Cobra 2009 ECX80 AC, Owner'S Manual

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45
Tuning
Carburetor
Jetting Decisions
Although your Cobra is sent from the factory with the carburetor jetted for optimal
performance, you may find it necessary to adjustment your particular jetting due
to current weather conditions, altitude, fuel variations, and/or engine
modifications.
CAUTION:
Proper jetting is very
important for engine performance and engine life.
Symptoms of improper jetting are listed below.
•
Symptoms of incorrect oil or oil / fuel ratio
o
Poor acceleration
o
Misfire at low engine speeds
o
Excessive smoke
o
Spark plug fouling
o
Excessive black oil dripping from exhaust system
•
Symptoms of too rich a fuel mixture
o
Poor acceleration
o
Engine will not ‘rev’ out, blubbers on top
o
Misfire at low engine speeds
o
Excessive smoke
o
Spark plug fouling
o
Wet, black, or overly dark spark plug (when removed for inspection)
•
Symptoms of too lean a fuel mixture
o
Pinging or rattling
o
Erratic acceleration
o
Same actions as running out of fuel
o
High engine temperature
o
White spark plug (when removed for inspection)
NOTE:
When inspecting the spark plug to evaluate jetting, a properly jetted machine will
produce a spark plug that is dry and light tan in color.
Environmental and altitude related mixture adjustments
Condition Mixture will be Required adjustment
Cold air Leaner Richer
Warm air Richer Leaner
Dry air Leaner Richer