charging YAMAHA TTR90 2003 Owners Manual

CHAPTER 4
ENGINE
CARBURETOR
..........................................4-1
CYLINDER HEAD
......................................4-8
CAMSHAFT AND ROCKER ARMS
........4-13
VALVES AND VALVE SPRINGS
............4-16
CYLINDER AND PISTON
........................4-21
CLUTCH
...................................................4-27
KICK AXLE
..............................................4-33
SHIFT SHAFT
..........................................4-34
OIL PUMP
................................................4-36
CDI MAGNETO
AND STARTER CLUTCH
........................4-39
CRANKCASE AND CRANKSHAFT
........4-43
SHIFT FORK, SHIFT CAM
AND TRANSMISSION
.............................4-46
CHAPTER 5
CHASSIS
FRONT WHEEL AND REAR WHEEL
.......5-1
FRONT FORK
............................................5-6
HANDLEBAR
.............................................5-9
STEERING
...............................................5-10
SWINGARM
.............................................5-11
CHAPTER 6
ELECTRICAL
ELECTRICAL COMPONENTS
AND WIRING DIAGRAM
...........................6-1
IGNITION SYSTEM
....................................6-2
ELECTRIC STARTING SYSTEM
..............6-6
CHARGING SYSTEM
..............................6-14
CARBURETOR HEATING SYSTEM
.......6-16
MAINTENANCE RECORD
......................6-19

SPEC
2 - 14
EC212300
ELECTRICAL
Item Standard Limit
CDI:
Magneto-model/manufacturer F5HN/YAMAHA ----
Source coil resistance (color) 688 ~ 1,032 Ω at 20 ˚C (68 ˚F)
(Brown – Green)----
Pickup coil resistance (color) 248 ~ 372 Ω at 20 ˚C (68 ˚F)
(Red – White)----
CDI unit-model/manufacturer 5HN/YAMAHA ----
Ignition coil:
Model/manufacturer 2JN-00/YAMAHA ----
Minimum spark gap 6 mm (0.24 in) ----
Primary winding resistance 0.18 ~ 0.28 Ω at 20 ˚C (68 ˚F) ----
Secondary winding resistance 6.3 ~ 9.5 kΩ at 20 ˚C (68 ˚F) ----
Spark plug cap:
Type Resin ----
Resistance 10 kΩ at 20 ˚C (68 ˚F) ----
Charging system:
System type CDI magneto ----
Model/manufacturer F5HN/YAMAHA ----
Normal output 14 V/100 W at 5,000 r/min ----
Lighting coil 1 resistance (color) 0.64 ~ 0.96 Ω at 20 ˚C (68 ˚F)
(White – Black)----
Lighting coil 2 resistance (color) 0.52 ~ 0.78 Ω at 20 ˚C (68 ˚F)
(Yellow – Black)----
Rectifier/regulator:
Regulator type Semiconductor short circuit ----
Model/manufacture SH620B-12/SHINDENGEN ----
No-load regulated voltage 14.0 ~ 15.0 V ----
Rectifier capacity 8 A ----
Electric starting system:
Type Constant mesh
Starter motor:
Model/manufacturer 5HN/YAMAHA ----
Operation voltage 12 V ----
Output 0.35 kW ----
Armature coil resistance 0.018 ~ 0.022 Ω at 20 ˚C (68 ˚F) ----
Brush overall length 7 mm (0.28 in) 3.5 mm
(0.14 in)
Brush quantity 2 pcs. ----
Spring force 3.92 ~ 5.88 N
(400 ~ 600 g, 14.1 ~ 21.2 oz)3.92 N
(400g,
14.1 oz)
Commutator diameter 17.6 mm (0.69 in) 16.6 mm
(0.65 in)
Mica undercut (depth) 1.35 mm (0.05 in) ----
MAINTENANCE SPECIFICATIONS

3 - 20
INSP
ADJ
BATTERY INSPECTION AND CHARGING
WARNING
Batteries generate explosive hydrogen gas
and contain electrolyte which is made of
poisonous and highly caustic sulfuric acid.
Therefore, always follow these preventive
measures:
Wear protective eye gear when handling
or working near batteries.
Charge batteries in a well-ventilated area.
Keep batteries away from fire, sparks or
open flames (e.g., welding equipment,
lighted cigarettes).
DO NOT SMOKE when charging or han-
dling batteries.
KEEP BATTERIES AND ELECTROLYTE
OUT OF REACH OF CHILDREN.
Avoid bodily contact with electrolyte as it
can cause severe burns or permanent eye
injury.
FIRST AID IN CASE OF BODILY CONTACT:
EXTERNAL
Skin — Wash with water.
Eyes — Flush with water for 15 minutes
and get immediate medical attention.
INTERNAL
Drink large quantities of water or milk fol-
lowed with milk of magnesia, beaten egg
or vegetable oil. Get immediate medical
attention.
CAUTION:
Charging time, charging amperage and
charging voltage for an MF battery are dif-
ferent from those of conventional batteries.
The MF battery should be charged as
explained in the charging method illustra-
tions. If the battery is overcharged, the
electrolyte level will drop considerably.
Therefore, take special care when charging
the battery.
BATTERY INSPECTION AND CHARGING

3 - 21
INSP
ADJ
BATTERY INSPECTION AND CHARGING
NOTE:
Since MF batteries are sealed, it is not possi-
ble to check the charge state of the battery by
measuring the specific gravity of the electro-
lyte. Therefore, the charge of the battery has
to be checked by measuring the voltage at the
battery terminals.
1. Remove:
Seat
Rear fender
2. Disconnect:
Battery lead coupler 1
(from the battery terminals)
NOTE:
Push down on the tab a, and then remove the
battery lead coupler.
3. Remove:
Battery
1 a
4. Measure:
Battery charge
Measurement steps:
Connect a pocket tester 1 to the battery
terminals.
Tester positive probe →
battery positive terminal
Tester negative probe →
battery negative terminal
NOTE:
The charge state of an MF battery can be
checked by measuring its open-circuit
voltage (i.e., the voltage when the positive
terminal is disconnected).
No charging is necessary when the open-
circuit voltage equals or exceeds 12.8 V.
Check the charge of the battery, as shown
in the charts and the following example.
Example
Open-circuit voltage = 12.0 V
Charging time = 6.5 hours
Charge of the battery = 20 ~ 30%
1

3 - 22
INSP
ADJ
BATTERY INSPECTION AND CHARGING
5. Charge:
Battery
(refer to the appropriate charging
method illustration)
WARNING
Do not quick charge a battery.
CAUTION:
Never remove the MF battery sealing
caps.
Do not use a high-rate battery charger
since it forces a high-amperage current
into the battery quickly and can cause
battery overheating and battery plate
damage.
If it is impossible to regulate the charging
current on the battery charger, be careful
not to overcharge the battery.
When charging a battery, be sure to
remove it from the machine. (If charging
has to be done with the battery mounted
on the machine, disconnect the negative
battery lead from the battery terminal.)
To reduce the chance of sparks, do not
plug in the battery charger until the bat-
tery charger leads are connected to the
battery.
Before removing the battery charger lead
clips from the battery terminals, be sure
to turn off the battery charger.
Make sure the battery charger lead clips
are in full contact with the battery termi-
nal and that they are not shorted. A cor-
roded battery charger lead clip may
generate heat in the contact area and a
weak clip spring may cause sparks.
If the battery becomes hot to the touch at
any time during the charging process,
disconnect the battery charger and let the
battery cool before reconnecting it. Hot
batteries can explode!
As shown in the following illustration, the
open-circuit voltage of an MF battery sta-
bilizes about 30 minutes after charging
has been completed. Therefore, wait 30
minutes after charging is completed
before measuring the open-circuit volt-
age.

3 - 23
INSP
ADJ
BATTERY INSPECTION AND CHARGING
Charging method using a variable voltage charger

3 - 24
INSP
ADJ
BATTERY INSPECTION AND CHARGING
Charging method using a constant voltage charger

–+ELEC
6 - 7
INSPECTION STEPS
If the starter motor will not operate, use the following inspection steps.
*1 marked: Refer to “FUSE INSPECTION” section in the CHAPTER 3.
*2 marked: Refer to “BATTERY INSPECTION AND CHARGING” section in the CHAPTER 3.
*3 marked: Refer to “MAIN SWITCH INSPECTION” section.
NOTE:
Remove the following parts before inspection.
1) Seat
2) Rear fender
3) Fuel tank
Use 12 V battery in this inspection.
Use the following special tools in this inspection.
Pocket tester:
YU-3112-C/90890-03112
*1 Check fuseReplace fuse and
check wire harness.
*2 Check battery Recharge or replace.
Check each coupler and
wire connection.Repair or replace.
*3 Check main switch. Replace.
Check starter motor
operation.Repair or replace.
Check starting circuit
cut-off relay.Replace.
Check starter relay. Replace.
Check neutral switch. Replace.
Check start switch. Replace.
OK
OK
OK
OK
OK
OK
OK
OK
No good
No good
No good
No good
No good
No good
No good
No good
No good
ELECTRIC STARTING SYSTEM

–+ELEC
6 - 14
CHARGING SYSTEM
EC680000
CHARGING SYSTEM
EC681001
INSPECTION STEPS
If the battery is not charged, use the following inspection steps.
*1 marked: Refer to “FUSE INSPECTION” section in the CHAPTER 3.
*2 marked: Refer to “CHECKING AND CHARGING THE BATTERY” section in the CHAPTER 3.
NOTE:
Remove the following parts before inspection.
1) Seat
2) Rear fender
3) Fuel tank
Use the following special tool in this inspection.
Pocket tester:
YU-3112-C/90890-03112Inductive tachometer:
YU-8036-B
Engine tachometer:
90890-03113
*1 Check fuse.Replace fuse and
check wire harness.
*2 Check battery. Recharge or replace.
Check each coupler and
wire connection.Repair or replace.
Check charging voltage.Charging system is
good.
Check CDI magneto. Lighting coil Replace.
Replace rectifier/regulator.
OK
OK
OK
No good
OK
No good
No good
No good
No good
OK

6 - 15
–+ELECCHARGING SYSTEM
EC624000
COUPLERS AND LEADS CONNECTION
INSPECTION
1. Check:
Couplers and leads connection
Rust/dust/looseness/short-circuit →
Repair or replace.
CHARGING VOLTAGE INSPECTION
1. Start the engine.
2. Inspect:
Charging voltage
Out of specification → If no failure is
found in checking the source coil resis-
tance, replace the rectifier/regulator.
Tester (+) lead → Red lead 1
Tester (–) lead → Black lead 2
Charging
voltageTester selector
position
14.0 ~ 15.0 V at
5,000 r/minDCV-20
WB
R
Y/R
12
3. Inspect:
Lighting coil resistance
Out of specification → Replace.
Tester (+) lead → White lead 1
Tester (–) lead → Black lead 2
Lighting coil
resistanceTester selector
position
0.64 ~ 0.96 Ω at
20 ˚C (68 ˚F)Ω × 1
WSb
YB
1
2