Page 75 of 686

SPEC
2 - 2
GENERAL SPECIFICATIONS
Oil capacity:
Engine oil
Periodic oil change 1.5 L (1.32 Imp qt, 1.59 US qt)
With oil filter replacement 1.6 L (1.41 Imp qt, 1.69 US qt)
Total amount 1.7 L (1.50 Imp qt, 1.80 US qt)
Coolant capacity (including all routes): 1.3 L (1.14 Imp qt, 1.37 US qt)
Air filter: Wet type element
Fuel:
Type Premium unleaded fuel with a research octane
number of 95 or higher. (Except for AUS)
Unleaded fuel only (For AUS)
Tank capacity 12 L (2.64 Imp gal, 3.17 US gal)
(For USA, CDN)
8.0 L (1.76 Imp gal, 2.11 US gal)
(Except for USA, CDN)
Reserve 1.6 L (0.35 Imp gal, 0.42 US gal)
(For USA, CDN)
1.4 L (0.31 Imp gal, 0.37 US gal)
(Except for USA, CDN)
Carburetor:
Type FCR-MX37
Manufacturer KEIHIN
Spark plug:
Type/manufacturer CR8E/NGK
U24ESR-N/DENSO
Gap 0.7 ~ 0.8 mm (0.028 ~ 0.031 in)
Clutch type: Wet, multiple-disc
Transmission:
Primary reduction system Gear
Primary reduction ratio 57/17 (3.353)
Secondary reduction system Chain drive
Secondary reduction ratio 52/13 (4.000)
Transmission type Constant mesh, 5-speed
Operation Left foot operation
Gear ratio: 1st 31/13 (2.385)
2nd 28/16 (1.750)
3rd 28/21 (1.333)
4th 25/24 (1.042)
5th 22/27 (0.815)
Chassis:
Frame type Semi double cradle
Caster angle 27.1˚
Trail 117.4 mm (4.62 in)
2
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2 - 19
SPEC
CABLE ROUTING DIAGRAM
EC240000
CABLE ROUTING DIAGRAM
1
Hose guide
2
Brake hose
3
Voltage regulator
4
Light switch lead
5
Fuel tank breather hose
6
Clamp
7
Oil tank breather hose
8
Engine stop switch lead
9
Sub-wire harness
0
Taillight lead
A
Throttle position sensor lead
B
Neutral switch lead
C
Oil hose
D
Cylinder head breather hose
E
CDI magneto lead
F
Clutch cable
G
Cable guide
H
Carburetor breather hose
I
Carburetor overflow hose
J
Coolant reservoir breather hose
K
Decompression cable
L
CDI unit lead
M
Ignition coil lead
N
Voltage regulator lead
Pass the fuel tank breather hose
behind handlebar, then insert it
into the steering stem hole.
õ
Pass the decompression cable,
engine stop switch lead and light
switch lead under where the oil
hose is attached.
‚
Pass the voltage regulator lead,
engine stop switch lead and light
switch lead over the radiator
hose.
ë
Fasten the engine stop switch
lead and ignition coil lead of the
sub-wire harness.
ä
Fasten the sub-wire harness
and engine stop switch lead.
ì
Pass the cylinder head breather
hose along the right side of the
oil tank breather hose.
í
Fasten the sub-wire harness
and engine stop switch lead in
front of the upper engine brack-
ets.
î
Fasten the sub-wire harness.
é
Pass the sub-wire harness
between the upper engine
brackets.
ï
Fasten the sub-wire harness.
ð
Fasten the throttle position sen-
sor lead.
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2 - 20
SPEC
CABLE ROUTING DIAGRAM
ñ
Pass the carburetor breather
hose and overflow hose
between the connecting rod
and cross tube (frame).
÷
Pass the cylinder head
breather hose through the hose
guide.
ö
Pass the clutch cable through
the cable guide.
¯
Fasten the neutral switch lead
and CDI magneto lead.
¸
Pass the clutch cable along the
inner side of the cylinder head
breather hose.
Î
Pass the cylinder head
breather hose along the inner
side of the radiator hose.
å
Pass the clutch cable in front of
the radiator mounting boss.
ê
Fit the brake hose into the
guides on the protector.
æ
Fasten the ground lead
together with the ignition coil
lead.
è
Do not allow the engine stop
switch leads and light switch
lead to slacken between the
two clamps.
×
Pass the decompression cable
along the right side of the cylin-
der head breather hose.
ã
Pass the clutch cable through
the cable guides.
ô
Pass the carburetor breather
hoses and overflow hose so
that all there hoses do not con-
tact the rear shock absorber.
ç
Position each lead at the lower
left of the main tube (frame).
Page 158 of 686

3 - 1
INSP
ADJ
MAINTENANCE INTERVALS
EC300000
REGULAR INSPECTION AND ADJUSTMENTS
MAINTENANCE INTERVALS
The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind
that such factors as weather, terrain, geographical location, and individual usage will alter the
required maintenance and lubrication intervals. If you are a doubt as to what intervals to follow in
maintaining and lubricating your machine, consult your Yamaha dealer.
ItemAfter
break-inEvery
race
Every
third race
or
500 km
(300 mi)Every
fifth race
or
1,000 km
(600 mi)
As re-
quiredRemarks
ENGINE OIL
Replace
Inspect
c
cc
c
OIL FILTER ELEMENT, OIL STRAINER
Clean
c
VALVES
Check the valve clearances.
Inspect
Replace
c
c
c
c
The engine must be cold.
Check the valve seats
and valve stems for wear.
VALVE SPRINGS
Inspect
Replace
c
c
Check the free length and
the tilt.
VALVE LIFTERS
Inspect
Replace
c
c
Check for scratches and
wear.
CAMSHAFTS
Inspect
Replace
c
c
Inspect the camshaft sur-
face.
TIMING CHAIN SPROCKETS, TIMING
CHAIN
Inspect
Replace
c
c
Check for wear on the
teeth and for damage.
PISTON
Inspect
Clean
Replace
c
c
c
c
Inspect crack
Remove carbon
PISTON RING
Inspect
Replace
c
c
c
Check ring end gap
PISTON PIN
Inspect
Replace
c
c
CYLINDER HEAD
Inspect and clean
c
Remove carbon
Change gasket
CYLINDER
Inspect and clean
Replace
c
c
Inspect score marks
Inspect wear
CLUTCH
Inspect and adjust
Replace
c
c
c
Inspect housing, friction
plate, clutch plate and
spring
TRANSMISSION
Inspect
Replace bearing
c
c
3
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3 - 4
INSP
ADJ
PRE-OPERATION INSPECTION AND MAINTENANCE
EC320000
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation, practice or a race, make sure the machine is in good operating
condition.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
CoolantCheck that coolant is filled up to the radiator cap.
Check that the coolant level is correct in the coolant reservoir.
Check the cooling system for leakage.P.3-5 ~ 9
FuelCheck that a fresh gasoline is filled in the fuel tank. Check the
fuel line for leakage.P.1-13
Engine oilCheck that the oil level is correct. Check the crankcase and
frame oil line for leakage.P.3-14 ~ 17
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-9
Throttle grip/HousingCheck that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.P.3-10 ~ 11
Brakes Check the play of front brake and effect of front and rear brake. P.3-26 ~ 32
Drive chainCheck drive chain slack and alignment. Check that the drive
chain is lubricated properly.P.3-33 ~ 35
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-43 ~ 44
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-44 ~ 45
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-35 ~ 42
Cables (wires)Check that the clutch and throttle cables move smoothly. Check
that they are not caught when the handlebars are turned or
when the front forks travel up and down.—
Exhaust pipeCheck that the exhaust pipe is tightly mounted and has no
cracks.P.4-2
Rear wheel sprocket Check that the rear wheel sprocket tightening bolt is not loose. P.3-33
Lubrication Check for smooth operation. Lubricate if necessary. P.3-46
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-18
Lead connectorsCheck that the CDI magneto, CDI unit, and ignition coil are con-
nected tightly.P.1-6
SettingsIs the machine set suitably for the condition of the racing course
and weather or by taking into account the results of test runs
before racing? Are inspection and maintenance completely
done?P.7-1 ~ 22
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3 - 7
INSP
ADJ
RADIATOR CAP INSPECTION
CAUTION:
lDo not mix more than one type of ethyl-
ene glycol antifreeze containing corro-
sion inhibitors for aluminum engine.
lDo not use water containing impurities or oil.
10. Install:
lRadiator cap
11. Fill:
lCoolant reservoir
Midway a between maximum and min-
imum marks on the tank.
12. Install:
lCoolant reservoir cap
13. Start the engine and let it warm up for
several minutes.
14. Turn off the engine and inspect the cool-
ant level.
Refer to “COOLANT LEVEL INSPEC-
TION” section.
NOTE:
Before checking the coolant level wait a few
minutes until the coolant settles.Handling notes of coolant:
The coolant is harmful so it should be han-
dled with special care.
WARNING
lWhen coolant splashes to your eye.
Thoroughly wash your eye with water
and see your doctor.
lWhen coolant splashes to your clothes.
Quickly wash it away with water and
then with soap.
lWhen coolant is swallowed.
Quickly make him vomit and take him
to a doctor.
LOWFULLCOOLANTa
EC355000
RADIATOR CAP INSPECTION
1. Inspect:
lSeal (radiator cap) 1
lValve and valve seat 2
Crack/damage ® Replace.
Exist fur deposits 3 ® Clean or
replace.
Page 190 of 686
3 - 13
INSP
ADJ
AIR FILTER CLEANING
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 oil to the ele-
ment.
NOTE:
Squeeze out the excess oil. Element should
be wet but not dripping.
8. Install:
lAir filter guide 1
NOTE:
Align the projection a on air filter guide with
the hole b in air filter element.
9. Apply:
lLithium soap base grease
On the matching surface a on air filter
element.
Page 192 of 686
3 - 14
INSP
ADJ
10. Install:
lAir filter element 1
lWasher
lFitting bolt
NOTE:
Align the projection a on filter guide with the
hole b in air filter case.
T R..2 Nm (0.2 m · kg, 1.4 ft · lb)
ENGINE OIL LEVEL INSPECTION
1. Start the engine, warm it up for several
minutes, and then turn off the engine and
wait for five minutes.
2. Place the machine on a level place and
hold it up on upright position by placing
the suitable stand under the engine.
3. Remove:
lOil tank cap 1
4. Inspect:
lOil level
Oil level should be between maximum
a and minimum b marks.
Oil level is low ® Add oil to proper
level.
NOTE:
When inspecting the oil level, do not screw the
oil tank cap into the oil tank. Insert the gauge
lightly.
ENGINE OIL LEVEL INSPECTION