Aerodynamics applied to production motorcycles has various functions, which in summary affect performance, comfort, engine cooling but also appearance. A patent filed by BMW shows movable aerodynamic appendages to maximize the relationship between comfort and aerodynamic performance. However, instead of using electronics, patents that have surfaced show that BMW engineers are taking a low-tech approach instead of using electronics.
BMW has filed a patent concerning mobile appendages intended to increase aerodynamic protection without penalizing the aerodynamic coefficient, and which does not use any electronics, and in an ingenious way.
Something similar was seen on the new Moto Guzzi V100 Mandello, which has two movable deflectors positioned between the tank and the front fairing whose opening / closing is managed by software and electric servomotors.
The principle developed by BMW aims to simplify the system as much as possible and its concept can be applied to different motorcycles by exploiting their designs and features. This patent was presented with three movable deflectors on both sides of the motorcycle, at different heights and in the front area.
Their opening is simply controlled by suitably calibrated springs, so that at low speed the extension of the springs leaves them completely open, and they close as the aerodynamic pressure brought by the forward speed increases. increases, eventually flush with the surrounding fairing to reduce – or perhaps eliminate – drag at high speeds.
A simple idea, as it allows a greater surface area capable of deflecting air away from the rider at low speeds, while at high speeds it will be up to the fixed aerodynamic shape to divert the flows away from the rider and passenger, thus maximizing the aerodynamic efficiency in the fundamental comfort/performance ratio for a production motorcycle.
BMW's patent also explains that the system can be easily modified by simply changing the spring stiffness to change the deployment of these air deflectors. They can be set to fold as speed increases, and also remain fully extended up to around 48 mph and retract fully at around 120 mph.
Additionally, design drawings show a three-baffle configuration – one mounted low, another mid-height, and the third relatively high on the fairing. Theoretically, each could be set to retract separately with springs of different strength. Also worth noting is the patent's intentional wide range, meaning there are virtually no limits to shape, size or mounting position.
The patent filed by BMW was designed on a model from the GS family, but its application can extend to very different models. Although this patent alone is far from confirming that the idea is being developed for mass production use, we are certain that it will make its way onto a future BMW model.
