Yamaha MX775 - Installing the Cylinder Head Assembly

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ENGINE
CYLINDER HEAD COVERS, CYLINDER HEADS
1. Check:
• Cylinder head combustion chamber
Check the combustion chamber for carbon depos-
its.
Any carbon deposits  Eliminate.
TIP
Be sure not to damage the sealing surface of the cylinder
head.
2. Check:
• Cylinder head
Cracks/damage around the hole of spark plug 
Replace.
3. Measure:
• Cylinder head warpage
TIP
Measure the warpage on the contact surface of the cylin-
der head at six points using the straight edge and feeler
gauge set.
Out of specifications  Resurface or replace.
INSTALLING THE CYLINDER HEAD ASSEMBLY
1. Install:
• Cylinder head assembly #1
• Cylinder head bolts “1” to “5”.
TIP
Tighten the bolts to the specified torque in two steps and in
order from “1” to “5”.
2. Install:
• Cylinder head assembly #2
• Cylinder head bolts “1” to “5”.
TIP
Tighten the bolts to the specified torque in two steps and in
order from “1” to “5”.
Warpage limit:
0.05 mm (0.002 in)
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Cylinder head bolt:
1st: 12 N·m (1.2 kgf·m, 8.7 lb·ft)
2nd: 50 N·m (5.0 kgf·m, 36 lb·ft)
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