Yamaha LB50IIAC - Engine Periodic Inspections and Adjustments; Yamaha Carburetor Maintenance

ENGINE
Carburetor
1. Make certain that throttle cable free
play is proper.
2.
Pilot air screw
Turn the air adjusting screw (1) until it is
lightly seated, then back it out 1
(LB50
II AC) or 1-3/4 (LBSO II AC) turns.
This
adjustment can be made with the
engine stopped.
3.
Start the engine and let it warm up.
4. Idle speed screw
Turn throttle stop screw (2) in or out to
achieve smooth engine operation at idle
speed specified in
Carburetor Setting
Table.
NOTE:-----------
The pilot air and idle speed screws are
separate
adjustments but they must be
adjusted at the same time to achieve
optimum operating condition at engine
idle speeds.
5.
Throttle cable
After engine idle speed is set, make
cable free
play adjustment at cable
adjustor near throttle grip. Loosen lock-
nut and turn adjustor until there is 0.5 ,
1.0
mm free play between throttle cable
housing and cable adjustor. Retighten
locknut. Loosen cable
adjustor locknut
(at
top of carburetor) and turn cable
adjustor until there is 1.0 mm free play
in cable "2". Retighten locknut.
Air
cleaner
1. Remove the air cleaner case cap and
element assembly.
1. Pilot air screw
2. Idle speed screw
a. 1.0 mm
b. 0.5 ,..._, 1.0 mm
1. Carburetor
2. Slide
3. Cable 2
-36-
4. Junction block
5. Cable 1
6. Throttle grip