Yamaha Mt 01 T 2005 Manual

							ELECTRIC STARTER
5-72
EAS24790CHECKING THE STARTER MOTOR
1. Check:
Commutator
Dirt → Clean with 600 grit sandpaper.
2. Measure:
Commutator diameter “a”
Out of specification → Replace the starter 
motor.
3. Measure:
Mica undercut “a”
Out of specification → Scrape the mica to the 
proper measurement with a hacksaw blade 
that has been grounded to fit the commutator.
NOTE:
The mica of the commutator must be undercut to 
ensure proper operation of the commutator.
4. Measure:
Armature assembly resistances (commutator 
and insulation)
Out of specification → Replace the starter 
motor.



 





 
 



 
 



 
 



 
 



 



a. Measure the armature assembly resistances 
with the pocket tester.
b. If any resistance is out of specification, re-
place the starter motor.
          
5. Measure:
Brush length “a”
Out of specification → Replace the brushes 
as a set.
6. Measure:
Brush spring force
Out of specification → Replace the brush 
springs as a set.
 
Limit
27.5 mm (1.08 in)
 
Mica undercut (depth)
1.50 mm (0.06 in)
 
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
 
Armature coil
Commutator resistance “1”
0.0081–0.0099 Ω at 20°C (68°F)
Insulation resistance “2”
Above 1 MΩ at 20°C (68°F)
 
Limit
5.00 mm (0.20 in)
 
Brush spring force
7.36–11.04 N (26.49–39.74 oz) 
(750–1126 gf) 
						

							ELECTRIC STARTER
5-73
7. Check:
Gear teeth
Damage/wear → Replace the gear.
8. Check:
Bearing
Oil seal
Damage/wear → Replace the defective 
part(s).
EAS24800ASSEMBLING THE STARTER MOTOR
1. Install:
Brush seat “1”
NOTE:
Align the slot “a” on the brush seat with the tab 
“b” in the starter motor front cover.
2. Install:
Starter motor yoke “1”
NOTE:
Align the tab “a” on the brush holder with the slot 
“b” in the starter motor yoke.3. Install:
Starter motor yoke “1”
Starter motor front cover “2”
Starter motor rear cover “3”
NOTE:
Align the match mark “a” on the starter motor 
yoke with the match mark “b” on the starter mo-
tor rear cover.
b
a
1
1
b
a
3
1
2a
b 
						

							CRANKCASE
5-74
EAS25540
CRANKCASE
Separating the crankcase
Order Job/Parts to remove Q’ty Remarks
Engine Refer to “ENGINE REMOVAL” on page 5-1.
Camshafts Refer to “CAMSHAFTS” on page 5-16.
PistonsRefer to “CYLINDERS AND PISTONS” on 
page 5-41.
Shift shaft Refer to “SHIFT SHAFT” on page 5-64.
Generator rotorRefer to “GENERATOR AND STARTER 
CLUTCH” on page 5-66.
1 Speed sensor 1
2 Oil filter cartridge bracket 1
3 Generator shaft end cover 1
4 Oil delivery pipe 2 1
5 Oil pump driven gear stopper 1
6 Oil pump driven gear 1
7 Left crankcase 1
8 Dowel pin 2
9 Joint pipe 1 
						

							CRANKCASE
5-75
10 Right crankcase 1
For installation, reverse the removal 
procedure.
Separating the crankcase
Order Job/Parts to remove Q’ty Remarks 
						

							CRANKCASE
5-76
Removing the oil baffle plate and bearings
Order Job/Parts to remove Q’ty Remarks
Oil pump Refer to “OIL PUMP” on page 5-81.
Crankshaft Refer to “CRANKSHAFT” on page 5-86.
Transmission Refer to “TRANSMISSION” on page 5-92.
1 Oil baffle plate 1
2 Bearing retainer 1
3 Bearing retainer 1
4 Oil seal 1
5 Bearing 4
For installation, reverse the removal 
procedure. 
						

							CRANKCASE
5-77
EAS25570DISASSEMBLING THE CRANKCASE
NOTE:
Loosen the generator shaft bolt before removing 
the generator rotor.
1. Loosen:
Generator shaft bolt “1”
NOTE:
While the holding the generator rotor “2” with the 
primary sheave holder “3”, loosen the generator 
shaft bolt.
2. Remove:
Crankcase bolts
NOTE:
Loosen each bolt 1/4 of a turn at a time, in stag-
es and in a crisscross pattern. After all of the 
bolts are fully loosened, remove them.
Loosen the bolts in decreasing numerical order 
(refer to the numbers in the illustration).
The numbers embossed on the crankcase in-
dicate the crankcase tightening sequence.
M8 × 100 mm bolts: “1”, “2”
M8 × 80 mm bolt: “3”
M6 × 105 mm bolt: “21”
M6 × 85 mm bolt: “9”, “13”M6 × 75 mm bolts: “14”, “15”
M6 × 60 mm bolts: “4”–“7”
M6 × 40 mm bolts: “8”, “10”–“12”, “16”–“20”
3. Turn:
Shift drum segment
NOTE:
Turn the shift drum segment “1” to the position 
shown in the illustration. In this position, the shift 
drum segment’s teeth will not contact the crank-
case during crankcase separation.
4. Remove:
Left crankcase
CAUTION:
EC5YU1016
First check that the shift drum segment’s 
teeth then remove the left crankcase.
 
Sheave holder
90890-01701
Primary clutch holder
YS-01880-A
A. Right crankcase
B. Left crankcase 
						

							CRANKCASE
5-78
Tap on one side of the crankcase with a 
soft-face hammer. Tap only on reinforced 
portions of the crankcase, not on the crank-
case mating surfaces. Work slowly and 
carefully and make sure the crankcase 
halves separate evenly.
EAS25580CHECKING THE CRANKCASE
1. Thoroughly wash the crankcase halves in a 
mild solvent.
2. Thoroughly clean all the gasket surfaces and 
crankcase mating surfaces.
3. Check:
Crankcase
Cracks/damage → Replace.
Oil delivery passages
Obstruction → Blow out with compressed air.
ET5YU1022CHECKING THE BEARINGS AND OIL SEAL
1. Check:
Bearings
Clean and lubricate the bearings, then rotate 
the inner race with your finger.
Rough movement → Replace.
Oil seal
Damage/wear → Replace.
EAS25590
CHECKING THE OIL PIPE
1. Check:
Oil pipe
Damage → Replace.
Obstruction → Wash and blow out with com-
pressed air.
EAS25610
CHECKING THE OIL PUMP DRIVE
1. Check:
Oil pump drive gear
Oil pump driven gear
Chips/pitting/roughness/wear → Replace the 
defective part(s).
ET5YU1023INSTALLING THE BEARING RETAINER
1. Install:
Bearing retainer “1”
NOTE:
Install the bearing retainer “1” with its “OUT” 
mark “a” facing outward.
Apply locking agent (LOCTITE
®) to the threads 
of the bearing retainer bolt.
EAS25690ASSEMBLING THE CRANKCASE
1. Apply:
Sealant
(onto the crankcase mating surfaces)
NOTE:
Do not allow any sealant to come into contact 
with the oil gallery.
2. Install:
Dowel pins “1”
Joint pipe “2”
3. Install:
Left crankcase
(onto the right crankcase)
NOTE:
Turn the shift drum segment “1” to the position 
shown in the illustration. In this position, the 
shift drum segment’s teeth will not contact the 
crankcase during crankcase installation.
 
Yamaha bond No. 1215
90890-85505
OUT
a
1 
						

							CRANKCASE
5-79
Tap lightly on the left crankcase with a soft-
face hammer.
4. Install:
Crankcase bolts (M8)
Crankcase bolts (M6)
NOTE:
Lubricate the bolt threads with engine oil.
Tighten each bolt 1/4 of a turn at a time, in stag-
es and in a crisscross pattern.
Tighten the bolts in numerical order (refer to 
the numbers in the illustration).
M8 × 100 mm bolts: “1”, “2”
M8 × 80 mm bolt: “3”
M6 × 105 mm bolt: “21”
M6 × 85 mm bolts: “9”, “13”
M6 × 75 mm bolts: “14”, “15”
M6 × 60 mm bolts: “4”–“7”
M6 × 40 mm bolts: “8”, “10”–“12”, “16”–“20”5. Apply:
Engine oil
(onto the crankshaft pins bearings and oil de-
livery holes)
6. Check:
Crankshaft and transmission operation
Rough movement → Repair.
7. Install:
Generator shaft bolt “1”
NOTE:
While the holding the generator rotor “2” with the 
primary sheave holder “3”, tighten the generator 
shaft bolt.
T R.. 
Crankcase bolt (M8)
24 Nm (2.4 m·kg, 17 ft·lb)
Crankcase bolt (M6)
10 Nm (1.0 m·kg, 7.2 ft·lb)
A. Right crankcase
B. Left crankcase
T R.. 
Generator shaft bolt
28 Nm (2.8 m·kg, 20 ft·lb)
 
Sheave holder
90890-01701
Primary clutch holder
YS-01880-A 
						

							CRANKCASE
5-80 
						

							OIL PUMP
5-81
EAS24910
OIL PUMP
Removing the oil pump
Order Job/Parts to remove Q’ty Remarks
CrankcaseSeparate.
Refer to “CRANKCASE” on page 5-74.
1 Oil strainer (crankcase) 1
2 Oil pump assembly 1
For installation, reverse the removal 
procedure.