Yamaha TT-R90 Manuel D'atelier Du Proprietaire page 246

CLUTCH
EC484600
Clutch plate
1. Measure:
Clutch plate warpage
G
Out of specification → Replace clutch
plate as a set.
Use a surface plate 1 and thickness
gauge 2.
Warp limit:
0.2 mm (0.008 in)
EC484400
Clutch spring
1. Measure:
Clutch spring free length a
G
Out of specification → Replace springs
as a set.
Clutch spring free length
Standard
26.2 mm
(1.03 in)
Push rod
1. Measure:
Push rod #2 bend
G
Out of specification → Replace.
Bending limit:
0.5 mm (0.02 in)
Primary clutch
1. Measure:
Primary clutch housing inside diameter
G
Out of specification → Replace.
Primary clutch housing inside
diameter:
105 mm (4.13 in)
<Limit>: 106 mm (4.17 in)
2. Measure:
Clutch shoe groove depth a
G
Out of specification → Replace.
Clutch shoe groove depth:
1.0 ~ 1.3 mm (0.039 ~ 0.051 in)
<Limit>: 0.1 mm (0.004 in)
4 - 31
ENG
Limit
24.2 mm
(0.95 in)