Electric bikes have a lot of qualities, but they also have the disadvantage of being often very heavy. It is sometimes very difficult to take them under the arm to store them at home, as long as you live on top of a building without an elevator.
This weight problem was brilliantly solved by Dennis Freiburg, an engineer living in Dortmund (Germany), who designed and built the Freicycle. A bike that does not exceed 7 kg (6.872 kg exactly)! The two-wheeler prototype has earned its place in the Guinness Book of Records. While waiting for proper marketing?
A Guinness record
The handyman started out on a base of the Merida Scultura bicycle, designed in carbon fiber and weighing less than a kilo. A material that the engineer used as much as possible given its reduced weight: wheels, handlebars, cranksets. The other components, like the pedals, have been 3D printed, always with the aim of making them as light as possible.
But we also had to think about the engine and the battery, critical components not easy to lighten. For the engine, Dennis Freiburg simply started with a friction movement from a helicopter engine… A scale model, of course! This small motor, wrapped in an abrasive case for better grip on the rear wheel, is still capable of delivering 600 watts of power. The Freicycle can spin up to 48 km / h, quite decent with such an engine.
As for the battery, it has a capacity of 137 Wh, which is not much, but the range of the bike is still between 19 and 35 km. The component is cleverly slipped inside a gourd (also in very light metal) held by a bottle holder printed in 3D as well. Fun wink, the bottle cap serves as a switch!
“A lot of people don’t believe this is an electric bike! The engineer laughs. “They keep weighing it and lifting it up, they’re really amazed at how light it is.” Now all that is needed is a manufacturer to offer something similar for the general public!