IMPORTANT INFORMATION
1-7
EAS20180
IMPORTANT INFORMATION
EAS2GC1020PREPARATION FOR REMOVAL AND DIS-
ASSEMBLY
1. Before the jobs, completely remove mud, dust, and the like in order to prevent the en-
try of them into the inside during the jobs.
• Before cleaning with high-pressure water of washers, cover the following parts.
Air duct
Silencer exhaust port
Drain hole on the cylinder head (right side)
Hole under the water pump housing
2. Use proper special tools and equipment. See “SPECIAL TOOLS”.
3. During disassembly, check and measure the required parts, and make a record of them
so that you may refer to the record when in-
stalling them. Moreover, arrange gears, cyl-
inders, pistons, and other parts for each
section so as not to confuse or lose them. 4. During disassembly, clean each of the parts,
and store them in trays for each section.
5. Flammable. Keep servicing areas away from any source of fire.
6. During servicing, take special care not to re-
ceive an injury or a burn on the engine, the
exhaust pipe, the silencer, or the like.
7. If coolant is left adhered to the chassis, paint
and plating will be damaged. Therefore,
rinse it out with water in good time.
EWA
WARNING
Coolant is potentially harmful and should
be handled with special care.
• If it enters your eyes, wash it away with wa-ter enough and then get medical attention
• If it splashes on your skin or clothes,
quickly wash it away with water and then
with soapy water.
• If it is swallowed, immediately induce vom-
iting and get medical attention.
EAS2GC1021REPLACEMENT PARTS
Make sure that the parts and grease or oil to be
used for repair of the vehicle, including periodic
replacement parts, are new YAMAHA genuine
parts and recommended parts.
Do not use any used parts, because these may
not be genuine though they have similar ap-
pearances or because the quality may be
changed by aging.
MOTORCYCLE CARE AND STORAGE
1-34
EAS2GC1058
MOTORCYCLE CARE AND STOR-
AGE
EAS2GC1059CARE
While the open design of a motorcycle reveals
the attractiveness of the technology, it also
makes it more vulnerable. Rust and corrosion
can develop even if high-quality components
are used. A rusty exhaust pipe may go unno-
ticed on a car, however, it detracts from the
overall appearance of a motorcycle. Frequent
and proper care does not only comply with the
terms of the warranty, but it will also keep your
motorcycle looking good, extend its life and op-
timize its performance.
Before cleaning
1. Cover the muffler outlet with a plastic bag af-ter the engine has cooled down.
2. Make sure that all caps and covers as well as all electrical coup lers and connectors, in-
cluding the spark plug cap, are tightly in-
stalled.
3. Remove extremely stubborn dirt, like oil
burnt onto the crankcase, with a degreasing
agent and a brush, but never apply such
products onto seals, gaskets, sprockets, the
drive chain and wheel axles. Always rinse
the dirt and degreaser off with water.
Cleaning
ECA
NOTICE
• Avoid using strong acidic wheel cleaners, especially on spoked wheels. If such prod-
ucts are used on hard-to-remove dirt, do
not leave the cleaner on the affected area
any longer than instructed. Also, thor-
oughly rinse the area off with water, imme-
diately dry it, and then apply a corrosion
protection spray.
• Improper cleaning can damage plastic parts (such as cowlings, panels, wind-
shields, headlight lenses, meter lenses,
etc.) and the mufflers. Use only a soft,
clean cloth or sponge with water to clean
plastic. However, if the plastic parts can-
not be thoroughly cleaned with water, di-
luted mild detergent with water may be
used. Be sure to rinse off any detergent
residue using plenty of water, as it is
harmful to plastic parts. • Do not use any harsh chemical products
on plastic parts. Be sure to avoid using
cloths or sponges which have been in con-
tact with strong or abrasive cleaning prod-
ucts, solvent or thinner, fuel (gasoline),
rust removers or inhibitors, brake fluid,
antifreeze or electrolyte.
• Do not use high-pressure washers or steam-jet cleaners since they cause water
seepage and deterioration in the following
areas: seals (of wheel and swingarm bear-
ings, fork and brakes), electric compo-
nents (couplers, connectors, instruments,
switches and lights), breather hoses and
vents.
• For motorcycles equipped with a wind-
shield: Do not use strong cleaners or hard
sponges as they will cause dulling or
scratching. Some cleaning compounds for
plastic may leave scratches on the wind-
shield. Test the product on a small hidden
part of the windshield to make sure that it
does not leave any marks. If the wind-
shield is scratched, use a quality plastic
polishing compound after washing.
After normal use
Remove dirt with warm water, a mild detergent,
and a soft, clean sponge, and then rinse thor-
oughly with clean water. Use a toothbrush or
bottlebrush for hard-to-reach areas. Stubborn
dirt and insects will come off more easily if the
area is covered with a wet cloth for a few min-
utes before cleaning.
After riding in the rain, near the sea or on salt-
sprayed roads
Since sea salt or salt sprayed on roads during
winter are extremely corrosive in combination
with water, carry out the following steps after
each ride in the rain, near the sea or on salt-
sprayed roads.
TIP
Salt sprayed on roads in the winter may remain
well into spring.
1. Clean the motorcycle with cold water and a mild detergent, after the engine has cooled
down.
NOTICE: Do not use warm water since it
increases the corrosive action of the salt.
CHASSIS SPECIFICATIONS
2-9
Rear suspensionType Swingarm (link suspension)
Spring/shock absorber type Coil spring/Gas-hydraulic damper
Rear shock absorber assembly travel 126.0 mm (4.96 in)
Spring free length 275.0 mm (10.83 in)
Spring installed length 263.0 mm (10.35 in)
Spring rate K1 56.00 N/mm (5.71 kgf/mm, 319.76 lbf/in)
Spring stroke K1 0.0–150.0 mm (0.00–5.91 in)
Optional spring available Yes
Enclosed gas/air pressure (STD) 980 kPa (9.8 kgf/cm
2, 139.4 psi)
Spring preload adjusting positions
Minimum Position in which the spring is turned in 1.5 mm
(0.06 in) from its free length.
Standard Position in which the spring is turned in 12 mm
(0.47 in) from its free length.
Maximum Position in which the spring is turned in 18 mm
(0.71 in) from its free length.
Rebound damping adjusting positions Minimum 30 clicks out*
Standard 14 clicks out*
Maximum Fully turned in
* With the adjuster fully turned in
Compression damping setting
(for fast compression damping)Minimum 2 turns out*
Standard 1-3/4 turns out*
Maximum Fully turned in
* With the adjuster fully turned in
Compression damping setting
(for slow compression damping)Minimum 20 clicks out*
Standard 10 clicks out*
Maximum Fully turned in
* With the adjuster fully turned in
Swingarm Swingarm end free play limit (radial) 1.0 mm (0.04 in)
Swingarm end free play limit (axial) 0.2–0.9 mm (0.01–0.04 in)
Drive chainSize/manufacturer DID520VM2/DAIDO
Number of links 114
Drive chain slack (on a suitable stand) 50.0–60.0 mm (1.97–2.36 in)
15-link length limit 239.3 mm (9.42 in)
PRE-OPERATION INSPECTION AND MAINTENANCE
3-9
EAS2GC1079
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.
EAS2GC1080GENERAL INSPECTION AND MAINTENANCE
TIP
Perform usual maintenance enough so that, in the race course, a confirmation of that and simple set-
ting adjustments may only be left, in order to get enough time to use effectively.ITEM inspect Page
Coolant Check that coolant is filled up to the radiator cap.
Check the cooling system for leakage. 3-10 – 12
Fuel Check that a fresh gasoline is filled in the fuel tank.
Check the fuel line for leakage. 1-28
Engine oil Check that the oil level is correct. Check the crank-
case and oil line for leakage. 3-16 – 18
Gear shifter and clutch Check that gears can be shifted correctly in order and
that the clutch operates smoothly. 3-12 – 13
Throttle grip/Housing Check that the throttle grip operation and free play
are correctly adjusted. Lubricate the throttle grip and
housing, if necessary. 3-13 – 14
Brakes Check the play of front brake and effect of front and
rear brake. 3-25 – 31
Drive chain Check drive chain slack and alignment. Check that
the drive chain is lubricated properly. 3-31
5-69 – 70
Wheels Check for excessive wear and tire pressure. Check
for loose spokes and have no excessive play. 3-36 – 37
Steering Check that the handlebar can be turned smoothly and
have no excessive play. 3-37 – 38
Front forks and rear
shock absorber Check that they operate smoothly and there is no oil
leakage.
3-31 – 36
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 pipe Check that the exhaust pipe is tightly mounted and
has no cracks. 3-15 – 16
Rear wheel sprocket Check that the rear wheel sprocket tightening bolt is
not loose. 5-10 – 11
Lubrication Check for smooth operation. Lubricate if necessary. 3-14
3-38 – 39
Bolts and nuts Check the chassis and engine for loose bolts and
nuts. 1-32 – 33
Lead connectors Check that the AC magneto, ECU and ignition coil are
connected tightly. 1-9 – 12
Settings Is the machine set suitably for the condition of the rac-
ing course and weather or by taking into account the
results of test runs before racing? Are inspection and
maintenance completely done?
4-1 – 8
ENGINE
3-19
EAS2GC1098ADJUSTING THE ENGINE IDLING SPEED
TIP
• Because the air pressure is lower at high alti-tudes, the air-fuel mixture will become richer.
If the idling speed is low, turn the starter knob/
idle screw a few clicks counterclockwise to in-
crease the speed before the adjustment.
• Before adjusting the engine idling speed, make sure that the air filter element is not
clogged, the engine compression is proper,
and the throttle grip free play is proper.
• Adjust the engine idling speed with the starter
knob/idle screw pushed in completely.
1. Start the engine, and warm this up until the oil has reached the specified temperature.
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. Attach the pocket tester with temperature probe “1” to the oil drain bolt.
3. Install: • Digital tachometer
TIP
Get the high tension cord “1” of the ignition coil
pinched in the detector “a” of the digital tachom-
eter.
4. Measure:• Engine idling speed
Out of specification Regulate.
5. Adjust: • Engine idling speed
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Turn the starter knob/idle screw “1” in the di- rection of “a” or “b” to make an adjustment.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
Oil temperature70–80 °C (158–176 °F)
Digital tachometer 90890-06760
Digital tachometer YU-39951-B
1
Engine idling speed 1900–2100 r/min
Direction “a” Engine idling speed De-
creases.
Direction “b” Engine idling speed In-
creases.
1
1
a
a
1
b
a
CHASSIS
4-2
• Under a stony or a hard road condition, the tire pressure should be hi gher to prevent a flat
tire.
EAS2GC1140FRONT FORK SETTING
The front fork setting should be made depend-
ing on the rider’s feeli ng of an actual run and
the circuit conditions.
The front fork setting includes the following
three factors:
1. Setting of air spring characteristics • Change the fork oil amount.
2. Setting of spring preload • Change the spring.
3. Setting of damping force
• Change the compression damping force.
• Change the rebound damping force.The spring acts on the load and the damping
force acts on the cushion travel speed.
EAS2GC1141CHANGE IN AMOUNT AND CHARACTERIS-
TICS OF FORK OIL
Damping characteristic near the final stroke
can be changed by changing the fork oil
amount.
EWA
WARNING
Adjust the oil amount in 5 cm3 (0.2 US oz,
0.2 Imp.oz) increments or decrements. Too
small oil amount causes the front fork to
produce a noise at full rebound or the rider
to feel some pressure on his hands or body.
Alternatively, too large oil amount will
cause the air spring characteristics to have
a tendency to be stiffer with the consequent
deteriorated performance and characteris-
tics. Therefore, adjust the front fork within
the specified range.
EAS2GC1142SETTING OF SPRING AFTER REPLACE-
MENT
As the front fork setting can be easily affected
by the rear suspension, take care so that the
front and the rear are balanced (in position etc.)
when setting the front fork.
1. Use of soft spring
• Change the rebound damping force.Turn out one or two clicks.
• Change the compression damping force.
Turn in one or two clicks.
TIP
Generally a soft spring gives a soft riding feel-
ing. Rebound damping tends to become stron-
ger and the front fork may sink deeply over a
series of gaps.
2. Use of stiff spring• Change the rebound damping force.
Turn in one or two clicks.
• Change the compression damping force. Turn out one or two clicks.
Extent of adjustment
100–120 kPa (1.00–1.20 kgf/cm
2,
15–18 psi)
Standard oil amount 345 cm
3 (11.66 US oz, 12.14
lmp.oz)
Extent of adjustment 300–365 cm
3 (10.14–12.34 US
oz, 10.58–12.87 Imp.oz)
A. Air spring characteristics in relation to oil amount change
B. Load
C. Stroke
1. Max. oil amount
2. Standard oil amount
3. Min. oil amount
TROUBLESHOOTING
10-2
Electrical system
1. Battery• Discharged battery
• Faulty battery
2. Spark plug • Incorrect spark plug gap
• Incorrect spark plug heat range
• Fouled spark plug
• Worn or damaged electrode
• Worn or damaged insulator
• Faulty spark plug cap
3. Ignition coil
• Broken or shorted primary or secondary coil
• Cracked or broken ignition coil
4. Ignition system • Faulty ECU
• Faulty crankshaft position sensor
• Broken generator rotor woodruff key
EAS2GC1410POOR MEDIUM-AND-HIGH-SPEED PER-
FORMANCE
Refer to “STARTING FAILURES” on page 10-
1.
Engine
1. Air filter
• Clogged air filter element
Fuel system
1. Fuel pump • Faulty fuel pump
2. Throttle body
• Defective throttle body
3. ECU • Faulty ECU
EAS2GC1411SHIFTING IS DIFFICULT
Refer to “CLUTCH” on page 6-41.
EAS2GC1412SHIFT PEDAL DOES NOT MOVE
Engine
1. Shift shaft
• Bent shift shaft
2. Shift drum and shift forks • Foreign object in a shift drum groove
• Seized shift fork
• Bent shift fork guide bar
3. Transmission
• Seized transmission gear
• Foreign object between transmission gears
• Improperly assembled transmission
EAS2GC1413
JUMPS OUT OF GEAR
Engine
1. Shift shaft• Incorrect shift pedal position
• Improperly returned stopper lever
2. Shift forks
• Worn shift fork
3. Shift drum • Incorrect axial play
• Worn shift drum groove
4. Transmission • Worn gear dog
EAS2GC1414CLUTCH SLIPS
Engine
1. Clutch• Improperly assembled clutch
• Loose or fatigued clutch spring
• Worn friction plate
• Worn clutch plate
2. Engine oil
• Incorrect oil level
• Incorrect oil viscosity (low)
• Deteriorated oil
EAS2GC1415CLUTCH DRAGS
Engine
1. Clutch• Unevenly tensioned clutch springs
• Warped pressure plate
• Bent clutch plate
• Swollen friction plate
• Bent clutch push rod
• Damaged clutch boss
• Burnt primary driven gear bushing
2. Engine oil • Incorrect oil level
• Incorrect oil viscosity (high)
• Deteriorated oil
EAS2GC1416OVERHEATING
Engine
1. Cylinder head and piston• Heavy carbon buildup
• Clogged coolant passages
2. Engine oil
• Incorrect oil level
• Incorrect oil viscosity
• Inferior oil quality
TROUBLESHOOTING
10-3
Cooling system
1. Coolant• Low coolant level
2. Radiator • Damaged or leaking radiator
• Faulty radiator cap
• Bent or damaged radiator fin
3. Water pump • Damaged or faulty water pump
• Damaged hose
• Improperly connected hose
• Damaged pipe
• Improperly connected pipe
Fuel system
1. Throttle body • Damaged or loose throttle body joint
2. Air filter • Clogged air filter element
Chassis
1. Brake(s) • Dragging brake
Electrical system
1. Spark plug • Incorrect spark plug gap
• Incorrect spark plug heat range
2. Ignition system • Faulty ECU
• Faulty coolant temperature sensor
EAS2GC1417OVERCOOLING
Cooling system
1. Coolant temperature sensor• Faulty coolant temperature sensor
EAS2GC1418POOR BRAKING PERFORMANCE
Chassis
1. Brake(s)• Worn brake pad
• Worn brake disc
• Air in hydraulic brake system
• Leaking brake fluid
• Defective master cylinder kit
• Faulty brake caliper kit
• Faulty brake caliper seal
• Loose union bolt
• Damaged brake hose
• Oil or grease on the brake disc
• Oil or grease on the brake pad
• Incorrect brake fluid level
EAS2GC1419FRONT FORK OIL LEAKING
Chassis
1. Front fork• Bent, damaged, or rusty inner tube
• Cracked or damaged outer tube
• Improperly installed oil seal
• Damaged oil seal lip
• Incorrect oil level (high)
• Loose damper rod assembly bolt
• Damaged damper rod assembly bolt copper
washer
• Cracked or damaged cap bolt O-ring
EAS2GC1420FAULTY FRONT FORK LEGS
Chassis
1. Front fork • Bent or damaged inner tube
• Bent or damaged outer tube
• Broken fork spring
• Bent or damaged damper rod
• Incorrect oil viscosity
• Incorrect oil level
EAS2GC1421UNSTABLE HANDLING
Chassis
1. Handlebar• Bent or improperly installed handlebar
2. Steering head components • Improperly installed upper bracket
• Improperly installed lower bracket(improperly tightened ring nut)
• Bent steering stem
• Damaged ball bearing or bearing race
3. Front fork leg (s) • Uneven oil levels (both front fork legs)
• Unevenly tensioned fork spring (both front fork legs)
• Broken fork spring
• Bent or damaged inner tube
• Bent or damaged outer tube
4. Swingarm • Worn bearing or bushing
• Bent or damaged swingarm
5. Rear shock absorber assembly (-ies) • Faulty rear shock absorber spring
• Leaking oil or gas
6. Tire (s) • Uneven tire pressures (front and rear)
• Incorrect tire pressure
• Uneven tire wear