Yamaha 15C Service Manual - Spec
2-3
MAINTENANCE SPECIFICATIONS
SPEC
MAINTENANCE SPECIFICATIONS
ENGINE
Item
Unit
Model
9.9C
15C
Cylinder head
Warpage limit
mm (in)
0.10 (0.0039)
Cylinder
Bore size
mm (in)
56.000–56.020 (2.2047-2.2055)
Wear limit
mm (in)
56.1 (2.21)
Taper limit
mm (in)
0.08 (0.0032)
Out-of-round limit
mm (in)
0.05 (0.0020)
Piston
Piston diameter (D)
mm (in)
55.940–55.985 (2.2024–2.2041)
Measuring point (H)
mm (in)
10.0 (0.39)
Piston-to-cylinder clearance
mm (in)
0.035–0.040 (0.0014–0.0016)
Wear limit
0.09
Piston pin boss bore
mm (in)
14.004–14.015 (0.5513–0.5518)
Piston pin
Outside diameter
mm (in)
13.996–14.000 (0.5510–0.5512)
Piston rings
Top ring
Keystone
Dimension B
mm (in)
1.98–2.00 (0.0780–0.0787)
Dimension T
mm (in)
2.40–2.60 (0.0945–0.1024)
End gap
mm (in)
0.15–0.35 (0.0059–0.0138)
Side clearance
mm (in)
0.02–0.06 (0.0008–0.0024)
2nd ring
Barrel
Dimension B
mm (in)
1.96–1.98 (0.0772–0.0780)
Dimension T
mm (in)
2.40–2.60 (0.0945–0.1024)
End gap
mm (in)
0.15–0.35 (0.0059–0.0138)
Side clearance
mm (in)
0.04–0.08 (0.0016–0.0032)
Reed valve
Valve stopper height
mm (in)
0.6–0.7 (0.02–0.03)
5.9–6.1 (0.23–0.24)
Valve vending limit
mm (in)
0.200 (0.0079)
Connecting rod
Small end inside diameter
mm (in)
18.000–18.011 (0.7087–0.7091)
Big end inside diameter
mm (in)
28.039–28.052 (1.1039–1.1044)
Crankshaft
Crank width
(A)
mm (in)
46.90–46.95 (1.85–1.85)
(B)
mm (in)
25.90–26.10 (1.02–1.03)
Runout limit
(D)
mm (in)
0.03 (0.0012)
Big end side clearance (E)
mm (in)
0.300–0.800 (0.0118–0.0315)
Maximum small end axial play (F)
mm (in)
2.0 (0.08)
Chapter2 03.11.14 20:06 Page 3