Reed Val Ve Ass Em Bl V; Description - Yamaha LB50IIAC Service Manual

Jet needle type: 3G9/3
Clip position:
3
4. Check throttle valve (slide) for signs of
wear. Insert into carburetor body and
check for free movement. If slide, or
body, is out of round causing slide to
stick, replace.
5. Install throttle valve, throttle valve open-
ing and closing mechanism, and needle
assembly in carburetor mixing
chamber. Tighten mixing chamber top
as tight as possible by hand.
6. Install the mixing chamber top cover
and all overflow and vent tubes. Re-
install carburetor.
Check position and routing of all tubes.
Check tightness of all fittings. Make
sure carburetor is mounted in a level
position.
7. After installation, re-adjust throttle
cable and Autolube pump cable per
directions in Chapter 2.
REED VALVE ASSEMBLY
Description
1. Yamaha has designed a unique stainless
steel reed valve located between the
carburetor and cylinder. The valve
works independently on a demand
basis. There's no mechanical device.
such as a rotary valve or piston skirt to
govern its opening and closing.
2. Construction of reed valve assembly.
a. Valve
The valve is made of special flexible
stainless steel and designed to open and
close the inlet port.
b. Case
The case is made of a die-cast
aluminum alloy.
c. Gasket
Made of heat and oil-resisting rubber,
the gasket is "welded" to the case by
heat.
d. Valve stopper
The valve stopper is made of highly-
durable cold-rolled stainless steel plate,
and controls the movement of the valve.
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