Honda GX120 Owner's Manual page 56

TECHNICAL & CONSUMER INFORMATION
Problems That May Affect Emissions
If you are aware of any of the following symptoms, have your engine
inspected and repaired by your servicing dealer.
Hard starting or stalling after starting.
Rough idle.
Misfiring or backfiring under load.
Afterburning (backfiring).
Black exhaust smoke or high fuel consumption.
Replacement Parts
The
emission control systems on your Honda engine were designed,
built, and certified to conform with
EPA and California emission
regulations. We recommend the use of genuine Honda parts
whenever you have maintenance done. These original-design
replacement parts are manufactured to the same standards as the
original parts, so you can be confident of their performance. The use
of replacement parts that are not of the original design and quality
may impair the effectiveness of your emission control system.
A manufacturer of an aftermarket part assumes the responsibility that
the part will not adversely affect emission performance. The
manufacturer or rebuilder of the part must certify that use of the part
will not result in
a failure of the engine to comply
with emission
regulations.
Maintenance
Follow the maintenance schedule on page 23. Remember that this
schedule is based on the assumption that your machine will be used
for its designed purpose. Sustained high-load or high-temperature
operation, or use
in
unusually wet or dusty conditions,
will
require
more frequent service.
53