In the mid 90s, the K1100 RS sat at the top of the BMW range. It was the sport tourer par excellence, at home on the autobahns and interstates. A fully-loaded RS would be nudging 600 pounds on the scales, but that mattered less than its ability to cruise at triple-digit speeds all day long.
Fast forward thirty years, and there are much better machines than the Reisesport (travel sport) for long haul mile-munching. But the K1100 has good bones, and the inline four engine, laid over on its side, has both torque and power to spare. Which makes it an excellent choice for a custom bike, especially if the heavy fairing is starting to show battle scars.
This spectacular café racer is one of the sharpest K1100 builds we’ve seen, and suggests that the platform is coming of age in the custom scene.
The man behind the machine is Tim Somers—the founder of the Dutch BMW parts specialist Powerbrick. Tim made his debut on these pages last week, when we featured the R9T he built with his compatriot Arjan van den Boom.
This solo effort is very different to Cloud 9, but just as appealing, with stripped-down visuals matched to clever engineering. Tim’s background is industrial design, and he’s gone to town on this K1100—using CNC machining for the aluminum and stainless-steel parts, and 3D printing for the front and rear bodywork.
“The visual lines were my main focus,” he tells us. “I wanted to build a bike that made sense from every direction, with the main line being the top curve—running from the front of the Koso Thunderbolt headlight over the tank to the rear cowl.”
“It makes the bike ‘low’ and gives it an aggressive stance.” That stance is accentuated by the swingarm, which has been extended by 15 mm (about 5/8”) despite the complexity of the Paralever design.
The swingarm is hooked up to a YSS G-Racing monoshock, which has adjustable hi-low speed compression as well as the usual range of knobs to twiddle. It’s flanked by Powerbrick’s own rearsets, milled from aluminum.
The front end has been completely overhauled, with S1000RR forks using Wilbers lower stanchions and Bitubo cartridges. The forks are attached using Powerbrick’s own triple tree kit, crafted from aluminum, and anodised in black. It’s fitted with adjustable steering stops and an insert for the Motogadget motoscope mini digital instrument.
The clip-ons are furnished with Motogadget bar-end indicators and Biltwell grips, and Tim has also installed a Brembo RCS19 brake master to feed the Brembo HPK GP4-RS monobloc radial front calipers and Serie Oro discs. They’re connected by Venhill brake lines.
The K1100 RS engine pumps out around 100 hp in stock form, but Tim has boosted this with DNA air filters, new ignition parts from NGK, and top-spec Bosch EV14 injectors. He’s also ported the intakes to get more air entering the engine, and slightly advanced the timing.
He’s also grafted on a free-flowing stainless steel exhaust system: a 4-into-1 layout terminated with a stubby muffler. And temperatures are kept in check by an aluminum radiator from RC Racing, plumbed in with Samco silicone hoses. Power is now an estimated 130 hp.
Tim has kept the heavily scalloped standard tank but ditched the rest of the bodywork—which must have saved more than a few pounds of weight. A new subframe keeps the lines tight and provides a connecting point for the revised monoshock arrangement.
Under the hood, there’s a new electrical system wired up to a Motogadget mo.unit blue box which can be controlled via Bluetooth. There’s also a NOCO lithium battery with a discreet Ctek charging point alongside.
If all this butters your toast, you’ll be glad to know that the K1100 is for sale. Tim will even include a Ctek charger, and swap out the Pirelli Diablo Rain race tires for road legal rubber.