Instead of the air-cooling of yore, this engine is air- and oil-cooled, and fed by dual Solex carbs instead of fuel injection. The unit is supported in the kind of round-edged cradle frame one can trace all the way back to the R5 from the 1930s. The block and transmission housing are made of bead-blasted aluminum, contrasting with the hand-polished belt guard and valve covers. An exposed, chrome-plated driveshaft running to the rear hub is the kind of historical touch that should be etched with the phrase, “When Men Were Men.”

Since the R18 concept’s philosophy is leaving out anything superfluous, the only electronics to be found work the starter and the lights. A cantilever spring strut hides beneath the minimalist leather seat. A “U” pattern graces the headlight glass, just as with historic units, but this one goes for LEDs instead of halogen. The staggered wheels – 21 inches in front, 18 inches in back – wear rubber from in BMW Motorrad’s historic tire partner, Metzeler.

The only ornamental item on the bike is the paintwork. The teardrop tank and fork are bathed in black, overlaid with a yellow-gold metallic varnish and white, hand-applied pinstripes. The rider gets some ornament, too, with the smooth horse leather jacket featuring built-in protectors.

This two-wheeled teaser is an “emotional and authentic offer for the large cruiser segment,” meaning that we’re being prepared for a line of production motorcycles from BMW with the 1.8-liter flat-twin. Observers think a bagger, a tourer, and a cruiser are on the way, and a thrust at segments owned by Harley-Davidson. BMW Motorrad will reveal the first of them sometime later this year, perhaps in advance of the EICMA show in November.