Q: Abe, what can you tell us about the “right side air scoop” on
the XBs? I’ve seen people fit larger ones (near mirror images
of the left side) in an attempt to increase cooling capacity.
It seems the smaller one will allow for an increased air
velocity and potentially more cooling. What’s the deal?
– Ryan, Lightning® XB12Scg owner
A: The intent of the right side air scoop is to get better airflow over
the fuel rail when the fan is on (at low speed). Getting proper
airflow to the fuel rail is important in order to prevent vapor-lock
during extended idle or parade duty in hot ambient temperatures.
It turns out that if this scoop has too big of an opening, the airflow
is not directed to the fuel rail as effectively. In our testing, a right
side air scoop created as a mirror image of the left hurt fuel rail
temperatures at idle.
The left side air scoop was shaped to direct air to the rear cylinder
and is very effective at doing that. During our high-speed, hot-
ambient testing, the front and rear spark-plug base temperatures
are virtually identical, whereas on the old tube-twin bikes there was
a 100 Degree Fahrenheit difference (rear running hotter).
