Yamaha Mt 01 T 2005 Manual

							CYLINDERS AND PISTONS
5-42
EAS24380REMOVING THE PISTONS
The following procedure applies to all of the pis-
tons.
1. Remove:
Piston pin clips “1”
Piston pin “2”
Piston “3”
CAUTION:
ECA13810
Do not use a hammer to drive the piston pin 
out.
NOTE:
Before removing the piston pin clip, cover the 
crankcase opening with a clean rag to prevent 
the piston pin clip from falling into the crank-
case.
For reference during installation, put an identi-
fication mark on each piston crown.
Before removing the piston pin, deburr the pis-
ton pin clip’s groove and the piston’s pin bore 
area. If both areas are deburred and the piston 
pin is still difficult to remove, remove it with the 
piston pin puller set “4”.
2. Remove:
Top ring
2nd ringOil ring
NOTE:
When removing a piston ring, open the end gap 
with your fingers and lift the other side of the ring 
over the piston crown.
EAS24410CHECKING THE CYLINDERS AND PISTONS
The following procedure applies to all of the cyl-
inders and pistons.
1. Check:
Piston wall
Cylinder wall
Vertical scratches → Rebore or replace the 
cylinder, and replace the piston and piston 
rings as a set.
2. Measure:
Piston-to-cylinder clearance



 





 
 



 
 



 
 



 
 



 



a. Measure cylinder bore “C” with the cylinder 
bore gauge.
NOTE:
Measure cylinder bore “C” by taking side-to-side 
and front-to-back measurements of the cylinder. 
Then, find the average of the measurements.
 
Piston pin puller set
90890-01304
Piston pin puller
YU-01304
 
Cylinder
Bore
97.000–97.010 mm (3.8189–
3.8193 in)
Taper limit
0.050 mm (0.0020 in)
Out of round limit
0.050 mm (0.0020 in)
“C” = maximum of D
1–D6
“T” = maximum of D1 or D2 - maximum of D5 
or D
6
“R” = maximum of D1, D3 or D5 - minimum of 
D
2, D4 or D6 
						

							CYLINDERS AND PISTONS
5-43
b. If out of specification, rebore or replace the 
cylinder, and replace the piston and piston 
rings as a set.
c. Measure piston skirt diameter D “a” with the 
micrometer.
d. If out of specification, replace the piston and 
piston rings as a set.
e. Calculate the piston-to-cylinder clearance 
with the following formula.
f. If out of specification, rebore or replace the 
cylinder, and replace the piston and piston 
rings as a set.
        
EAS24430CHECKING THE PISTON RINGS
1. Measure:
Piston ring side clearance
Out of specification → Replace the piston 
and piston rings as a set.
NOTE:
Before measuring the piston ring side clearance, 
eliminate any carbon deposits from the piston 
ring grooves and piston rings.
2. Install:
Piston ring
(into the cylinder)
NOTE:
Level the piston ring into the cylinder with the 
piston crown.
 
Piston
Diameter D
96.960–96.975 mm (3.8173–
3.8179 in)
b. 10 mm (0.39 in) from the bottom edge of the 
piston
Piston-to-cylinder clearance =
Cylinder bore “C” -
Piston skirt diameter “D”
 
Piston-to-cylinder clearance
0.025–0.050 mm (0.0010–0.0020 
in)
Limit
0.15 mm (0.0059 in)
 
Piston ring
Top ring
Ring side clearance
0.030–0.080 mm (0.0012–
0.0032 in)
Limit
0.120 mm (0.0047 in)
2nd ring
Ring side clearance
0.030–0.070 mm (0.0012–
0.0028 in)
Limit
0.12 mm (0.0047 in)
a. 10 mm (0.39 in) 
						

							CYLINDERS AND PISTONS
5-44
3. Measure:
Piston ring end gap
Out of specification → Replace the piston 
ring.
NOTE:
The oil ring expander spacer’s end gap cannot 
be measured. If the oil ring rail’s gap is exces-
sive, replace all three piston rings.
EAS24440
CHECKING THE PISTON PINS
The following procedure applies to all of the pis-
ton pins.
1. Check:
Piston pin
Blue discoloration/grooves → Replace the 
piston pin and then check the lubrication sys-
tem.
2. Measure:
Piston pin outside diameter “a”
Out of specification → Replace the piston pin.3. Measure:
Piston pin bore diameter “b”
Out of specification → Replace the piston.
4. Calculate:
Piston-pin-to-piston-pin-bore clearance
Out of specification → Replace the piston pin 
and piston as a set.
EAS24460
INSTALLING THE PISTONS AND 
CYLINDERS
The following procedure applies to all of the pis-
tons and cylinders.
1. Install:
Top ring “1”
2nd ring “2”
Lower oil ring rail “3”
Upper oil ring rail “4”
Oil ring expander “5”
NOTE:
Be sure to install the piston rings so that the 
manufacturer’s marks or numbers face up.
 
Piston ring
Top ring
End gap (installed)
0.30–0.50 mm (0.01–0.02 in)
Limit
0.70 mm (0.0276 in)
2nd ring
End gap (installed)
0.30–0.45 mm (0.01–0.02 in)
Limit
0.80 mm (0.0315 in)
Oil ring
End gap (installed)
0.20–0.70 mm (0.01–0.03 in)
 
Piston pin outside diameter
21.991–22.000 mm (0.8658–
0.8661 in)
Limit
21.971 mm (0.8650 in)
 
Piston pin bore inside diameter
22.004–22.015 mm (0.8663–
0.8667 in)
Limit
22.045 mm (0.8679 in)
Piston-pin-to-piston-pin-bore clearance =
Piston pin bore diameter “b” -
Piston pin outside diameter “a”
 
Piston-pin-to-piston-pin-bore 
clearance
0.004–0.024 mm (0.00016–
0.00094 in)
Limit
0.074 mm (0.00291 in) 
						

							CYLINDERS AND PISTONS
5-45
2. Install:
Piston “1”
Piston pin “2”
Piston pin clips “3” 
NOTE:
Apply engine oil onto the piston pin.
Make sure the arrow mark “a” on the piston fac-
es towards the front of the vehicle.
Before installing the piston pin clip, cover the 
crankcase opening with a clean rag to prevent 
the clip from falling into the crankcase.
Reinstall each piston into its original cylinder 
(numbering order starting from the left: #1 to 
#2).
3. Lubricate:
Piston
Piston rings
Cylinder
(with the recommended lubricant)
4. Offset:
Piston ring end gaps5. Install:
Cylinder “1”
NOTE:
While compressing the piston rings with one 
hand, install the cylinder with the other hand.
 
Recommended lubricant
Engine oil
New
a. Top ring
b. Upper oil ring rail
c. Oil ring expander
d. Lower oil ring rail
e. 2nd ring
A. forward
90 ˚
90 ˚
45 ˚
a.c  b d.e
A
1 
						

							CLUTCH
5-46
EAS25060
CLUTCH
Removing the clutch cover
Order Job/Parts to remove Q’ty Remarks
Engine oilDrain.
Refer to “CHANGING THE ENGINE OIL” on 
page 3-11.
Battery box/Air ductRefer to “GENERAL CHASSIS” on page 
4-1.
Oil tank/Shift rod Refer to “ENGINE REMOVAL” on page 5-1.
1 Crankshaft position sensor coupler 1 Disconnect.
2 Shift arm 1
3 Oil tank bracket 1
4 Clutch cover 1
5 Clutch cover gasket 1
6 Dowel pin 2
For installation, reverse the removal 
procedure.
T R..10 Nm (1.0 m • 
kg, 7.2 ft • Ib)
T R..10 Nm (1.0 m • 
kg, 7.2 ft • Ib)
(10)(5)
2
3 6
4 5 61
New 
						

							CLUTCH
5-47
Removing the crankshaft position sensor
Order Job/Parts to remove Q’ty Remarks
1 Oil seal 1
2 Bearing 1
3 Crankshaft position sensor lead holder 3
4 Crankshaft position sensor 1
For installation, reverse the removal 
procedure.
2
13
3
3
4
LTLT
LT
LTLT
LTLT
LS
T R..10 Nm (1.0 m • 
kg, 7.2 ft • Ib)
New 
						

							CLUTCH
5-48
Removing the clutch
Order Job/Parts to remove Q’ty Remarks
1 Clutch spring plate retainer 1
2 Clutch spring plate 1
3 Clutch spring plate seat 1
4 Pressure plate 1
5 Short clutch push rod 1
6 Friction plate 1 9
7 Clutch plate 8
8 Conical spring washer 1
9 Wire circlip 1
10 Clutch plate 1
11 Friction plate 2 1
12 Clutch damper spring 1
13 Clutch damper spring seat 1
14 Clutch boss 1
15 Thrust washer 1 1
16 Bearing 1
17 Clutch housing 1
LS
LS
New
New
New
E
T R..100 Nm (10.0 m • 
kg, 72 ft • lb)
LT
New
T R..125 Nm (12.5 m • 
kg, 90 ft • lb)
E
E
76
18 19
2024 25
23
22
2117
16
15
14
13
12
11
109
8
1 2 3 45 26 27 2829
(6)
T R..8 Nm (0.8 m • 
kg, 5.8 ft • Ib) 
						

							CLUTCH
5-49
18 Washer 1
19 Circlip 1
20 Oil pump drive gear 1
21 Dowel pin 1
22 Collar 1
23 Thrust washer 2 1
24 Ball 1
25 Long clutch push rod 1
26 Spacer 1
27 Crankshaft position sensor rotor 1
28 Primary drive gear 1
29 Straight key 1
For installation, reverse the removal 
procedure.
Removing the clutch
Order Job/Parts to remove Q’ty Remarks
LS
LS
New
New
New
E
T R..100 Nm (10.0 m • 
kg, 72 ft • lb)
LT
New
T R..125 Nm (12.5 m • 
kg, 90 ft • lb)
E
E
76
18 19
2024 25
23
22
2117
16
15
14
13
12
11
109
8
1 2 3 45 26 27 2829
(6)
T R..8 Nm (0.8 m • 
kg, 5.8 ft • Ib) 
						

							CLUTCH
5-50
Removing the clutch master cylinder
Order Job/Parts to remove Q’ty Remarks
Clutch fluidDrain.
Refer to “BLEEDING THE HYDRAULIC 
CLUTCH SYSTEM” on page 3-14.
1 Clutch fluid reservoir cap holder 1
2 Clutch fluid reservoir cap 1
3 Clutch fluid reservoir diaphragm holder 1
4 Clutch fluid reservoir diaphragm 1
5 Clutch fluid reservoir 1
6 Clutch fluid reservoir hose 1
7 Left rearview mirror 1
8 Clutch fluid reservoir bracket 1
9 Clutch lever 1
10 Bushing 1
11 Clutch switch coupler 1 Disconnect.
12 Clutch switch 1
13 Clutch hose union bolt 1
14 Copper washer 2
15 Clutch hose 1
T R..13 Nm (1.3 m • 
kg, 9.4 ft • Ib)
T R..14 Nm (1.4 m • 
kg, 10 ft • Ib)
T R..30 Nm (3.0 m • 
kg, 22 ft • Ib)
LS
LS
New
7
8 1
2
3
4
5 6
9 10
11
12 17 1516 13
14 
						

							CLUTCH
5-51
16 Clutch master cylinder holder 1
17 Clutch master cylinder 1
For installation, reverse the removal 
procedure.
Removing the clutch master cylinder
Order Job/Parts to remove Q’ty Remarks
T R..13 Nm (1.3 m • 
kg, 9.4 ft • Ib)
T R..14 Nm (1.4 m • 
kg, 10 ft • Ib)
T R..30 Nm (3.0 m • 
kg, 22 ft • Ib)
LS
LS
New
7
8 1
2
3
4
5 6
9 10
11
12 17 1516 13
14