Honda GX 120 Tech Manual page 5

CARBURETOR
Remove Carburetor:
A. Check for restrictor, if applicable, and placement. Restrictor must be installed between carburetor and carburetor insulator
with stock Honda gasket on each side of restrictor. Only stock Honda insulator gasket between black plastic insulator and
head. Air passageway in insulator will not be altered in anyway. All Junior Honda's must use the blue QMA approved
slotted plate only. Failure to use proper restrictor plate, alteration of restrictor plate, or improper installation of plate in
designated classes is cause for immediate DQ and all applicable suspensions will be applied.
B. Check for any alterations or worn parts that would allow additional air into engine: holes, slots, perforations,
spacers, loose bolts, warped flanges etc.
C. Carburetor identification number: BE 60 B
D. Check carburetor for alterations. Upper choke shaft hole may be sealed with silicone type sealer.
E. Two stock Honda intake gaskets may be used between Carburetor and plastic insulator.
F. Carburetor Bore:
G. Carburetor venturi bore: 0.456" no go. This measurement is best made with a no go gauge but may be made
using a telescoping gauge as a no go.
1. Gasket thickness: 0.025"maximum.
2. Restrictor thickness: 0.0625" maximum. No slotting of holes on any Honda restrictor.
3. Insulator gasket thickness: 0.025" maximum.
4. Novice Restrictor hole size: 0.3125"maximum (red).
5. Junior Restrictor hole size: 0.4375"maximum (blue).
Intake end:
Throttle end: maximum diameter 0.632".
maximum diameter 0.950"
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