Based on my R80 E-drive concept of reusing the engine crankcase of the R combustion engine. Why not exchange the entire engine with an Electric drivetrain while keeping the BMW aesthetics of the R engine.
Based on our basic 7 sense: taste, movement, balance, smell, vision, touch and hearing. My thoughts on some of these senses are could be linked to certain aspects that make motorcycle riding an experience. Smell of oil and gas, vision of our surrounding going places, touch to textures and heat, movement and balance to speed and handling and hearing as a prime sense to safety since it’s the only sense we have that doesn’t have to place us within direct contact with a situation to have immediate impact (you could say the same for smell but that takes a while). For example someone could drop a mug of coffee around the office corner and you have an instant reaction and idea of what happened. So why make E-drive silent?
Give E-drive the sense of functional sound, the sound to indicate: the engine is on, someone is approaching, acceleration, speed, malfunction (we have all heard the weird ticking noises in our cars at some point). This sound could easily be generated though mechanical principles since it’s nothing else than frequency air displacement.
Next to functional sound the memory and movement handling of a regular bike, instead of a one geared E-drive. Ad a gearbox this keeps the experience of doing something with your machine. As well as lowing the load on the electro motor. Basically 8KW at 10kRPM that could approach 120khp a 4kw engine with gearing to approach 120kph at 5kRPM. Less RPM less Amps needed, less batteries to carry around. It may not be maintenance free implementing a gearbox but adds significant value to riding an electric motorcycle with sound.