1
GENERAL INFORMATION
LOCATION OF IMPORTANT LABELS............................................................ 1-1
DESCRIPTION .................................................................................................. 1-4
IDENTIFICATION ............................................................................................. 1-5
VEHICLE IDENTIFICATION NUMBER ...................................................... 1-5
ENGINE SERIAL NUMBER ....................................................................... 1-5
VEHICLE EMISSION CONTROL INFORMATION LABEL......................... 1-5
INCLUDED PARTS .......................................................................................... 1-6
SPARK PLUG WRENCH ........................................................................... 1-6
NIPPLE WRENCH...................................................................................... 1-6
HANDLEBAR PROTECTOR .. .................................................................... 1-6
FUEL HOSE JOINT COVER ...................................................................... 1-6
COUPLER FOR CONNECTING OPTIONAL PART................................... 1-6
IMPORTANT INFORMATION .......................................................................... 1-7
PREPARATION FOR REMOVAL A ND DISASSEMBLY............................ 1-7
REPLACEMENT PARTS............................................................................ 1-7
GASKETS, OIL SEALS AND O-RINGS ..................................................... 1-8
LOCK WASHERS/PLATES AND COTTER PINS ...................................... 1-8
BEARINGS AND OIL SEALS ..................................................................... 1-8
CIRCLIPS ................................................................................................... 1-8
BASIC SERVICE INFORMATION .................................................................... 1-9
ELECTRICAL SYSTEM.......... .................................................................... 1-9
SPECIAL TOOLS ........................................................................................... 1-13
CONTROL FUNCTIONS ................................................................................ 1-18
INDICATOR LIGHTS AND WARNING LIGHTS ....................................... 1-18
ENGINE STOP SWITCH .......................................................................... 1-18
START SWITCH....................................................................................... 1-18
CLUTCH LEVER ................................................................................... ... 1-18
SHIFT PEDAL .......................................................................................... 1-19
KICKSTARTER LEVER.......... .................................................................. 1-19
THROTTLE GRIP ..................................................................................... 1-19
FRONT BRAKE LEVER ........................................................................... 1-19
REAR BRAKE PEDAL.............................................................................. 1-19
SIDESTAND ............................................................................................. 1-20
STARTER KNOB/IDLE SCREW .............................................................. 1-20
FUEL TANK CAP ..................................................................................... 1-20
DESCRIPTION
1-4
EAS2GC1009
DESCRIPTION
TIP
Designs and specifications of the vehicle are subject to change without notice. Therefore, please
note that the descriptions in this manual may be different from those for the vehicle you have pur-
chased.1. Clutch lever 12. Headlight
2. Multi-function display 13. Radiator
3. Front brake lever 14. Coolant drain bolt
4. Throttle grip 15. Rear brake pedal
5. Start switch 16. Air filter
6. Radiator cap 17. Drive chain
7. Fuel tank cap 18. Shift pedal
8. Engine stop switch 19. Oil level check window
9. Taillight 20. Starter knob/idle screw
10. Fuel tank 21. Front fork
11. Kickstarter lever
32
1
8
10
91 112 1376
54
15 14 21 20 19 18 17 16
SPECIAL TOOLS
1-16
Valve guide remover & in-
staller set (ø5.5)
90890-04016
Valve guide remover (5.5
mm)
YM-01122
Valve guide installer (5.5
mm)
YM-04015
Valve guide reamer (5.5 mm)
90890-01196This tool is used to replace
the valve guide.
Valve spring compressor
90890-04019
Valve spring compressor
YM-04019 This tool is used to discon-
nect or connect the valve and
the valve spring.
Spacer (crankshaft installer)
90890-04081
Pot spacer
YM-91044 This tool is used to install the
crankshaft.
Universal clutch holder
90890-04086
Universal clutch holder
YM-91042 This tool is used to hold the
clutch when removing or in-
stalling the clutch boss secur-
ing nut.
Valve lapper
90890-04101
Valve lapping tool
YM-A8998 This tool is used to remove
the valve lifter or lap the
valve.
Tool name/Part number
How to useIllustration
YM-04019
YM-91044
CONTROL FUNCTIONS
1-18
EAS2GC1029
CONTROL FUNCTIONS
EAS2GC1030INDICATOR LIGHTS AND WARNING
LIGHTS
Fuel level warning light “ ”
This warning light comes on when the fuel level
drops below approximately 1.6 L (0.42 US gal,
0.35 Imp.gal). When this occurs, refuel as soon
as possible.
The electrical circuit of the warning light can be
checked by pushing the start switch. The warn-
ing light should come on for a few seconds, and
then go off.
If the warning light does not come on initially
when the start switch is pushed, or if the warn-
ing light remains on, have a Yamaha dealer
check the electrical circuit.
Engine trouble warning light “ ”
This warning light comes on or flashes if a prob-
lem is detected in the electrical circuit monitor-
ing the engine. If this occurs, have a Yamaha
dealer check the vehicle.
The electrical circuit of the warning light can be
checked by pushing the start switch. The warn-
ing light should come on for a few seconds, and
then go off.
If the warning light does not come on initially
when the start switch is pushed, or if the warn-
ing light remains on, have a Yamaha dealer
check the electrical circuit.
EAS2GC1031ENGINE STOP SWITCH
The engine stop switch “1” is located on the left
handlebar. Continue pushing the engine stop
switch till the engine comes to a stop.
After the engine stops, the multi-function dis-
play will go off and the power supply to the ECU
(Electronic Control Unit) will be cut off if the en-
gine stop switch is pushed and held.
TIP
The multi-function display will go off after one
minute if the engine stop switch is not pushed.
EAS2GC1032START SWITCH
The start switch “1” is located on the right han-
dlebar. Push this switch to crank the engine
with the starter.
EAS2GC1033CLUTCH LEVER
The clutch lever “1” is located on the left han-
dlebar. The clutch lever disengages or engag-
es the clutch.
Pull the clutch lever toward the handlebar to
disengage the clutch, and release the lever to
engage the clutch.
1. Engine trouble warning light “ ”
2. Fuel level warning light “ ”
12
STARTING AND BREAK-IN
1-28
EAS2GC1048
STARTING AND BREAK-IN
EAS2GC1049FUEL
Always use the recommended fuel as stated
below. Also, be sure to use new gasoline the
day of a race.
ECA
NOTICE
Use only unleaded gasoline. The use of
leaded gasoline will cause severe damage
to the engine internal parts such as valves,
piston rings, and exhaust system, etc.
TIP
Your Yamaha engine has been designed to use
premium unleaded gasoline with a pump oc-
tane number [(R+M)/2] of 91 or higher, or a re-
search octane number of 95 or higher. If
knocking (or pinging) occurs, use a gasoline of
a different brand.
EWA
WARNING
• For refueling, be sure to stop the engine and use enough care not to spill any fuel.
Also be sure to avoid refueling close to a
fire.
• Refuel after the engine, exhaust pipe, etc.
have cooled off.
Gasohol (For USA and Canada)
There are two types of gasohol: gasohol con-
taining ethanol and that containing methanol.
Gasohol containing ethanol can be used if the
ethanol content does not exceed 10%. Gasohol
containing methanol is not recommended by
Yamaha because it can cause damage to the
fuel system or vehicle performance problems.
EAS2GC1050HANDLING NOTEEWA
WARNING
Never start or run the engine in a closed ar-
ea. The exhaust fumes are poisonous; they
can cause loss of consciousness and death
in a very short time. Always operate the ma-
chine in a well-ventilated area.
ECA
NOTICE
• Unlike a two-stroke engine, this engine cannot be kick started when the throttle is
open because the kickstarter may kick
back. Also, if the throttle is open the air/
fuel mixture may be too lean for the engine
to start.
• Before starting the machine, perform the
checks in the pre-operation check list.
EAS2GC1051AIR FILTER MAINTENANCE
According to “CLEANING THE AIR FILTER
ELEMENT” section in the CHAPTER 3, apply
the Yamaha foam air filter oil or other quality
foam air filter oil to the element. (Excess oil in
the element may adversely affect engine start-
ing.)
EAS2GC1052STARTING A COLD ENGINEECA
NOTICE
For maximum engine life, never accelerate
hard when the engine is cold!
In order for the ignition circuit cut-off system to
enable starting, one of the following conditions
must be met:
• The transmission is in the neutral position.
• The transmission is in gear with the clutch le- ver pulled.
1. Pull the starter knob/idle screw “1” to its full length.
TIP
When the ambient temperature is 15°C (59°F)
or below, use the starter knob/idle screw.
2. Completely close the throttle.
3. Start the engine by pushing the start switch.If the engine fails to start when using the
start switch, release it, wait a few seconds,
and then try again.
Each starting attempt should be as short as
possible to preserve the battery. Do not
crank the engine more than 10 seconds on
any one attempt. If the engine does not start
with the starter motor, try using the kickstart-
er.
Recommended fuel
Premium unleaded gasoline
only
Fuel tank capacity 7.5 L (2.0 US gal, 1.7 lmp.gal)
Fuel reserve amount 2.0 L (0.5 US gal, 0.4 Imp.gal)
1
ENGINE SPECIFICATIONS
2-5
CrankshaftCrank assembly width 61.93–62.00 mm (2.438–2.441 in)
Runout limit 0.030 mm (0.0012 in)
Big end side clearance 0.150–0.450 mm (0.0059–0.0177 in)
BalancerBalancer drive method Gear
ClutchClutch type Wet, multiple-disc
Clutch release method Inner push, cam push
Clutch lever free play 7.0–12.0 mm (0.28–0.47 in)
Friction plate 1 thickness 2.92–3.08 mm (0.115–0.121 in)
Wear limit 2.85 mm (0.112 in)
Plate quantity 3 pcs
Friction plate 2 thickness 2.92–3.08 mm (0.115–0.121 in)
Wear limit 2.85 mm (0.112 in)
Plate quantity 5 pcs
Clutch plate 1 thickness 1.90–2.10 mm (0.075–0.083 in)
Plate quantity 4 pcs
Warpage limit 0.10 mm (0.004 in)
Clutch plate 2 thickness 1.50–1.70 mm (0.059–0.067 in)
Plate quantity 3 pcs
Warpage limit 0.10 mm (0.004 in)
Clutch spring free length 50.00 mm (1.97 in)
Limit 47.50 mm (1.87 in)
Spring quantity 6 pcs
Push rod bending limit 0.10 mm (0.004 in)
TransmissionTransmission type Constant mesh 5-speed
Primary reduction system Spur gear
Primary reduction ratio 2.609 (60/23)
Final drive Chain
Secondary reduction ratio 3.846 (50/13)
Operation Left foot operation
Gear ratio
1st 2.417 (29/12)
2nd 1.733 (26/15)
3rd 1.313 (21/16)
4th 1.050 (21/20)
5th 0.840 (21/25)
Main axle runout limit 0.08 mm (0.0032 in)
Drive axle runout limit 0.08 mm (0.0032 in)
Shifting mechanism
Shift mechanism type Shift drum and guide bar
Shift fork guide bar bending limit 0.050 mm (0.0020 in)
Shift fork thickness 4.85 mm (0.1909 in)
Decompression deviceDevice type Auto decomp
Air filterAir filter element Wet element
Air filter oil grade Yamaha foam air filter oil or other quality foam air filter oil
TIGHTENING TORQUES
2-14
Throttle body joint clamp boltM5 1 3.0 Nm (0.30 m·kgf, 2.2 ft·lbf)
Air filter joint clamp bolt M4 1 3.5 Nm (0.35 m·kgf, 2.5 ft·lbf)
Air filter case bolt M6 3 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Air filter bolt M6 1 2.0 Nm (0.20 m·kgf, 1.4 ft·lbf)
Air filter guide holder screw M5 8 2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
Air filter case cap screw M5 1 2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
Starter knob/Idle screw M12 1 2.1 Nm (0.21 m·kgf, 1.5 ft·lbf)
Throttle cable nut (pull) M10 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Throttle cable nut (return) M10 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Clutch cable adjuster and locknut M6 1 4.0 Nm (0.40 m·kgf, 2.9 ft·lbf)
Clutch cable locknut (engine side) M8 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Exhaust pipe nut M6 3See TIP.*2
Exhaust pipe protector screw M6 4 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Exhaust pipe bracket bolt M8 1 20 Nm (2.0 m·kgf, 14 ft·lbf)
Frame and silencer bolt (front) M8 1 30 Nm (3.0 m·kgf, 22 ft·lbf)
Frame and silencer bolt (rear) M8 1 30 Nm (3.0 m·kgf, 22 ft·lbf)
Exhaust pipe clamp bolt M8 2 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Spark arrester bolt M5 4 9 Nm (0.9 m·kgf, 6.5 ft·lbf)
Muffler cap bolt M5 6 5 Nm (0.5 m·kgf, 3.6 ft·lbf)
Oil nozzle bolt M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Engine oil drain bolt M10 1 20 Nm (2.0 m·kgf, 14 ft·lbf)
Crankcase bolt M6 12 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Clutch cable holder bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Crankshaft end accessing screw M36 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Timing mark accessing screw M14 1 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Drive chain sprocket cover bolt M6 2 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Crankcase bearing cover plate
screw M6 8 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Crankcase bearing cover plate
screw (crankshaft) M8 4 18 Nm (1.8 m·kgf, 13 ft·lbf) Crimp.
Clutch cover bolt M6 7 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Left crankcase cover bolt M6 7 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Right crankcase cover bolt M6 11 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil filter element cover bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Oil level check window bolt M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Kick shaft ratchet wheel guide bolt M6 2 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Kickstarter lever bolt M8 1 33 Nm (3.3 m·kgf, 24 ft·lbf)
ITEM
Thread
size Q’ty TIGHTENING TORQUES Remarks
LT
LT
LT
LT
LT
LT
TIGHTENING TORQUES
2-15
TIP
*1:Cylinder head bolt
First, tighten the cylinder head bolts to 30 Nm (3.0 m·kgf, 22 ft·lbf) in the proper tightening sequence
and remove them. Retighten the cylinder head bolts to 20 Nm (2.0 m·kgf, 14 ft·lbf) in the proper tight-
ening sequence, and then tighten the cylinder head bolts further to reach the specified angle 150° in
the proper tightening sequence.Kickstarter lever boss screw
M6 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Primary drive gear nut M20 1 100 Nm (10 m·kgf, 72 ft·lbf)
Clutch spring bolt M6 6 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Clutch boss nut M20 1 75 Nm (7.5 m·kgf, 54 ft·lbf)
Drive sprocket nut M20 1 75 Nm (7.5 m·kgf, 54 ft·lbf) Use a
lock
washer.
Drive axle oil seal stopper bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Segment M8 1 30 Nm (3.0 m·kgf, 22 ft·lbf)
Shift guide bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Stopper lever bolt M6 1 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Shift pedal bolt M6 1 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Rotor nut M12 1 65 Nm (6.5 m·kgf, 47 ft·lbf)
Stator screw M5 2 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Crankshaft position sensor bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
AC magneto lead holder bolt M5 1 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Damper assembly cover bolt M6 2 10 Nm (1.0 m·kgf, 7.2 ft·lbf)
Starter clutch bolt M6 6 16 Nm (1.6 m·kgf, 12 ft·lbf)
Starter motor bolt M6 1 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Starter motor cover bolt M6 1 12 Nm (1.2 m·kgf, 8.7 ft·lbf)
Coolant temperature sensor M10 1 16 Nm (1.6 m·kgf, 12 ft·lbf)
Neutral switch bolt M5 2 3.5 Nm (0.35 m·kgf, 2.5 ft·lbf)
Intake air temperature sensor screw M5 1 1.5 Nm (0.15 m·kgf, 1.1 ft·lbf)
Rectifier/regulator bolt M6 2 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
ECU bolt M5 2 3.8 Nm (0.38 m·kgf, 2.8 ft·lbf)
Ignition coil bolt M6 2 7 Nm (0.7 m·kgf, 5.1 ft·lbf)
Throttle position sensor screw M5 2 3.4 Nm (0.34 m·kgf, 2.5 ft·lbf)
Intake air pressure sensor screw M6 1 5 Nm (0.5 m·kgf, 3.6 ft·lbf)
ITEM
Thread
size Q’ty TIGHTENING TORQUES Remarks
E
E
LT
LT
LT
LT
LT
LT
LT
LT