Big wheels keep on turning. The new Harley-Davidson Sportster S rolls on a fat 160/70-17 front tire, which is wider than the rear tire on the Street Bob 114. (Photos by Brian J. Nelson and Kevin Wing)

After being roundly criticized for keeping faithful to its roots at the expense of modernization for too long, Harley-Davidson strikes back with the Sportster S, powered by a version of the liquid-cooled 1,252cc V-Twin in the thoroughly modern and warmly received Pan America adventure bike.

It?s a bold new era for the Sportster, and this all-new S version signals the demise for air-cooled Sportys. Bold, too, is this new bike?s chunky styling, with an ultra-fat front tire leading the way. The high-mount shotgun exhaust is another bold styling element, capped by a tailsection inspired by Harley?s XR750 dirt-trackers.
The liquid-cooled Revolution Max motor in the Sportster S is tightly packaged as a structural member of the chassis. The high-mount exhaust system is cladded with shielding to keep excess heat from riders.

The key element of the Sportster S is its Revolution Max 1250T motor, which is used as a structural element rather than a lump to be placed in an external frame. A steel-trellis steering head section combines with an aluminum mid-frame, which helps enable the new bike to weigh about 60 pounds less than the Sportster Forty-Eight. H-D says the S scales in at 502 pounds with its 3.1-gallon tank filled.

Gone is the beloved Harley potato-potato exhaust n...