transmission YAMAHA TTR90 2007 Owners Manual

1-1
1
SAFETY INFORMATION
EAU41860
Safe riding

Always make pre-operation
checks. Careful checks may help
prevent an accident.


This motorcycle is designed for off-
road use only, therefore, it is illegal
to operate it on public streets,
roads, or highways, even a dirt or
gravel one. Off-road use on public
lands may be illegal. Please check
local regulations before riding.


This motorcycle is designed to car-
ry the operator only. No passen-
gers.


Many accidents involve inexperi-
enced operators.
Make sure that the operator is
qualified and that you only lend
your motorcycle to other quali-
fied operators.
Know your skills and limits.
Staying within your limits may
help you to avoid an accident.


Many accidents have been caused
by error of the motorcycle opera-
tor. A typical error made by the op-
erator is veering wide on a turn
due to EXCESSIVE SPEED or un-dercornering (insufficient lean an-
gle for the speed). Never travel
faster than warranted by condi-
tions.


Ride cautiously in unfamiliar ar-
eas. You may encounter hidden
obstacles that could cause an ac-
cident.


The posture of the operator is im-
portant for proper control. The op-
erator should keep both hands on
the handlebar and both feet on the
operator footrests during operation
to maintain control of the motor-
cycle.


Never ride under the influence of
alcohol or other drugs.


Be sure the transmission is in neu-
tral before starting the engine.
Protective apparel
The majority of fatalities from motor-
cycle accidents are the result of head
injuries. The use of a safety helmet is
the single most critical factor in the pre-
vention or reduction of head injuries.


Always wear an approved helmet.


Wear a face shield or goggles.
Wind in your unprotected eyes
could contribute to an impairment
of vision that could delay seeing a
hazard.


The use of a jacket, heavy boots,
trousers, gloves, etc., is effective in
preventing or reducing abrasions
or lacerations.


Never wear loose-fitting clothes,
otherwise they could catch on the
control levers, footrests, or wheels
and cause injury or an accident.


Never touch the engine or exhaust
system during or after operation.
They become very hot and can
cause burns. Always wear protec-
tive clothing that covers your legs,
ankles, and feet.
Modifications
Modifications made to this motorcycle
not approved by Yamaha, or the re-
moval of original equipment, may ren-
der the motorcycle unsafe for use and
may cause severe personal injury.
Modifications may also make your
motorcycle illegal to use.
U3P281E0.book Page 1 Monday, April 17, 2006 11:26 AM

INSTRUMENT AND CONTROL FUNCTIONS
3-2
3
EAU39850
Shift pedal This motorcycle is equipped with a con-
stant-mesh 3-speed transmission. The
shift pedal is located on the left side of
the engine. Neutral is at the bottom po-
sition.
EAU12890
Brake lever The brake lever is located at the right
handlebar grip. To apply the front
brake, pull the lever toward the handle-
bar grip.
EAU12941
Brake pedal The brake pedal is on the right side of
the motorcycle. To apply the rear
brake, press down on the brake pedal.
1. Shift pedal
1. Brake lever
1. Brake pedal
U3P281E0.book Page 2 Monday, April 17, 2006 11:26 AM

INSTRUMENT AND CONTROL FUNCTIONS
3-8
3
EAU41610
Starting circuit cut-off system
[TT-R90E(W)]The starting circuit cut-off system pre-
vents starting when the transmission is
in gear.
Periodically check the operation of the
starting circuit cut-off system according
to the following procedure.
WARNING
EWA10250
If a malfunction is noted, have a
Yamaha dealer check the system be-fore riding.
U3P281E0.book Page 8 Monday, April 17, 2006 11:26 AM

INSTRUMENT AND CONTROL FUNCTIONS
3-9
3
With the engine turned off:
1. Make sure that the engine stop switch is set to “
”.
2. Turn the key to “ON”.
3. Shift the transmission into gear.
4. Keep the front or rear brake applied.
5. Push the start switch.
Does the engine start?
The neutral switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
6. Shift the transmission into the neutral position.
7. Push the start switch.
Does the engine start?
The neutral switch may be defective.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
YES
NOTE:
a warmed-up engine.
NO
The system is OK. The motorcycle can be ridden.
YES
NO
This check is most reliable if performed with
U3P281E0.book Page 9 Monday, April 17, 2006 11:26 AM

OPERATION AND IMPORTANT RIDING POINTS
5-1
5
EAU41680
WARNING
EWA14620


This model is designed for off-
road use only. Become thor-
oughly familiar with all operat-
ing controls and their functions
before riding. Consult a Yamaha
dealer regarding any control or
function that you do not thor-
oughly understand.


Never start the engine or oper-
ate it in a closed area for any
length of time. Exhaust fumes
are poisonous, and inhaling
them can cause loss of con-
sciousness and death within a
short time. Always make sure
that there is adequate ventila-
tion.


Before starting out, make sure
that the sidestand is up. If the
sidestand is not raised com-
pletely, it could contact the
ground and distract the opera-
tor, resulting in a possible lossof control.
EAU41670
Starting and warming up a
cold engine [TT-R90(W)]1. Turn the fuel cock lever to “ON”.
2. Set the engine stop switch to “”.
3. Shift the transmission into the neu-
tral position.
WARNING
EWA14410


Be sure to shift the transmis-
sion into neutral before starting
the engine.


Never ride with the sidestanddown.
4. Turn the starter (choke) on and
completely close the throttle. (See
page 3-6.)
5. Start the engine by pushing the
kickstarter lever down.
CAUTION:
ECA11130
For maximum engine life, always
warm the engine up before starting
off. Never accelerate hard when theengine is cold!
6. When the engine is warm, turn the
starter (choke) off.
NOTE:The engine is warm when it responds
normally to the throttle with the starter(choke) turned off.
U3P281E0.book Page 1 Monday, April 17, 2006 11:26 AM

OPERATION AND IMPORTANT RIDING POINTS
5-2
5
EAU40090
Starting and warming up a
cold engine [TT-R90E(W)]1. Turn the fuel cock lever to “ON”.
2. Turn the key to “ON” and make
sure that the engine stop switch is
set to “”.
3. Shift the transmission into the neu-
tral position.
WARNING
EWA14410


Be sure to shift the transmis-
sion into neutral before starting
the engine.


Never ride with the sidestanddown.
4. Turn the starter (choke) on and
completely close the throttle. (See
page 3-6.)
5. Start the engine by pushing the
start switch.
6. After starting the engine, move the
starter (choke) back halfway.
CAUTION:
ECA11130
For maximum engine life, always
warm the engine up before starting
off. Never accelerate hard when theengine is cold!
7. When the engine is warm, turn the
starter (choke) off.NOTE:The engine is warm when it responds
normally to the throttle with the starter(choke) turned off.
EAU16640
Starting a warm engine Follow the same procedure as for start-
ing a cold engine with the exception
that the starter (choke) is not required
when the engine is warm.
U3P281E0.book Page 2 Monday, April 17, 2006 11:26 AM

OPERATION AND IMPORTANT RIDING POINTS
5-3
5
EAU39901
Shifting This motorcycle has a 3-speed trans-
mission with a centrifugal, automatic
clutch. Shifting gears lets you control
the amount of engine power available
for starting off, accelerating, climbing
hills, etc.
The gear positions are shown in the il-
lustration.NOTE:To shift the transmission into the neu-
tral position, press the shift pedal down
repeatedly until it reaches the end of itstravel.
CAUTION:
ECA15441


Even with the transmission in
the neutral position, do not
coast for long periods of time
with the engine off, and do not
tow the motorcycle for long dis-
tances. The transmission is
properly lubricated only when
the engine is running. Inade-
quate lubrication may damage
the transmission.


Always release the throttle grip
before changing gears to avoid
damaging the engine, transmis-
sion, and drive train, which are
not designed to withstand the
shock of shifting when the throt-tle grip is open.
EAU39910
To start out and accelerate
1. Close the throttle.
2. Shift into first gear and release the
shift pedal.
CAUTION:
ECA15460
Always close the throttle before
shifting gears, otherwise damage to
the engine and drive train may re-sult.
3. Open the throttle gradually.
4. Once the motorcycle has reached
a speed high enough to change
gears, close the throttle.
5. Shift into second gear and release
the shift pedal.
6. Open the throttle gradually.
7. Follow the same procedure when
shifting to the next higher gear.
EAU16710
To decelerate
1. Close the throttle and apply both
the front and the rear brakes to
slow the motorcycle.
2. Downshift through the gears and
shift the transmission into the neu-
tral position when the motorcycle
is almost completely stopped.
1. Shift pedal
2. Neutral positionU3P281E0.book Page 3 Monday, April 17, 2006 11:26 AM

PERIODIC MAINTENANCE AND MINOR REPAIR
6-18
6
EAU41052
Checking the front and rear
brake shoes The front and rear brake shoes must be
checked for wear at the intervals spec-
ified in the periodic maintenance and
lubrication chart.NOTE:
The wheels must be removed to check
brake shoe lining thickness.

To remove the front wheel: See
page 6-27.


To remove the rear wheel: Seepage 6-28.
FrontRear
If the lining thickness of a brake shoe is
less than 1.5 mm (0.06 in), have a
Yamaha dealer replace the brake
shoes as a set.
NOTE:Be sure to measure the brake lining atthe thinnest portion.
EAU22760
Drive chain slack The drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU22771
To check the drive chain slack
1. Place the motorcycle on the side-
stand.NOTE:When checking and adjusting the drive
chain slack, there should be no weighton the motorcycle.
2. Shift the transmission into the neu-
tral position.
3. Move the rear wheel by pushing
the motorcycle to locate the tight-
est portion of the drive chain, and
then measure the drive chain slack
as shown.
1. Lining thickness
1. Lining thickness
Drive chain slack:
40.0–53.0 mm (1.57–2.09 in)
U3P281E0.book Page 18 Monday, April 17, 2006 11:26 AM

SPECIFICATIONS
8-2
8
Fuel:Recommended fuel:
TT-R90 Regular unleaded gasoline only
(AUT)(BEL)(CAN)(CHE)(DEU)(DNK)(ESP
)(FIN)(FRA)(GBR)(GRC)(IRL)(NLD)(NOR)
(PRT)(SWE)(ZAF)
TT-R90 Unleaded gasoline only
(AUS)(NZL)
TT-R90E Regular unleaded gasoline only
(AUT)(BEL)(CAN)(CHE)(DEU)(DNK)(ESP
)(FIN)(FRA)(GBR)(GRC)(IRL)(NLD)(NOR)
(PRT)(SWE)(ZAF)
TT-R90E Unleaded gasoline only
(AUS)(NZL)
Fuel tank capacity:
4.2 L (1.11 US gal) (0.92 Imp.gal)
Fuel reserve amount:
0.5 L (0.13 US gal) (0.11 Imp.gal)Carburetor:Manufacturer:
MIKUNI
Type × quantity:
VM16SH x 1Spark plug (s):Manufacturer/model:
NGK/CR6HSA
Manufacturer/model:
DENSO/U20FSR-U
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)Clutch:Clutch type:
Wet, multiple-disc and centrifugal
automatic
Transmission:Primary reduction system:
Spur gear
Primary reduction ratio:
67/18 (3.722)
Secondary reduction system:
Chain drive
Secondary reduction ratio:
35/14 (2.500)
Transmission type:
Constant mesh 3-speed
Operation:
Left foot operation
Gear ratio:
1st:
37/13 (2.846)
2nd:
33/19 (1.736)
3rd:
28/23 (1.217)Chassis:Frame type:
Steel tube backbone
Caster angle:
24.83 °
Trail:
56.0 mm (2.20 in)Front tire:Type:
With tube
Size:
2.50-14 4PR
Manufacturer/model:
CHENG SHIN/KNOBBY
Rear tire:Type:
With tube
Size:
3.00-12 4PR
Manufacturer/model:
CHENG SHIN/KNOBBYTire air pressure (measured on cold
tires):
Front:
100 kPa (15 psi) (1.00 kgf/cm²)
Rear:
100 kPa (15 psi) (1.00 kgf/cm²)
Front wheel:Wheel type:
Spoke wheel
Rim size:
14x1.40Rear wheel:Wheel type:
Spoke wheel
Rim size:
12x1.60Front brake:Type:
Drum brake
Operation:
Right hand operationRear brake:Type:
Drum brake
Operation:
Right foot operation
U3P281E0.book Page 2 Monday, April 17, 2006 11:26 AM