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BMW K-bike successor revealed!

By Sean Alexander, Oct. 23, 2003
The big news around BMW here in Germany, is the release of first details of the upcoming replacement for the K Series. Unfortunately, the news broke as an exclusive in the print media, so no online photos just yet, but they'll show fairly soon.

-Sounds good to us! Rumors surrounding the new BWM's have been quite intriguing. We promise to bring you more info as it becomes available. - MO

Its all pretty radical. A 16V inline four designed for 1000-1300cc variants mounted across the frame is not exactly a novelty outside the BMW-Welt. However, starting with the hefty forward slant of the cylinders (60 degrees) and state of tune (160 to 170PS) things start getting pretty interesting. Next is the use of a chain/gear drive for the camshafts (chain to exhaust cams, gears from that to a counter-rotating inlet cam). Starter motor and alternator sit piggyback atop the gearbox to produce a compact unit allowing a long swining arm. Very un-BMW-like is also RAM air and a short-stroke format laid out for 11,500rpm in the launch engine (1200cc sport/touring tune).

The frame is genuinely radical: a cast dual-spar design with a Hossack fork up front and single sided shaft drive rear. What's a Hossack fork? The layout is stacked triangular 'wishbones' at the front mounted top and bottom of the frame spars just above C of G. The tips of these 'wishbones' (actually triangular structures) hold the stearing shaft in ball joint head bearings. The handlebars pivot on a completely seperate, much lighter, stearing bearing and drive the forks via a 'scissors' linkage. Mechanically this is a step up even from a telelever since not only is braking dive eliminated to whatever extent the designers fancy, but rake/trail remain more or less constant throughout the suspension range. The other big advantage is that braking forces can act lower, with lower leverage directly on the main frame spars, eliminating the need for a hefty stearing/fork casting high up above the centre of gravity. The rear is a further refined (stiffer lighter) version of the shaft-drive single-sided swingarm, seen on the current boxer twins. The total package aims at hitting an genuine on-road weight below 250kg for the launch model (supposedly fully faired sport-tourer with a 285km/h Vmax).

Brakes, ABS etc etc... all supposed to be uprated / sportier than the current stuff too. Basically, it look likes it is 'auf widersehn Cruise-ship' and 'hello Uebersports' for the Four-cylinder Beemers.