2003 YAMAHA TTR90 fuel filter

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GEN
INFO
CONTROL FUNCTIONS
EC156000
FRONT BRAKE LEVER
The front brake lever 1 is located on the right
handlebar. Pull it toward the handlebar to acti-
vate the front brake.
EC157000
REAR BRAKE PEDAL
The rear brake pedal 1 is located on the right
side of the machine. Press down on the brake
pedal to activate the rear brake.
FUEL COCK
The fuel cock supplies fuel from the tank to
carburetor while filtering the fuel. The fuel cock
has the three positions:
OFF: With the lever in this position, fuel will
not flow. Always return the lever to this
position when the engine is not running.
ON: With the lever in this position, fuel flows
to the carburetor. Normal riding is done
with the lever in this position.
RES: This indicates reserve. If you run out of
fuel while riding, move the lever to this
position. FILL THE TANK AT THE
FIRST OPPORTUNITY. BE SURE TO
SET THE LEVER TO “ON” AFTER
REFUELING.
STARTER LEVER (CHOKE)
When cold, the engine requires a richer air/fuel
mixture for starting. A separate starter circuit,
which is controlled by the starter lever 1, sup-
plies this mixture.
Pull the lever out to open the circuit (for start-
ing) and push the lever in to close the circuit.

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INSP
ADJMAINTENANCE INTERVALS/
PERIODIC MAINTENANCE AND LUBRICATION
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.
PERIODIC MAINTENANCE AND LUBRICATION
Dealer
NoteItem Checks and maintenance jobsInitial Every
10 hours
(1 month)60 hours
(6 months)120 hours
(12 months)
* Fuel lineCheck fuel hoses for cracks or damage.
Replace if necessary.
Spark plugCheck condition.
Clean, regap or replace if necessary.
* ValvesCheck valve clearance.
Adjust if necessary.
Air filter Clean or replace if necessary.
* CarburetorCheck engine idling speed and starter operation.
Adjust if necessary.
Exhaust systemsCheck for leakage.
Retighten if necessary.
Replace gasket if necessary.
Engine oilCheck oil level and vehicle for oil leakage.
Correct if necessary.
Change. (Warm engine before draining.)
ClutchCheck operation.
Adjust or replace cable.
* Front brakeCheck operation.
Adjust brake lever free play and replace brake
shoes if necessary.Every ride
* Rear brakeCheck operation.
Adjust brake pedal free play and replace brake
shoes if necessary.Every ride
* WheelsCheck balance, runout, spoke tightness and for
damage.
Tighten spokes and rebalance, replace if
necessary.
* TiresCheck tread depth and for damage.
Replace if necessary.
Check air pressure.
Correct if necessary.
* Wheel bearingsCheck bearing for looseness or damage.
Replace if necessary.
* SwingarmCheck swingarm pivoting point for play.
Correct if necessary.
Lubricate with lithium soap base grease.
Drive chainCheck chain slack.
Adjust if necessary. Make sure that the rear wheel
is properly aligned.
Clean and lubricate.Every ride
* Steering bearingsCheck bearing play and steering for roughness.
Correct accordingly.
Lubricate with lithium soap base grease every 120
hours.
3

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ENG

ENGINE
CARBURETOR
Extent of removal:
1
Carburetor removal
Extent of removal Order Part name Q’ty Remarks
CARBURETOR REMOVAL
Preparation for removal Fuel tank
1 Clamp (air filter joint) 1 Loosen the screw (air filter joint).
2 Carburetor heater lead 1
3 Air vent hose 1
4 Fuel hose 1
5 Bolt 2
6 Carburetor assembly 1
7 O-ring 1
8 Spacer 1
9 Carburetor top 1
10 Starter plunger assembly 1
1

CARBURETOR

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ENGCYLINDER HEAD
CYLINDER HEAD
Extent of removal:1 Cylinder head removal
Extent of removal Order Part name Q’ty Remarks
CYLINDER HEAD REMOVAL
Preparation for removal Seat, fuel tank and rear fender
Exhaust pipe
Carburetor Refer to “CARBURETOR” section.
Air filter case and starter lever
1 Plug cap/spark plug 1/1
2 Crankshaft end cover/O-ring 1/1
3 Timing plug/O-ring 1/1
4 Camshaft sprocket cover/O-ring 1/1
5 Tappet cover (intake)/O-ring 1/1
6 Tappet cover (exhaust)/O-ring 1/1
7 Camshaft sprocket bolt/washer 1/1
Refer to “REMOVAL POINTS”. 8 Timing chain tensioner 1
9 Gasket 1
1

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ENGCRANKCASE AND CRANKSHAFT
CRANKCASE AND CRANKSHAFT
Extent of removal Order Part name Q’ty Remarks
CRANKCASE SEPARATION
AND CRANKSHAFT REMOVAL
Preparation for removal Seat, fuel tank and rear fender
Exhaust pipe
Air filter case
Carburetor Refer to “CARBURETOR” section.
Drain the engine oil Refer to “ENGINE OIL REPLACEMENT”
section in the CHAPTER 3.
Engine guard and drive sprocket
Engine assembly From the chassis.
Cylinder head Refer to “CYLINDER HEAD” section.
Cylinder and piston Refer to “CYLINDER AND PISTON” sec-
tion.
Clutch housing and clutch carrier Refer to “CLUTCH” section.
Kick axle assembly Refer to “KICK AXLE” section.