AD HOC BMW K1100 ‘ALPHA-OMEGA’

BMW’s K-series tourers are an acquired taste in their original state. There’s no denying their rock solid build quality and engineering superiority over their older and decidedly lumpier air cooled R-series cousin but for some reason many prefer the sticky-out cylinders and purer mechanicals. The ‘Flying Brick’ is a far more refined machine and arguably more attractive from an engine layout perspective. Personally, I quite like the teutonic motor with a rocker cover one side and sump on the other.

Packaging this up and creating an aesthetically pleasing retrospective silhouette is a challenge to say the least, one relished by David González of Ad Hoc Café Racers from Barcelona, a chap not known for taking the easier, well trodden path. Some of his previous bikes still look as fresh today as when they were built four years ago.

The angular nineties lines needed to make way for a more traditional café racer so this ’92 K1100 model was stripped right back to the bare essentials. The existing rear triangle on these frames is already well proportioned so David grafted in a rear loop, with subtle kick-up which not only assists with ground clearance but also avoids that slabby-saddle look. A integrated hump in the leather covered seat itself shortens the top-line of the bike’s shape and gives the rider something to push back on when in the prone position. And with these clipons, in-house fabricated rearsets and slammed forks it’ll take all but the tallest of riders not to feel stretched-out and racy.

David has tried to maintain this clean line and didn’t want the tail to become cluttered by a traditional licence plate bracket so an elongated mount positions the plate much lower over the rear wheel, which should keep the spray away from the rider’s back. Since the forks (from a sportier RS100) had been lowered the rear end had to follow suit, so as to maintain the all important bone line, a single Yamaha R6 shock takes care of stance and offers a degree of adjustability.

The 3-spoke wheels have been superseded by a more handsome pair from an older machine and classically treaded Avon Roadriders are responsible for keeping all this endeavour upright. The ABS pump and plumbing has been removed in the quest for a cleaner look and more analog riding experience.

Obviously the original fuel tank would have looked well out of place with the nose fairing and aforementioned rear so here’s today’s pop quiz; name that tank. Nope, me neither. It’s from an early Suzuki GS1100, made to look more swoopy thanks to the painted knee pads. The all important, and nowadays recognisable, Ad Hoc logo has been upgraded to laser-cut steel – classy.

A fans choice HP2 blue and white paint scheme breaks up the black monolith of an engine and transmission unit and looks great with the tinted screen. To temper the classic styling slightly David fitted a rectangular headlight.
The airbox is no longer, cone filters taking it’s place which required tweaks to the fuelling to ensure that big-four remained silky smooth. But a café racer would be dull without at least an upgraded soundtrack, so the exhaust has been shortened and lightly de-baffled.

David’s work continues to attract the attention of not only willing and eager customers but also manufacturers, and rightly so. Keep an eye on the Bike Shed for news of his grander, more modern plans.

via The Bike Shed