Yamaha YZ 2018 Series Owner's Service Manual page 7

EASB29B006
HOW TO USE THIS MANUAL
In this manual, descriptions of installation, removal, disassembly, assembly, check, and adjustment
procedures are laid out with the individual steps in sequential order.
• The manual is divided into chapters and each chapter is divided into sections. The current section
title "1" is shown at the top of each page.
• Sub-section titles "2" appear in smaller print than the section title.
• To help identify parts and clarify procedure steps, there are exploded diagrams "3" at the start of
each removal and disassembly section.
• Numbers "4" are given in the order of the jobs in the exploded diagram. A number indicates a re-
moval or a disassembly step.
• Symbols "5" indicate parts to be lubricated or replaced.
Refer to "SYMBOLS".
• A job instruction chart "6" accompanies the exploded diagram, providing the order of jobs, the
names of parts, the notes in jobs, etc.
• Jobs "7" requiring more information (such as special tools and technical data) are described se-
quentially.
EASB29B238
CLUTCH
Removing the clutch
10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft)
10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft)
4
2
(6)
3
12
13
6
O d r r e P a t r
Engine oil
B a r k e p e d l a
1 C u l c t h c a b e l
2 C u l c t h c o v r e
3 G a k s t e
4 C u l c t h s r p n i g
5 P e r s s u e r p a l e t
6 P u s h o r d 1
7 i C c r p i l
8 W a s h r e
9 B e r a n i g
1 0 B l l a
1 1 P u s h o r d 2
1 2 r F t c i o i n p a l e t 1
1 3 C u l c t h p a l e t
5
CLUTCH
11
5
6 10
4 9
8
7
10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft)
New
(5)
12
New
3
22
15
13
14
13
18
17
16
21
New
20
19
75 N ・ m (7.5 kgf ・ m, 55 lb ・ ft)
n a m e Q ' y t R e m a k r s
Drain.
Refer to "CHANGING THE ENGINE OIL" on
page 3-15.
R f e r e o t E " N G N I E R E M O V A " L
1 i D c s o n n e c . t
1
1
5
1
1
1
1
1
1
1
4
8
5-40
1
EASB29B239
REMOVING THE CLUTCH
1. Remove:
• Clutch boss nut "1"
• Lock washer "2"
• Clutch boss "3"
TIP
• Straighten the lock washer tab.
• While holding the clutch boss with the clutch
holder "4", loosen the clutch boss nut.
Universal clutch holder
90890-04086
Universal clutch holder
YM-91042
1
LT
3
EASB29B240
CHECKING THE FRICTION PLATES
1. Check:
• Friction plate
Damage/wear  Replace the friction plates
as a set.
2. Measure:
• Friction plate thickness
Out of specification  Replace the friction
plates as a set.
TIP
Measure it at four points on the friction plate.
o n p a g e - 5 . 1
Friction plate thickness
2.90–3.10 mm (0.114–0.122 in)
Wear limit
2.85 mm (0.112 in)
EASB29B241
CHECKING THE CLUTCH PLATES
1. Check:
• Clutch plate
Damage  Replace the clutch plates as a
set.
2. Measure:
• Clutch plate warpage
(with a surface plate and thickness gauge
"1")
Out of specification  Replace the clutch
plates as a set.
Warpage limit
0.10 mm (0.004 in)
1
4
EASB29B242
CHECKING THE CLUTCH SPRINGS
1. Check:
• Clutch spring
Damage  Replace the clutch springs as a
set.
2. Measure:
• Clutch spring free length
Out of specification  Replace the clutch
springs as a set.
Clutch spring free length
47.80 mm (1.88 in)
Limit
45.41 mm (1.79 in)
5-43
CLUTCH
2
7