BMW Carbon Fibre Frame Discards Swingarm Pivot

BMW’s newest carbon fibre frame has discarded the traditional swingarm pivot and in its place, it uses, erm…., carbon fibre that is flexible. Now, the German manufacturer has plenty of experience when it comes to handling carbon fibre. It has been using the material on a large scale from as early as 2003.

Models like the BMW M3 CSL, i3, i8 and 7 Series have all been manufactured by making use of carbon fibre in varying degrees, along with other materials. Also, the boffins at BMW Motorrad have used the carbon fibre frame in the non-road legal HP4 Race already. The frame on that bike weighs only 7.8 kgs.

The new frame seen in the patent image looks like an evolution of the HP4 Race’s chassis, with the biggest difference being the fact that the swingarm pivot has been ditched.

Carbon fibre can be engineered to be rigid in one direction and flexible in another. BMW has used this concept to create a frame that will possess lateral stiffness and yet bend to absorb bumps.

We suspect that dampers will be used still, since the flexible carbon in itself cannot provide all the damping needed (yes, even on a race track) and more importantly, it would allow for suspension setup changes.

However, this technology is not entirely new. Competition cars across various racing events have long been taking advantage of the flexible nature of carbon fibre.

They mostly use it in their suspension design so as to get rid of the pivots which attach the wishbones to the chassis, thus increasing strength, reducing weight, all in the search for better lap times.

With the patent image, we know that development of the BMW carbon fibre frame is underway. It might well be used on the successor to the mad HP4 Race and will be one of a kind, that is until other manufacturers follow suit, now that the patent image has been leaked.