Yamaha YZ250 2022, Owner'S Service Manual

Page: 226 / 274

CARBURETOR
7-11
5. Adjust:
•
Idle speed
Refer to “CHECKING THE ENGINE IDLING
SPEED” on page 3-5.
EAM30579
MEASURING AND ADJUSTING THE FUEL
LEVEL
1. Measure:
• Float height “a”
Out of specification

Adjust.
a. Hold the carburetor in an upside down po-
sition.
b. Measure the distance between the mating
surface of the float chamber and top of the
float using a vernier calipers.
TIP
The float arm should be resting on the needle
valve, but not compressing the needle valve.
2. Adjust:
•
Fuel level
a. Check the needle valve seat and needle
valve.
b. If either is worn, replace them as a set.
c. If both are fine, adjust the float level by
slightly bending the float tang “1”.
d. Measure the fuel height again.
e. Repeat steps (c) to (d) until the fuel level is
within specification.
Float height
6.5 mm (0.26 in)
1