Acronym Definition
XL Extra Large
XL Excel (Microsoft)
XL Extra Long
XL Xl Capital Ltd.
XL Ixelles (commune of Brussels, Belgium)
XL Excess of Loss (insurance)
XL Excellence in Leadership Program (EPA)
XL Harley-Davidson Sportster model

 

You forgot-
XL.....EXTRA LAME!!!

 

Original definition in Harley lexicon XL meant "eXperimental Lightweight." Now it pretty much denotes Sportster models as a prefix along with the inclusion of the engine size and suffix for the model type (S,C,R,L,N).

 

To bad, they aren't light.

 

The first letter of the designation indicates the engine series sport or special construction. The second letter L designated high compression.

 

Bingo! We have a winner!

 

or maybe XL stands for : cross legged, your not gettin any tonight !!!!!!!!!

 

According to Wille G from an article in the Jan issue of a popular bikers Magazine

 

I don't think the XL combined ever meant anything. Rather, the X, which was originally used by Harley for designating Special Construction from 1918 through 1922 and then again on some military units around 1944 simply became the model designator in 1957 when the K model was replaced by the Sportster. The L designation in the second character began as a designator for high compression units. Later models would also use the C designator XLC for competition and H for high compression 9:1 or high powered and some would even say it meant hot.

 

If I'm not mistaken, the XL in 1957 only had a compression ratio of 7.5:1.

In 1958 they introduced the XLC (Competition) and XLCH (California Hot) models which had higher compression, bigger valves, domed pistons, etc......

Even so these higher performance XLC and XLCH models weren't 'speed demons' and published articles showed quearter mile times in the 14.5 to 15.0 second range.