BMW V-8 Engine Motorcycle - Das Hoss - Wild File

Using A BMW V-8 Engine, Dentist And Bike-Builder Extraordinaire Harald Geiling Builds A Germanic-Flavored Boss Hoss. Weird Harald, Indeed!

By Roland Brown, Photography by Phil Masters

Riding Harald Geiling's highly unique Beemer is a distinctly uncomfortable experience. My ears are ringing from the wind and the roaring eight-into-one exhaust, and my legs are being wedged apart by the width of the massive V-8 car engine. Every time I twist the throttle my arms are yanked uncomfortably straight by the vicious acceleration of a bike that produces almost 300 horsepower. But this mad machine is so entertaining I can't keep a smile off my face.

Perhaps only someone with the varied talents of 47-year-old Dr. Geiling, from Mainz, Germany, would even contemplate designing such a mixed-up motorcycle, let alone actually build the brute and put it on the road. As well as running Roadrunner Bikeshop, one of Germany's biggest Kawasaki dealerships, Geiling dabbles in building development and works two days a week as a dentist-hence the Dr. title in front of his name.

The crazy Doktor can't remember the precise moment he decided it would be a good idea to build a bike around a BMW car engine; he says it was some time after his girlfriend's father had damaged his car's engine, and Geiling had offered to find a replacement. Seeing a naked V-8 car engine fired his imagination, so he used the broken lump to design this two-wheeled creation before eventually buying and installing a running engine, which originally powered a '94-spec BMW 740i sedan.

Apart from being busy with three jobs, Geiling was in an ideal position to handle such a project. Not only is his dealership overflowing with bike spares, but it's also one of Germany's leading motorcycle frame repairers, so Geiling is used to rebuilding chassis of everything from scooters to alloy-framed sportbikes. In fact, his mighty special doesn't really have much of a frame-just custom-made tubular steel subframes bolted to the front and rear of the enormous, 3982cc liquid-cooled powerplant.

At the front, the subframe incorporates a large tubular crashbar, built to shield a radiator that originally came from a Volvo 340 auto. Two fans sit behind it, but the engine, open to the air instead of shrouded by car bodywork, runs so cool that they're not needed. The DOHC, 32-valve, 90-degree V-8 itself produces a claimed 286bhp at 5800 rpm in car duty, and is left internally standard. It's mounted with its crankshaft running down the length of the bike, and with its two big camshaft covers sticking up on either side.

"The theme of the bike is long, low and powerful, and it is certainly all those things," grins Geiling. "The engine was a perfect choice-it's as though it was designed for a motorcycle. But even so, the bike was a great deal of work. It took me four years, and I gave up counting how many hours I'd spent on it when the number got above 1000."

Some of those hours went into fashioning the fuel tank, which sits below the front of the similarly purpose-built seat. The modified 740i injection system is fed by a rather incongruous blue plastic pipe on the right side of the engine instead of via the car's large airbox. The original exhaust downpipes lead to a specially built eight-into-one system that ends in an unbaffled silencer from a Kawasaki ZXR1100.

One of the most complex engineering jobs was the transmission, which combines a modified standard clutch with a two-speed gearbox Geiling designed and built himself. Output is via the drive shaft from Kawasaki's Concours sport-tourer, then an 85mm-wide belt to the rear wheel. The 18-inch wheel is from a ZXR750. The rim was widened to 9 inches with two rings of aluminum so it can carry a suitably huge 240/40-section Metzeler Marathon tire.

Geiling's supply of Kawasaki parts came in handy for several of the bike's other components, including the front end's assembly of triple clamps, inverted fork tubes, disc brakes and six-piston Tokico calipers. All those came from a Mean Streak cruiser, as did the round, chrome headlight. The front wheel was originally from a ZX-7R and was widened to 4.5 inches before being fitted with Metzeler MEZ1 rubber. Rear shocks from two ZX-7Rs are mounted horizontally, operated by a swingarm that Geiling built around the unit from a ZZR1100. Tailpiece and footrests are from a ZX-9R.

Enjoyed this Post? Subscribe to our RSS Feed, or use your favorite social media to recommend us to friends and colleagues!

*Please enter your username

*Please enter your password

*Please enter your comments
Not Registered?Signup Here
(1024 character limit)
  • Motorcyclist Online