2003 YAMAHA TTR125 engine

SPEC
2 - 22
MAINTENANCE SPECIFICATIONS
NOTE:
- marked portion shall be checked for torque tightening after break-in or before each ride.Part to be tightened Thread size Q’tyTightening torque
Nm m•kg ft•lb
Bead stopper M8 × 1.25 1 3 0.3 2.2
Driven sprocket (nut) M10 × 1.25 4 43 4.3 31
Driven sprocket (stud) M10 × 1.25 4 30 3.0 22
Sidestand mounting (nut) M10 × 1.25 1 44 4.4 32
Engine mounting:
Engine bracket (front) and frame M8 × 1.25 2 40 4.0 29
Engine bracket (front) and engine M8 × 1.25 2 40 4.0 29
Engine bracket (upper) and frame M8 × 1.25 2 40 4.0 29
Engine bracket (upper) and cylinder head M8 × 1.25 1 40 4.0 29
Engine and frame (rear) M8 × 1.25 2 40 4.0 29
Pivot shaft and nut M12 × 1.25 1 53 5.3 38
Relay arm and swingarm M12 × 1.25 1 53 5.3 38
Relay arm and connecting arm M10 × 1.25 1 35 3.5 25
Connecting arm and frame M10 × 1.25 1 35 3.5 25
Rear shock absorber assembly and frame M12 × 1.25 1 53 5.3 38
Rear shock absorber assembly and relay arm M10 × 1.25 1 35 3.5 25
Rear shock absorber and locknut (preload) M46 × 1.5 1 42 4.2 30
Drive chain tensioner (upper) M8 × 1.25 1 23 2.3 17
Drive chain tensioner (lower) M6 × 1.0 1 7 0.7 5.1
Drive chain support and swingarm M6 × 1.0 2 7 0.7 5.1
Drive chain guide and swingarm M6 × 1.0 2 7 0.7 5.1
Drive chain guard mounting M6 × 1.0 2 7 0.7 5.1
Fuel tank mounting M6 × 1.0 2 10 1.0 7.2
Fuel tank and fuel cock M6 × 1.0 2 7 0.7 5.1
Fuel tank and fuel tank bracket M6 × 1.0 4 7 0.7 5.1
Front fender mounting M6 × 1.0 4 7 0.7 5.1
Rear fender mounting M6 × 1.0 4 7 0.7 5.1
Flap guard mounting M6 × 1.0 2 4 0.4 2.9
Left side cover mounting M6 × 1.0 2 7 0.7 5.1
Seat mounting M6 × 1.0 2 7 0.7 5.1

2 - 24
SPEC
GENERAL TORQUE SPECIFICATIONS/
DEFINITION OF UNITS
EC220001
GENERAL TORQUE SPECIFICATIONS
This chart specifies torque for standard fasten-
ers with standard I.S.O. pitch threads. Torque
specifications for special components or
assemblies are included in the applicable sec-
tions of this book. To avoid warpage, tighten
multi-fastener assemblies in a crisscross fash-
ion, in progressive stages, until full torque is
reached. Unless otherwise specified, torque
specifications call for clean, dry threads. Com-
ponents should be at room temperature.
A
(Nut)B
(Bolt)TORQUE
SPECIFICATION
Nm m•kg ft•lb
10 mm
12 mm
14 mm
17 mm
19 mm
22 mm6 mm
8 mm
10 mm
12 mm
14 mm
16 mm6
15
30
55
85
1300.6
1.5
3.0
5.5
8.5
134.3
11
22
40
61
94
A: Distance between flats
B: Outside thread diameter
EC230000
DEFINITION OF UNITS
Unit Read Definition Measure
mm
cmmillimeter
centimeter10
-3 meter
10-2 meterLength
Length
kg kilogram 10
3 gram Weight
N Newton 1 kg
× m/sec2Force
Nm
m • kgNewton meter
Meter kilogramN
× m
m
× kgTorque
Torque
Pa Pascal N/m
2Pressure
N/mm Newton per millimeter N/mm Spring rate
L
cm
3Liter
Cubic centimeter—
—Volume or capacity
Volume or capacity
r/min Revolution per minute—Engine speed

2 - 25
SPECCABLE ROUTING DIAGRAM
EC240000
CABLE ROUTING DIAGRAM
1Fuel tank breather hose
2CDI unit
3CDI unit band
4Clamp
5CDI magneto lead
6Air vent hose
7Wire harness
8Engine stop switch lead
9Cable guide
0Brake cable
(Brake hose for the
TT-R125LW)
ABrake cable holder
(Brake hose holder for the
TT-R125LW)ÅFit the CDI unit band over the CDI unit bracket till it stops.
ıClamp the ignition coil lead.
ÇClamp the wire harness coupler.
ÎClamp the CDI magneto lead, throttle cable and starter cable.
‰Clamp the CDI magneto lead so that it does not contact the push lever.
ÏPass the air vent hoses between the engine and swingarm.
ÌClamp the wire harness and engine stop switch lead.
ÓPass the brake cable (brake hose for the TT-R125LW) into the cable guide.
ÈClamp the brake cable.
ÔClamp the brake hose between the paint marks.

2 - 26
SPECCABLE ROUTING DIAGRAM
1Air vent hose
2Spark plug lead
3Starter cable
4Throttle cable
5Clutch cable
6Clamp
7Cable guide
8Engine oil breather hose
9Overflow hoseÅAfter clamping the starter cable, push it against the starter plunger.
ıPut the tip of the air vent hose into the main pipe.
ÇInstall the primary coil terminal (orange) to the ignition coil.
ÎFasten the ground lead together with the ignition coil.
‰Pass the clutch cable on the inside of the throttle and starter cable.
ÏClamp the clutch cable with the paint in the cable guide bottom recess.
ÌPass the throttle cable and starter cable into the cable guide.
ÓPass the engine oil breather hose and overflow hose between the right
half of the swingarm and pillar tube.
ÈClamp the engine oil breather hose, overflow hose and air vent hose to
2 clicks.

2 - 27
SPECCABLE ROUTING DIAGRAM
1Engine stop switch lead
2Engine stop switch
3Fuel tank breather hose
4Clamp
5Brake cable
(Brake hose for the TT-R125LW)
6Clutch cable
7Throttle cableÅPass the engine stop switch lead in the middle of the clutch holder.
ıClamp the engine stop switch lead to the handlebar to 3 clicks.
ÇPass the brake cable (brake hose for the TT-R125LW) in front of the
number plate and through the cable guide.
ÎPass the clutch cable in back of the number plate.
‰Insert the fuel tank breather hose into the hole in the starter knob stay
more the 30 mm (1.18 in).
ÏClamp the throttle cable adjuster cover to the handlebar with the clamp
ends downward.

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.
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 element 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.
Check fluid level and leakage. (TT-R125LW only)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 molybdenum disulfide 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.
SidestandCheck operation.
Lubricate and repair if necessary.

3 - 3
INSP
ADJ
PRE-OPERATION INSPECTION AND MAINTENANCE
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation or practice, make sure the machine is in good operating condi-
tion.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
FuelCheck that a fresh gasoline is filled in the fuel tank. Check the
fuel line for leakage.P.1-12
Engine oilCheck that the oil level is correct. Check the crankcase for leak-
age.P.3-7 ~ 10
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-4
Throttle grip/housingCheck that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.P.3-4 ~ 5
BrakesCheck the play of front and rear brake and effect of front and
rear brake.
Check fluid level and leakage. (TT-R125LW only)P.3-15 ~ 20
Drive chainCheck chain slack and alignment. Check that the chain is lubri-
cated properly.P.3-21 ~ 22
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-24 ~ 25
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-25 ~ 27
Front forks and rear shock
absorber assemblyCheck that they operate smoothly and there is no oil leakage. P.3-23 ~ 24
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.—
Muffler Check that the muffler is tightly mounted and has no cracks. P.4-2
Sprocket Check that the driven sprocket tightening nut is not loose. P.3-20
Lubrication Check for smooth operation. Lubricate if necessary. P.3-28
Bolts and nuts Check the chassis and engine for loose bolts and nuts.—
Lead connectorsCheck that the CDI magneto, CDI unit, and ignition coil are con-
nected tightly.P.1-5

3 - 4
INSP
ADJENGINE/CLUTCH ADJUSTMENT/
THROTTLE CABLE ADJUSTMENT
EC350000
ENGINE
CLUTCH ADJUSTMENT
1. Check:
Clutch lever free play a
Out of specification → Adjust.
Clutch lever free play a:
10 ~ 15 mm (0.39 ~ 0.59 in)
2. Adjust:
Clutch lever free play
NOTE:
Make minute adjustment on the lever side.
After adjustment, check proper operation of
clutch lever. Clutch lever free play adjustment steps:
Loosen the locknut 1.
Turn the adjuster 2 until free play a is
within the specified limits.
Tighten the locknut.
EC35A001
THROTTLE CABLE ADJUSTMENT
1. Check:
Throttle grip free play a
Out of specification → Adjust.
Throttle grip free play a:
3 ~ 5 mm (0.12 ~ 0.20 in)
2. Adjust:
Throttle grip free play
Throttle grip free play adjustment steps:
Loosen the locknut 1.
Turn the adjuster 2 until the specified free
play is obtained.
Tighten the locknut.