Yamaha MT-09 2021 - Page 304

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CONNECTING RODS AND PISTONS
4. Install:
• Piston “1”
(onto the respective connecting rod “2”)
• Piston pin “3”
• Piston pin clip “4”
TIP
• Apply engine oil onto the piston pin.
• Make sure that the “Y” mark “a” on the connect-
ing rod faces left when the punch mark “b” on
the piston is pointing up as shown.
• Make sure that the clip ends “c” are positioned
away from the cutout “d” in the piston as shown
in the illustration.
• Reinstall each piston into its original cylinder.
5. Lubricate:
•Piston
• Piston ring
• Cylinder
(with the recommended lubricant)
6. Offset:
• Piston ring end gap
7. Lubricate:
• Crankshaft pin
• Connecting rod big end bearing inner surface
(with the recommended lubricant)
8. Install:
• Piston assembly “1”
(into the cylinder “2” and onto the crankshaft
pin)
NOTICE
ECA21490
If the projection “a” of the piston installing
tool damages, you cannot use it. Please han-
dle with care.
TIP
Fit the projection “a” of the piston installing tool
“3” and blunt-edged part “b” of the cylinder, fix
the position of the piston installing tool, and then
push the piston up to the cylinder.
Recommended lubricant
Engine oil
New
1
b
3
a
2
4
4
New
New
G089013
4
d
c
New
a. Top ring
b. 2nd ring
c. Upper oil ring rail
d. Oil ring expander
e. Lower oil ring rail
A. Exhaust side
Recommended lubricant
Engine oil
Piston installing tool
90890-04161
Piston installing tool
YM-04161
c
a,d
90˚
90˚
45˚
b,e