK ARRESTER CLEANING (For USA)
WARNING
lBe sure the exhaust pipe and muffler are
cool before cleaning the spark arrester.
lDo not start the engine when cleaning the
exhaust system.
1. Remove:
lBolt (spark arrester) 1 1
1
2. Remove:
lSpark arrester 1
Pull the spark arrester out of the muf-
fler.
1
3. Clean:
lSpark arrester
Tap the spark arrester lightly, then use
a wire brush to remove any carbon
deposits.
4. Install:
lSpark arrester
Insert the spark arrester into the muffler
and align the bolt holes.
lBolt (spark arrester)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
SPARK ARRESTER CLEANING (For USA)

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LUBRICATION
EC36a041
LUBRICATION
To ensure smooth operation of all compo-
nents, lubricate your machine during setup,
after break-in, and after every race.
1All control cable
2Brake and clutch lever pivots
3Shift pedal pivot
4Footrest pivot
5Throttle-to-handlebar contact
6Drive chain
7Tube guide cable winding portion
8Throttle cable end
9Clutch cable end
0Decompression cable end
AAA
AAB
CC
Use Yamaha cable lube or equivalent on these
areas.
õUse SAE10W-30 motor oil or suitable chain lubri-
cants.
‚Lubricate the following areas with high quality,
lightweight lithium-soap base grease.
CAUTION:
Wipe off any excess grease, and avoid get-
ting grease on the brake discs.

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INSP
ADJ
ELECTRICAL/SPARK PLUG INSPECTION
EC370000
ELECTRICAL
EC371001
SPARK PLUG INSPECTION
1. Remove:
lSpark plug
2. Inspect:
lElectrode 1
Wear/damage ® Replace.
lInsulator color 2
Normal condition is a medium to light
tan color.
Distinctly different color ® Check the
engine condition.
NOTE:
When the engine runs for many hours at low
speeds, the spark plug insulator will become
sooty, even if the engine and carburetor are in
good operating condition.
3. Measure:
lPlug gap a
Use a wire gauge or thickness gauge.
Out of specification ® Re-gap.
4. Clean the plug with a spark plug cleaner
if necessary.
Spark plug gap:
0.7 ~ 0.8 mm (0.028 ~ 0.031 in)
Standard spark plug:
CR8E (NGK)
U24ESR-N (DENSO)
5. Tighten:
lSpark plug
NOTE:
lBefore installing a spark plug, clean the gas-
ket surface and plug surface.
lFinger-tighten a the spark plug before torqu-
ing to specification b.
T R..13 Nm (1.3 m · kg, 9.4 ft · lb)

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IGNITION TIMING CHECK
IGNITION TIMING CHECK
1. Remove:
lTiming plug 1
2. Attach:
lTiming light
lInductive tachometer
To the spark plug lead.
3. Check:
lIgnition timing
Timing light:
YM-33277-A/90890-03141
Inductive tachometer
YU-8036-1
Engine tachometer:
90890-03113
Checking steps:
lStart the engine and let it warm up. Let the
engine run at the specified speed.
Engine speed:
1,700 ~ 1,900 r/min
lVisually check the stationary pointer a is
within the firing range b on the rotor.
Incorrect firing range ® Check rotor and
pickup assembly.
4. Install:
lTiming plug

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REPLACING THE HEADLIGHT BULBS
REPLACING THE HEADLIGHT BULBS
The following procedure applies to both of the
headlight bulb.
1. Remove:
lNumber plate
Refer to “SEAT, FUEL TANK AND
SIDE COVERS” section in the CHAP-
TER 4.
2. Remove:
lHeadlight bulb holder cover 1
3. Detach:
lHeadlight bulb holder 1
4. Remove:
lHeadlight bulb 2
WARNING
Since the headlight bulb gets extremely
hot, keep flammable products and your
hands away from the bulb unit it has cooled
down.
5. Install:
lHeadlight bulb
Secure the new headlight bulb with the
headlight bulb holder.
CAUTION:
Avoid touching the glass part of the head-
light bulb to keep it free form oil, otherwise
the transparency of the glass, the life of the
bulb and the luminous flux will be
adversely affected. If the headlight bulb
gets soiled, thoroughly clean it with a cloth
moistened with alcohol or lacquer thinner.
6. Attach:
lHeadlight bulb holder
7. Install:
lHeadlight bulb holder cover
8. Install:
lNumber plate
Refer to “SEAT, FUEL TANK AND
SIDE COVERS” section in the CHAP-
TER 4.
New

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ADJUSTING THE HEADLIGHT BEAMS
ADJUSTING THE HEADLIGHT BEAMS
The following procedure applies to both of the
headlight.
1. Adjust:
lHeadlight beam (vertically)
Adjusting steps:
lTurn the adjusting screw 1 in direction a
or b.
Direction a Headlight beam is raised.
Direction b Headlight beam is lowered.