Page 75 of 656

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): 0.9 L (0.79 Imp qt, 0.95 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 8.0 L (1.76 Imp gal, 2.11 US gal)
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 48/13 (3.692)
Transmission type Constant mesh, 5-speed
Operation Left foot operation
Gear ratio: 1st 30/14 (2.143)
2nd 28/16 (1.750)
3rd 29/20 (1.450)
4th 27/22 (1.227)
5th 25/24 (1.042)
Chassis:
Frame type Semi double cradle
Caster angle 27.1˚
Trail 117.4 mm (4.62 in)
Tire:
Type With tube
Size (front) 80/100-21 51M (For USA, CDN, ZA, AUS, NZ
and F)
80/100-21 MT320 (For EUROPE except F)
Size (rear) 100/90-19 57M (For USA, CDN, ZA, AUS, NZ
and F)
100/90-19 MT320 (For EUROPE except F)
Tire pressure (front and rear) 100 kPa (1.0 kg/cm
2
, 15 psi)
2
Page 142 of 656

2 - 18
SPEC
CABLE ROUTING DIAGRAM
EC240000
CABLE ROUTING DIAGRAM
1
Hose guide
2
Brake hose
3
Fuel tank breather hose
4
Engine stop switch lead
5
Oil tank breather hose
6
Sub-wire harness
7
Neutral switch lead
8
Cable guide
9
Cylinder head breather hose
0
CDI magneto lead
A
Radiator breather hose
B
Carburetor breather hose
C
Carburetor overflow hose
D
Ignition coil lead
E
CDI unit lead
Pass the fuel tank breather hose
between the handlebar and ten-
sion bar, then insert its end into
the hole of the number plate.
õ
Fasten the engine stop switch
lead and ignition coil lead of the
sub-wire harness.
‚
Fasten the sub-wire harness
and engine stop switch lead.
Fasten the engine stop switch
lead at its protecting tube.
ë
Fasten the sub-wire harness
and engine stop switch leads.
ä
Pass the sub-wire harness
between upper engine brackets.
ì
Fasten the sub-wire harness.
í
Fasten the throttle position sen-
sor lead.
î
Pass the carburetor breather
hose and overflow hose
between the connecting rod and
cross tube (frame).
é
Fasten the neutral switch lead
on the oil hose.
ï
Pass the clutch cable through
the cable guide.
ð
Fasten the cylinder head
breather hose and neutral switch
lead.
ñ
Fasten the neutral switch lead.
Page 144 of 656
2 - 19
SPEC
CABLE ROUTING DIAGRAM
÷
Pass the cylinder head
breather hose through the hose
guide.
ö
Fasten the neutral switch lead
and CDI magneto lead.
¯
Pass the clutch cable on the
inside the cylinder head
breather hose.
¸
Pass the clutch cable in front of
the radiator mounting boss.
Î
Fit the brake hose into the
guides on the protector.
å
Pass the carburetor breather
hoses and overflow hose so
that all there hoses do not con-
tact the rear shock absorber.
ê
Fasten the ground lead
together with the ignition coil.
æ
Do not allow the engine stop
switch leads to slacken
between the two clamps.
è
Pass the clutch cable through
the cable guides.
Ã
Position each lead at the lower
left of the main tube (frame).
Page 146 of 656
2 - 20
SPEC
1
Spark plug lead
2
Ignition coil
3
CDI unit
4
CDI unit band
5
Throttle cable (return)
6
Throttle cable (pull)
7
Cable guide
8
CDI unit lead
9
CDI unit stay
0
Radiator breather hose
A
Radiator hose 4
Pass the CDI unit lead
between the radiator hose and
radiator mounting boss.
õ
Pass the throttle cables
through cable guide.
‚
Pass the throttle cables under
the radiator mounting boss.
ë
Insert the CDI unit band over
the CDI unit stay (frame) as far
as possible.
ä
Pass the radiator breather
hose in front of the radiator
mounting rear boss and at the
left of the chassis. And then,
pass it between the radiator
hose 4 and down tube (frame)
and between the engine and
lower engine guard.
CABLE ROUTING DIAGRAM
Page 152 of 656

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
(or
500 km)Every
fifth
(or
1,000 km)
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
Page 164 of 656

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 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.3-13 ~ 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.3-25 ~ 31
Drive chainCheck drive chain slack and alignment. Check that the drive
chain is lubricated properly.P.3-32 ~ 34
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-42 ~ 43
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-43 ~ 44
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-34 ~ 41
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.3-32
Lubrication Check for smooth operation. Lubricate if necessary. P.3-45
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
Page 172 of 656
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.
7. Install:
lRadiator cap
Start the engine and warm it up for a
several minutes.
8. Check:
lCoolant level
Coolant level low ® Add coolant. 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.
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 184 of 656
3 - 13
INSP
ADJ
ENGINE OIL LEVEL INSPECTION
3. Inspect:
lAir filter element
Damage ® Replace.
4. 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.
5. Install:
lAir filter guide 1
NOTE:
Align the projection a on air filter guide with
the hole b in air filter element.
6. Apply:
lLithium soap base grease
On the matching surface a on air filter
element.
7. 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.