Aerodynamics has become one of the hard-fought battlefields in motorcycle racing and we're already seeing the idea of winglets trickle down into road-going bikes—so perhaps this idea from Honda is the inevitable result. The be-winged streetbikes we've seen so far have all been influenced by the ideas emerging in racing; Kawasaki's H2R, Ducati's Panigale V4 R, and Aprilia's latest RSV4 1100 Factory all sport fairing-mounted winglets like those used in MotoGP for the last few years. But Honda has always been a firm that takes a more considered approach than most, and this patent application reveals how it might bring downforce to its streetbike range.

Honda mirrors
Honda’s patent drawing for mirrors that create downforce.US Patent Office

The idea is blindingly straightforward; modern road-going sportbikes already have large protrusions on either side in the form of their mirrors, so why add more winglets? Instead, Honda proposes wing-shaped, downforce-creating mirrors. The bike illustrated in the patent drawing is a current-model CBR1000RR. That bike is understood to be in line for replacement in 2020, so it’s unlikely to be the actual recipient of these mirrors. But its replacement would be the perfect machine to use them on.

The aerodynamic design in itself is quite straightforward, with a concave upper surface and a convex lower, creating an inverted wing shape that creates a pressure differential between the upper and lower surfaces. With high pressure above and low pressure below, the result is downforce.

Honda aero mirrors
A concave upper surface and concave lower surface on Honda’s aero mirrors create downforce.US Patent Office

Honda has boosted the downforce-creating effect by adding upturned outer edges to the mirrors. These work like the flipped-up wingtips of modern airliners, helping prevent the higher pressure air above the mirror from spilling over into the low-pressure zone beneath it.

As on the existing CBR1000RR, the design incorporates the turn signal into the front of the mirror, reconfirming that this is an idea aimed at road-going production bikes, not racers. Whether race regulations would allow Honda to replace the downforce-generating mirrors with wings on race versions of the bike remains to be seen.