The Wattman, from French motorcycle manufacturer Voxan Motors, is the first high-performance electric motorcycle made by the company specially designed for the latest world speed record project. In July 2021, the Voxan Wattman will attempt to set a new world speed record on the Salar de Uyuni salt flat in Bolivia. Riding the motorcycle will be six-time motorcycle racing world champion Max Biaggi.
Voxan Motors, part of the Venturi Group, is partnered with global telecommunications company ROKiT Group. In turn, the ROKiT Group is also title partner of Venturi’s Formula E Team, ROKiT Venturi Racing.
“When Venturi President Gildo Pastor showed us the Voxan Wattman and talked me through the world speed record attempt we were very impressed by his vision, ambition, and the commitment of his team in creating the technology involved,” said ROKiT Group Founder, Jonathan Kendrick. “To have our ROKiT red livery on such a unique piece of electric engineering reflects our ethos as a group of companies and is a real honor. Gildo is a true pioneer and we are delighted to partner with him and Voxan Motors on what we hope will be a highly successful and ground-breaking record attempt.”
The Wattman is the product of a pioneering development process, in terms both of its design and the technology behind it. The motorcycle is an entirely new concept, not based on any existing vehicle. When the teams at Voxan Motors first began working on the project in the autumn of 2018, they started totally from scratch with a blank page. From there, the company says everything quickly snowballed.
"We were keen to move fast," explained Louis-Marie Blondel, who both oversaw the project’s development and personally test-rode the motorcycle. "So, we focused on two main points: drag (aerodynamics) and stability at high-speed. We were aiming to have the smallest possible projected area but with a long wheelbase and a large rake so the rider would be positioned as low as possible. We then identified a target speed, based on the existing record, which was originally 203.56 mph (327.6 km/h), but which was set at just over 204.48 mph (329 km/h) by Ryuji Tsuruta, riding a MOBITEC EV-02A in the autumn of 2019. That made no difference to our roadmap, as we were already aiming for a minimum of 205.05 mph (330 km/h)."
Unique qualities set the motorcycle apart
According to the company, the Voxan Wattman boasts some special technical characteristics that set it apart from conventional motorcycles. To maximize the distance between the front and rear wheels (a longer wheelbase provides more stability), engineers designed the motorcycle with a double-wishbone front suspension, rather than a telescopic fork. This keeps both sides of the wheel clear, a practical solution that helps lower drag while allowing for quicker and easier replacement, reports the company. The bike is steered by a link and swingarm, allowing the rider to sit further back and lowering the machine’s center of gravity. The chassis is made from aerospace-grade steel, while the running gear and wheel rims are aluminum.
"There is no front brake, for several reasons," said Franck Baldet, the project’s Technical Director. "Firstly, it’s better aerodynamically at high speed, but also on the vast salt flats it takes quite a while to accelerate (due to the low grip surface) and we have plenty of room to slow down. Last, but most importantly, front wheel braking at very high speed on a salt flat can unbalance the motorcycle and cause a fall. We aren’t using a parachute, but the rider does have a rear-wheel brake, which he controls with the left handlebar grip, and also engine-braking controlled by a small lever on the right handlebar grip.”
Unlike other motorcycles, the Wattman has no conventional cooling system. This means it is able to dispense with a radiator, something that is seen as an aerodynamic disadvantage. To prevent overheating, the fluid present in the circuit is cooled by dry ice (carbon dioxide compressed to the solid state, "dry" ice that does not become water when it melts), contained in a tank mounted under the seat. The cooled fluid is then pumped through the cooling circuit which runs through the heart of the powertrain.
In conventional industrial settings, the battery is usually sourced off-the-shelf from a partner manufacturer. However, the unique nature of this motorcycle, the limitations posed by the battery’s weight (nearly 50% of the Wattman’s total mass), and the required level of performance all meant that the company found no battery on the market that fit the bill. So Voxan Motors’ engineers decided to design the power unit themselves. To do so, the team based in Monaco enlisted the help of Venturi North America, the Group’s subsidiary based in Columbus, OH, at the campus of Ohio State University, where the battery was created and built. The challenge for the engineering students was to find the parts that offered the best possible power to-size ratio, since range is not a priority for a world speed record attempt. With 1470 cells, the Voxan Wattman’s battery delivers 317 kW of nominal power, with a capacity of 15.9 kWh.
For more information, visit www.venturi.com.