BMW motorcycles may not have entered the electric motorcycle party very early, but the company is now making up for this with products that may become the industry’s first driveshaft electric motorcycle. BMW likes driveshaft motorcycles, but the electric motorcycle industry is not so keen on them. Electric motors and batteries allow motorcycle manufacturers to get rid of the typical design constraints of gasoline transmissions. Due to the modularization of electric motorcycle components, the designer got rid of the traditional gasoline tank and bulky internal combustion engine and gained unprecedented freedom. Nevertheless, most of the innovations have entered interesting battery designs and locations.
Outside of Harley-Davidson LiveWire, the motors are still cross-mounted, and there is little difference between manufacturers. The traditional cross-mounted motor creates a simple and easy method to connect the output shaft of the motor to the rear sprocket or pulley through a chain or belt drive, respectively. Some electric motorcycles choose to downshift, while many other electric motorcycles simply use a direct-drive setting, but BMW has explored driveshaft designs for its electric motorcycle concepts, such as the Vision DC Roadster. Now, a new patent shows how this system works. As you can see from the patent drawings, including the driveshaft will give BMW more freedom in engine placement.
It will also create the potential for interesting gear reduction options. The planetary gear system (marked as item 20) can be seen in the patent picture, which will enable BMW to use stepped high-speed, high-efficiency motors. The patent drawing also shows various motor position options, including longitudinally-mounted motors that are coaxial and offset from the bicycle’s long axis. Such a free position can pave the way for some of the weirdest and futuristic motorcycle designs we have seen in BMW concepts.
Although we initially thought BMW was just throwing crazy designs on the wall to see what the company will leave when it launches its first Vision DC Roadster electric motorcycle concept in 2019, the new design submissions indicate that the manufacturer may be stepping up production bicycle. In addition, it can make BMW the first electric motorcycle manufacturer to offer mass-produced electric bicycles with this axle drive configuration.