“Wow what is that?” Allow me: Urwahn top dog. Anyone who cruises through the city on this pedelec should be prepared for questions from bicycle-savvy people. The core of the top dog is the combination of a steel frame, which was produced using the 3D printing process, and an electrical auxiliary drive from the automotive supplier Mahle. The pedelec weighs only 14 kilograms, is extremely stable at the same time, it is agile and very precise. In other words: the Urwahn bike is a source of joy.
(Image: Christoph M. Schwarzer)
Most noticeable on the Platzhirsch is the interrupted seat tube in the frame. A fascinating element: subjectively, the entire frame appears extremely rigid. And yet it objectively has its own damping. Urwahn shows that in one Security check video according to DIN ISO 4210 (from timecode 0’41 “) according to: The frame is slightly flexible at the rear under vertical load. In connection with the high flanks of the Continental Urban Grand Prix tires and the gel saddle (Ergon GA30) the top dog remains sporty, without being overly tough, just the right minimum dose of comfort for everyday use.
Regional production instead of Asian imports
Sebastian Meinecke, Managing Director and Lead Designer at Magdeburger Urwahn Engineering GmbH, sums up the 3D printing process: “Ultimately, it is a layered welding process.” The starting material is a powder that is obtained through the so-called atomization of steel. The frame tubes, which are created in a separate process, come together with the 3D printed parts at Rotor Bikes and are welded there by hand. “All in all, it only takes three working hours,” says Meinecke, “and further partial automation using laser welding robots is possible.”
With this regional frame production, Urwahn stands out from the competition, which orders almost in unison in Asian countries such as Taiwan, Vietnam or Cambodia. This year the aim is to manufacture up to 150 bikes, which shouldn’t be a problem because the 100 has already been exceeded. A good 60 of them are made up of the electrified top dog, the rest is made up of the conventional city fox. Delivery time: 45-60 days after order.
Light Mahle drive
For those of hot cars driven single-speed version with Gates Drive (alternatively: Shimano XT derailleur 11-speed) the customer has the choice between a ratio of 60 to 20 or 55 to 20. If you are in a certain condition, you should definitely use the long ratio built into the test bike. The Mahle X35 drive (aka “ebikemotion”) pushes noiselessly, smoothly and smoothly. Three, four, five kicks and the legal 25 km / h limit has been reached. Pedaling is possible without any problems – provided you have enough leg strength. A mode that sets itself quickly. The part goes like hell.
The Mahle drive differs significantly from the Bosch mid-range motors. It is actually the much-cited tailwind when accelerating. Powerful and felt pretty natural. The electric motor regulates very precisely. And, as I said, it offers the important option of pedaling beyond 25 km / h; here the Mahle system is reminiscent of that of Fazua Evation. As a result, the battery, which is relatively small at 250 watt hours (Wh), is automatically saved. Even on extended 50 km tours through Hamburg, the electrochemical storage unit could not be broken down. Our tip: Do without the additionally available drinking bottle battery with 208 Wh. Basically, it is nice to see how much the pedelec drive market has become differentiated and professionalized in the meantime, and the current state is certainly not the end of development.