Checking The Reed Valves; Installing The Intake Manifold - Yamaha 25BMH Service Manual

POWR
INTAKE MANIFOLD AND REED VALVES

CHECKING THE REED VALVES

1. Check:
• Reed valve
Cracks/damage → Replace.
2. Measure:
• Valve bending
Out of specification → Replace.
Valve bending limit
0.2 mm (0.0079 in)
3. Measure:
• Valve stopper height
Out of specification → Replace.
Valve stopper height
25B:
1.7 - 2.3 mm (0.067 - 0.091 in)
30H:
4.5 - 5.1 mm (0.177 - 0.201 in)

INSTALLING THE INTAKE MANIFOLD

Install:
• Intake manifold
NOTE:
• Tighten the intake manifold mounting
bolts in two steps of torque.
• Apply LOCTITE
Intake manifold mounting bolt
1st: 4 N
2nd: 8 N
5-20
1
a
b
®
No.572 on the bolts.
m (0.4 kgf m, 3.0 ft
• •
m (0.8 kgf m, 5.9 ft
• •
E
lb)
•
lb)
•