Yamaha 2002 YB50, Service Manual

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CARB
CARBURETOR
5-4
4. Check:
• throttle valve
Wear/Damage Change
5. Check:
• throttle valve displacement
Irregular movement/Catches Change
Insert the throttle valve in the body
and check its displacement.
6. Check:
• throttle stop screw
• pilot air screw
• jet needle
• starter plunger
Wear/Damage Change
7. Measure:
• Float height
a
Outside specifications Check valve,
float and valve seat
Steps for measuring the height of the float:
• Assemble the valve, float and axle on the
carburettor body
• Turn the carburettor upside down
• Using a vernier caliper, measure the distance
between the plane of the bowl gasket (wit-
hout the gasket) and the upper part of the
float.
Float height a
15.0 mm ~ 17.0 mm