Yamaha YZ 2018 Series, Owner'S Service Manual

Page: 7 / 402

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.
CLUTCH
5-40
EASB29B238
CLUTCH
Removing the clutch
s k r a m e R y t ’ Q e m a n t r a P r e d r O
Engine oil
Drain.
Refer to “CHANGING THE ENGINE OIL” on
page 3-15.
. 1 - 5 e g a p n o ” L A V O M E R E N I G N E “ o t r e f e R l a d e p e k a r B
. t c e n n o c s i D 1 e l b a c h c t u l C 1
1 r e v o c h c t u l C 2
1 t e k s a G 3
5 g n i r p s h c t u l C 4
1 e t a l p e r u s s e r P 5
1 1 d o r h s u P 6
1 p il c r i C 7
1 r e h s a W 8
1 g n i r a e B 9
1 ll a B 0 1
1 2 d o r h s u P 1 1
4 1 e t a l p n o i t c i r F 2 1
8 e t a l p h c t u l C 3 1
New
New
New
2
3
4
5
(5)
(6)
7
8
9
6 10
11
12
22
1
15
12
13
13
18
19
20
17
16
14
13
LT
21
10 N
・
m (1.0 kgf
・
m, 7.4 lb
・
ft)
10 N ・ m (1.0 kgf ・ m, 7.4 lb ・ ft)
10 N
・
m (1.0 kgf
・
m, 7.4 lb
・
ft)
75 N
・
m (7.5 kgf
・
m, 55 lb
・
ft)
CLUTCH
5-43
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.
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.
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.
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.
Universal clutch holder
90890-04086
Universal clutch holder
YM-91042
Friction plate thickness
2.90–3.10 mm (0.114–0.122 in)
Wear limit
2.85 mm (0.112 in)
3
4
1
2
Warpage limit
0.10 mm (0.004 in)
Clutch spring free length
47.80 mm (1.88 in)
Limit
45.41 mm (1.79 in)
1
7
3
4
6
2
5