Yamaha RS90K Manuel D'atelier page 472

CYLINDER HEAD
• Tighten the cylinder head bolts further to reach
the specified angle 180° in the proper tightening
sequence as shown.
Cylinder head bolt (M10):
Final:
WARNING
When the bolts are tightened more than the
specified angle, do not loosen the bolt and then
retighten it.
Replace the bolt with a new one and perform
the procedure again.
CAUTION:
• Do not use a torque wrench to tighten the bolt
to the specified angle.
• Tighten the bolt until it is at the specified
angle.
NOTE:
When using a hexagonal bolt, note that the angle
from one corner to another is 60°.
4. Tighten:
• Cylinder head bolts (M6) 1
Cylinder head bolt:
12 Nm (1.2 m · kg, 8.7 ft · lb)
1
5-27
ENG
Specified angle 180°