2006 YAMAHA TTR50 fuel

4 - 10
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 assembly and fuel tank Refer to “FRONT FENDER, SEAT
ASSEMBLY AND FUEL TANK ” section.
Muffler Refer to “MUFFLER ” section.
Carburetor Refer to “CARBURETOR ” section.
Front wheel Refer to “FRONT WHEEL AND REAR
WHEEL ” section in the CHAPTER 5.
1 Plug cap/spark plug 1/1
2 Crankshaft end cover 1
3 Timing plug 1
4 Camshaft sprocket cover 1
5 Tappet cover 2
6 Camshaft sprocket bolt 1 Refer to “REMOVAL POINTS ”.
7 Timing chain tensioner cap bolt 1
1

4 - 42
ENGAC MAGNETO AND STARTER CLUTCH
AC MAGNETO AND STARTER CLUTCH
È Stake
Extent of removal: 1 Crankcase cover (left) removal
2 Pickup coil/stator removal
3 Rotor removal
4 Starter clutch/wheel gear removal
Extent of removal Order Part name Q ’ty Remarks
AC MAGNETO AND STATOR
REMOVAL
Preparation for removal Seat assembly Refer to “FRONT FENDER, SEAT
ASSEMBLY AND FUEL TANK ” section.
1 Crankcase cover (left) 1
2 Dowel pin 2
3 Gasket 1
4 AC magneto coupler 2
5 Neutral switch lead 1
6 Pickup coil/stator assembly 1
7 Rotor nut 1 Use special tool.
Refer to “REMOVAL POINTS ”.
8 Rotor 1
9 Woodruff key 1
21
3
4

4 - 47
ENGENGINE REMOVAL
ENGINE REMOVAL
(4)
NewNew
LS
T R..30 Nm (3.0 m • kg, 22 ft • Ib)
T R..30 Nm (3.0 m •
kg, 22 ft • Ib)
T R..30 Nm (3.0 m •
kg, 22 ft • Ib)
T R..30 Nm (3.0 m •
kg, 22 ft • Ib)
T R..48 Nm (4.8 m •
kg, 35 ft • Ib)
T R..7 Nm (0.7 m •
kg, 5.1 ft • Ib)
T R..10 Nm (1.0 m • kg, 7.2 ft • Ib)
(3)
10
4
1 6
2
9
3
11
7
5 8
Extent of removal:
1 Engine removal
Extent of removal Order Part name Q ’ty Remarks
ENGINE REMOVAL
Preparation for removal Hold the machine by placing the suitable stand under the frame.
Seat assembly, fuel tank air filter
case cover and air filter case Refer to
“FRONT FENDER, SEAT
ASSEMBLY AND FUEL TANK ” section.
Carburetor Refer to “CARBURETOR ” section.
Muffler Refer to “MUFFLER ” section.
Spark plug cap
Disconnect the AC magneto cou-
plers.
Disconnect the neutral switch
lead.
Starter motor Refer to “ELECTRIC STARTING SYS-
TEM ” section in the CHAPTER 6.

4 - 51
ENGCRANKCASE AND CRANKSHAFT
CRANKCASE AND CRANKSHAFT
E
T R..10 Nm (1.0 m • kg, 7.2 ft • Ib)
T R..10 Nm (1.0 m •
kg, 7.2 ft • Ib)
LT
4
4 3
4
4
5 6
7
9
8
8
12
5 6
4
Extent of removal Order Part name Q ’ty Remarks
CRANKCASE SEPARATION
AND CRANKSHAFT REMOVAL
Preparation for removal Seat assembly and fuel tank
Exhaust pipe
Air filter case and bottom cover Refer to “FRONT FENDER, SEAT
ASSEMBLY AND FUEL TANK ” section.
Carburetor Refer to “CARBURETOR ” section.
Drain the engine oil. Refer to “ENGINE OIL REPLACEMENT ”
section in the CHAPTER 3.
Drive sprocket Refer to “ENGINE REMOVAL ”.
Cylinder head Refer to “CYLINDER HEAD ” section.
Cylinder and piston Refer to “CYLINDER AND PISTON ” sec-
tion.
Primary driven gear Refer to “CLUTCH ” section.

5 - 17
CHASSWINGARM
EC570000
SWINGARM
Extent of removal:1 Swingarm removal
2 Rear shock absorber removal
Extent of removal Order Part name Q ’ty Remarks
SWINGARM REMOVAL
WARNING
Support the machine securely so
there is no danger of it falling over.
Preparation for removal Hold the machine by placing the
suitable stand under the engine.
Seat assembly Refer to “FRONT FENDER, SEAT
ASSEMBLY AND FUEL TANK ” section
in the CHAPTER 4.
Rear wheel Refer to “FRONT WHEEL AND REAR
WHEEL ” section.
Drive chain
1 Rear shock absorber 1
2 Drive chain guard 1
3 Drive chain support 1
4 Drive chain guide 1
1
2

–+ELEC
6 - 2
IGNITION SYSTEM
EC620000
IGNITION SYSTEM
INSPECTION STEPS
Use the following steps for checking the possibility of the malfunctioning engine being attributable to
ignition system failure and for checking the spark plug which will not spark.
NOTE:
Remove the following parts before inspection.
1) Seat assembly
2) Air scoops (left and right)
3) Fuel tank
Refer to “FRONT FENDER, SEAT ASSEMBLY AND FUEL TANK ” section in the CHAPTER 4.
 Use the following special tools in this inspection.
Opama pet-4000 spark checker:
YM-34487
Ignition checker: 90890-06754Pocket tester:YU-03112-C/90890-03112
Spark gap test Clean or replace
spark plug.
Check entire ignition
system for connection. Repair or replace.
Check main switch. Replace.
Check engine stop switch. Replace.
Check ignition coil. Primary coil Replace. Secondary coil Replace.
Check AC magneto. Pickup coil Replace. Replace CDI unit.
No Spark
OK
OK
OK
OK
OK
Spark
No good
No good
No good
No good
No good
No good

–+ELEC
6 - 6
ELECTRIC STARTING SYSTEM
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.
*4 marked: Refer to “ENGINE STOP SWITCH INSPECTION ” section.
NOTE:
 Remove the following parts before inspection.
1) Seat assembly
2) Air scoops (left and right)
3) Fuel tank
Refer to “FRONT FENDER, SEAT ASSEMBLY AND FUEL TANK ” section in the CHAPTER 4.
 Use 12 V battery in this inspection.
 Use the following special tools in this inspection.
Pocket tester:
YU-03112-C/90890-03112
*1 Check fuse. Replace 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. *4 Check engine stop switch. Replace.
Check starter motor operation. Repair or 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
ELECTRIC STARTING SYSTEM
No good
No good
No good

6 - 10
–+ELEC
STARTER MOTOR
1
3
45 6
8
2
\b
1
1
LS
New
New
T R..10 Nm (1.0 m •
kg, 7.2 ft • Ib)
7
Extent of removal:1 Starter motor disassembly
Extent of removal Order Part name Q ’ty Remarks
STARTER MOTOR REMOVAL
Preparation for removal Drain the engine oil. Refer to “ENGINE OIL REPLACEMENT ”
section in the CHAPTER 3.
Bottom cover Refer to “FRONT FENDER, SEAT
ASSEMBLY AND FUEL TANK ” section
in the CHAPTER 4.
1 Starter motor 1 STARTER MOTOR DISASSEM-
BLY
1 Front bracket 1
2 O-ring 1
3 Brush set 1
4 Washer 1
5 Oil seal 1
6 Bearing 1
1
ELECTRIC STARTING SYSTEM