The Harley-Davidson Sportster ’s roots go all the way back to the 1952 flathead-powered K-Model. Harley went to an over-head cam engine in ’57 and slapped the XL designator on the family.

Conventional wisdom holds that the letters come from “eXperimental modeL” because that’s exactly what it was at the time, a market study to see how well a smaller, sportier product would perform in a market dominated by larger and heavier cruiser -style bikes. I suppose you could call the “eXperiment” a success given that we are still seeing XL models here in 2016.

One problem you run into with such a long-lived family is that you can run out of new things to do to keep it fresh, and the 2017 Sportster 1200 Custom demonstrates that Harley isn’t quite out of ideas yet, even if it borrows ideas from its own customer base.
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