Cobra 2007 CX65 Owner's Manual page 47

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
Cold air
Warm air
Dry air
Very humid air
Low altitude
High altitude
Low barometric pressure
High barometric pressure
NOTE:
• Before making any carburetor jetting changes verify that:
o You are using the proper fuel and oil
o The fuel is fresh and uncontaminated
o The oil and fuel have been mixed in the proper ratio
o The carburetor is clean (no plugged jets)
o The air filter is properly clean and oiled
o The float height is within proper specification (proper measuring technique
is described later in this section)
NOTE:
Perform all jetting changes on a motorcycle that has been warmed up to proper
operating temperature.
The carburetor on your Cobra motorcycle is quite adjustable. Figure 49 shows
Mixture will be
Leaner
Richer
Leaner
Richer
Standard
Richer
Richer
Leaner
45
Required adjustment
Richer
Leaner
Richer
Leaner
None
Leaner
Leaner
Richer