ENGINE
3-20
EAS2GC1099ADJUSTING THE VALVE CLEARANCE
TIP
• This section is intended for those who have basic knowledge and skill concerning the ser-
vicing of Yamaha motorcycles (e.g., Yamaha
dealers, service engineers, etc.). Those who
have little knowledge and skill concerning ser-
vicing are requested not to undertake inspec-
tion, adjustment, disassembly, or reassembly
only by reference to this manual. It may lead
to servicing trouble and mechanical damage.
• Make sure that the valve clearance is checked or adjusted while the engine is cold
(at room temperature).
• While the valve clearance is checked or ad- justed, make sure that the piston is positioned
in the top dead center (TDC).
1. Remove: • Seat
• Side cover (left/right)
• Air scoop (left/right)Refer to “GENERAL CHASSIS” on page 5-
1.
• Fuel tank
Refer to “FUEL TANK” on page 8-1.
•ECU
2. Remove:
• Spark plug
• Cylinder head coverRefer to “CAMSHAFT” on page 6-11.
3. Remove: • Timing mark accessing screw “1”
• Crankshaft end accessing screw “2”
• O-ring 4. Check:
• Valve clearanceOut of specification Regulate.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Turn the crankshaft counterclockwise with a
wrench.
b. Align the top dead center (TDC) mark “a” on the rotor with the alignment mark “b” on the
crankcase cover.
TIP
Check that the alignment mark “c” on the cam-
shaft sprocket and the alignment mark “d” on
the intake camshaft sprocket are aligned with
the edge of the cylinder head.
c. Measure the valve clearance “e” using a
thickness gauge “1”.
TIP
Record the measured reading if the clearance
is incorrect.
12
Valve clearance (cold)Intake 0.13–0.20 mm (0.0051–0.0079 in)
Exhaust 0.18–0.25 mm (0.0071–0.0098 in)
ab
d
c
CHASSIS
3-34
EAS2GC1116CHECKING THE SWINGARM OPERATION
1. Check:• Swingarm smooth action
• Swingarm free playRefer to “SWINGARM” on page 5-65.
EAS2GC1117CHECKING THE REAR SUSPENSION
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:• Rear shock absorber assemblyGas leaks/oil leaks Replace the rear
shock absorber assembly.
Refer to “REAR SHOCK ABSORBER AS-
SEMBLY” on page 5-58.
3. Check: • Rear shock absorber assembly smooth ac-tion
• Rear suspension link smooth action Sit astride the seat and shake your body up
and down several times to check whether
the rear shock absorber assembly operates
smoothly.
Unsmooth operation Correct or replace.
Refer to “REAR SHOCK ABSORBER AS-
SEMBLY” on page 5-58.
EAS2GC1118ADJUSTING THE REAR SHOCK ABSORB-
ER ASSEMBLY
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. Spring preload
ECA
NOTICE
Do not turn the adjuster forcibly beyond its
adjusting range.
1. Remove:
• Rear frameRefer to “REAR SHOCK ABSORBER AS-
SEMBLY” on page 5-58.
2. Adjust: • Spring preload
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Loosen the locknut “1”.
b. Loosen the adjuster “2” until there is some clearance between the spring and the ad-
juster.
c. Measure the spring free length “a”.
d. Turn the adjuster in the direction of “b” or “c” to make an adjustment.
Direction “b”Spring preload is increased (suspen-
sion is harder).
Direction “c” Spring preload is decreased (suspen-
sion is softer).
Spring preload adjusting positionsMinimum 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.
CHASSIS
4-3
TIP
Generally a stiff spring gives a stiff riding feel-
ing. Rebound damping tends to become weak-
er, resulting in lack of a sense of contact with
the road surface or in a vibrating handlebar.
EAS2GC1143FRONT FORK SETTING PARTS
• Front fork spring “1”
TIP
The I.D. mark (slits) “a” is proved on the end of
the spring.
EAS2GC1144REAR SUSPENSION SETTING
The rear shock absorber setting should be
made depending on the rider’s feeling of an ac-
tual run and the circuit conditions.
The rear suspension setting includes the fol-
lowing two factors:
1. Setting of spring preload • Change the set length of the spring.
• Change the spring.
2. Setting of damping force
• Change the rebound damping force.
• Change the compression damping force.
EAS2GC1145CHOOSING SET LENGTH
1. Place a stand or a block under the engine to put the rear wheel above the floor, and mea-
sure the length “a” between the rear wheel
axle center and the rear fender holding bolt.
2. Remove the stand or block from the engine and, with a rider astride the seat, measure
the sunken length “b” between the rear
wheel axle center and the rear fender hold-
ing bolt.
3. Loosen the locknut “1” and make adjustment by turning the adjuster “2” to achieve the
standard figure from the subtraction of the
length “b” from the length “a”.
Type
Spring
rate N/ mm Part number I.D.
Mark
(slits)
SOFT 4.1 2GB-23141-A0 |||
4.2 2GB-23141-B0 ||||
4.3 2GB-23141-C0 |||||
4.4 2GB-23141-D0 |-|
STD 4.5 2GB-23141-40 —
2GB-23141-E0 |-||
STIFF 4.6 33D-23141-30 |-|||
a
1
Standard figure90–100 mm (3.5–3.9 in)
CHASSIS
4-7
EAS2GC1149SUSPENSION SETTING (REAR SHOCK ABSORBER)
TIP
• If any of the following symptoms is experienced with the standard position as the base, make reset-ting by reference to the adjustment procedure given in the same chart.
• Adjust the rebound damping in 2- click increments or decrements.
• Adjust the low compression damping in 1-click increments or decrements.
• Adjust the high compression damping in 1/6 turn increments or decrements.Low front, tend-
ing to lower
front posture
Compression
damping force
Turn adjuster clockwise (about
2 clicks) to increase damping.
Rebound
damping force Turn adjuster counterclock-
wise (about 2 clicks) to de-
crease damping.
Balance with
rear end Set sunken length for 95–100
mm (3.7–3.9 in) when one
passenger is astride seat (low-
er rear posture).
Oil amount Increase oil amount by about 5 cm
3 (0.2 US oz, 0.2 Imp.oz).
“Obtrusive”
front, tending to
upper front pos-
ture Compression
damping force
Turn adjuster counterclock-
wise (about 2 clicks) to de-
crease damping.
Balance with
rear end Set sunken length for 90–95
mm (3.5–3.7 in) when one
passenger is astride seat (up-
per rear posture).
Spring Replace with soft spring.
Oil amount Decrease oil amount by about 5–10 cm
3 (0.2–0.3 US oz, 0.2–
0.4 Imp.oz).
Symptom Section
Check Adjust
Jump Large
gap Medi-
um
gap Small
gap
Stiff, tending to
sink Rebound
damping force
Turn adjuster counterclock-
wise (about 2 clicks) to de-
crease damping.
Spring set
length Set sunken length for 90–100
mm (3.5–3.9 in) when one
passenger is astride seat.
Spongy and un-
stable Rebound
damping force
Turn adjuster clockwise (about
2 clicks) to increase damping.
Low compres-
sion damping Turn adjuster clockwise (about
1 click) to increase damping.
Spring Replace with stiff spring.
Symptom
Section
Check Adjust
Jump Large
gap Medi-
um
gap Small
gap
GENERAL CHASSIS
5-1
EAS2GC1150
TIP
This section is intended for those who have basic knowledge and skill concerning the servicing of
Yamaha motorcycles (e.g., Yamaha dealers, serv ice engineers, etc.). Those who have little knowl-
edge and skill concerning servicing are requested not to undertake inspection, adjustment, disas-
sembly, or reassembly only by reference to this manual. It may lead to servicing trouble and
mechanical damage.
EAS2GC1151
GENERAL CHASSIS
Removing the seat and side cover
OrderPart name Q’tyRemarks
1 Seat 1
2 Air scoop (left) 1
3 Air scoop (right) 1
4 Side cover (left) 1
5 Side cover (right) 1
6 Rear fender 1
For installation, reverse the removal proce-
dure.
4
(2)
65
1
3
2
7 Nm (0.7 m kgf, 5.1 ft Ibf)T.R.
7 Nm (0.7 m kgf, 5.1 ft Ibf)T.R.
7 Nm (0.7 m kgf, 5.1 ft Ibf)T.R.
22 Nm (2.2 m kgf, 16 ft Ibf)T.R.
1.3 Nm (0.13 m kgf, 0.94 ft Ibf)T.R.16 Nm (1.6 m kgf, 12 ft Ibf)T.R.
RADIATOR
7-1
EAS2GC1328
TIP
This section is intended for those who have basic knowledge and skill concerning the servicing of
Yamaha motorcycles (e.g., Yamaha dealers, serv ice engineers, etc.). Those who have little knowl-
edge and skill concerning servicing are requested not to undertake inspection, adjustment, disas-
sembly, or reassembly only by reference to this manual. It may lead to servicing trouble and
mechanical damage.
EAS2GC1329
RADIATOR
Removing the radiator
OrderPart name Q’tyRemarks
Coolant Drain.
Refer to “CHANGING THE COOLANT” on
page 3-10.
Seat Refer to “GENERAL CHASSIS” on page 5-1.
Side cover (left/right) Refer to “GENERAL CHASSIS” on page 5-1.
Air scoop (left / right) Refer to “GENERAL CHASSIS” on page 5-1.
Fuel tank Refer to “FUEL TANK” on page 8-1.
Air filter case Refer to “THROTTLE BODY” on page 8-7.
1 Radiator guard 2
2 Radiator hose clamp 8 Loosen.
3 Radiator fan 1
12
13
New
New
New
LS
LS
3
4 58 Nm (0.8 m kgf, 5.8 ft Ibf)T.R.
6
7
8 9
10
11 2
2
2
2
2
2
2
1
1
FUEL TANK
8-1
EAS2GC1338
TIP
This section is intended for those who have basic knowledge and skill concerning the servicing of
Yamaha motorcycles (e.g., Yamaha dealers, serv ice engineers, etc.). Those who have little knowl-
edge and skill concerning servicing are requested not to undertake inspection, adjustment, disas-
sembly, or reassembly only by reference to this manual. It may lead to servicing trouble and
mechanical damage.
EAS2GC1339
FUEL TANK
Removing the fuel tank
OrderPart name Q’tyRemarks
Seat Refer to “GENERAL CHASSIS” on page 5-1.
Side cover (left/right)
Air scoop (left/right)
1 Fuel pump coupler 1 Disconnect.
2 Fuel hose 1 Disconnect.
3Fuel tank 1
4 Fuel pump bracket 1
5 Fuel pump 1
6 Fuel pump gasket 1
7 Fuel sender 1
4(6)
(2)
(2)
(2) (2)2
5
6
3
1
New
4.0 Nm (0.40 m kgf, 2.9 ft Ibf)T.R.
7 Nm (0.7 m kgf, 5.1 ft Ibf)T.R.
7 Nm (0.7 m kgf, 5.1 ft Ibf)T.R.
7 Nm (0.7 m kgf, 5.1 ft Ibf)T.R.
9 Nm (0.9 m kgf, 6.5 ft Ibf)T.R.
4.0 Nm (0.40 m kgf, 2.9 ft Ibf)T.R.
4.0 Nm (0.40 m kgf, 2.9 ft Ibf)T.R.
7
TROUBLESHOOTING
10-1
EAS2GC1406
TROUBLESHOOTING
EAS2GC1407GENERAL INFORMATION
TIP
The following guide for troubleshooting does
not cover all the possible causes of trouble. It
should be helpful, however, as a guide to basic
troubleshooting. Refer to the relative procedure
in this manual for checks, adjustments, and re-
placement of parts.
EAS2GC1408STARTING FAILURES
Engine
1. Cylinder and cylinder head• Loose spark plug
• Loose cylinder head or cylinder
• Damaged cylinder head gasket
• Damaged cylinder gasket
• Worn or damaged cylinder
• Incorrect valve clearance
• Improperly sealed valve
• Incorrect valve-to-valve-seat contact
• Incorrect valve timing
• Faulty valve spring
• Seized valve
2. Piston and piston ring(s) • Improperly installed piston ring
• Damaged, worn or fatigued piston ring
• Seized piston ring
• Seized or damaged piston
3. Air filter • Improperly installed air filter
• Clogged air filter element
4. Crankcase and crankshaft • Improperly assembled crankcase
• Seized crankshaft
Fuel system
1. Fuel tank • Empty fuel tank
• Clogged fuel tank breather hose
• Deteriorated or contaminated fuel
• Clogged or damaged fuel hose
2. Fuel pump
• Faulty fuel pump
3. Throttle body • Deteriorated or contaminated fuel
• Sucked-in air Electrical system
1. Battery
• Discharged battery
• Faulty battery
2. Fuse • Blown, damaged or incorrect fuse
• Improperly installed fuse
3. Spark plug • Incorrect spark plug gap
• Incorrect spark plug heat range
• Fouled spark plug
• Worn or damaged electrode
• Worn or damaged insulator
4. Ignition coil • Cracked or broken ignition coil body
• Broken or shorted primary or secondary coils
5. Ignition system • Faulty ECU
• Faulty crankshaft position sensor
• Broken generator rotor woodruff key
6. Switches and wiring
• Faulty ECU
• Faulty engine stop switch
• Broken or shorted wiring
• Faulty neutral switch
• Improperly grounded circuit
• Loose connections
7. Starting system • Faulty starter motor
• Faulty starter relay
• Faulty starting circuit cut-off relay
• Faulty starter clutch
EAS2GC1409INCORRECT ENGINE IDLING SPEED
Engine
1. Cylinder and cylinder head• Incorrect valve clearance
• Damaged valve train components
2. Air filter • Clogged air filter element
Fuel system
1. Throttle body • Damaged or loose throttle body joint
• Improperly synchronized throttle bodies
• Improper throttle cable free play
• Flooded throttle body