Here's a great article about Quantya that was recently published at Der Spiegel Online
http://www.spiegel.de/international/germany/0,1518,576573,00.html09/05/2008
BATTERY-POWERED BAD BOYElectric Motocross Bike Could Redeem Rebel Sport
By Christian Wüst
The deafening engines that send motocross bikes shooting off jumps and tearing up hillsides have earned the cycles a bad reputation. But a German entrepreneur wants to rehabilitate the sport -- with an all-but-silent new engine.
The Quantya is an electric motocross bike. Its silent motor might help redeem the sport's deafening bad-boy image.
At first glance, the Quantya motocross bike doesn’t leave a particularly tame impression. It looks like the usual cross-country motorbike, a vehicle for daredevils, the kind of riders who plow down muddy tracks and off high jumps with no regard for the natural world around them. And then, of course there’s the noise: the motor’s guttural RrrrraaaangtangtatatAAANG. Hardly any recreational sport has won so little acceptance in polite society.
Yet the Quantya is different. It can take on rough terrain just as well -- and no less destructively to the ground it covers-- as traditional motocross bikes, but with a difference. The Quantya does it silently, moving almost as noiselessly a bicycle. What’s the secret? The bike’s power source is electricity, not gas.
In far southern Germany fans of the sport can now try out this new form of motocross in one of the first “Quantya Parks,” which opened its doors in the tiny Bavarian town of Siegsdorf a few weeks ago. For €15 ($22) per quarter-hour it offers bikes for rent and access to a course that should challenge even the most skillful in the sport.
Town mayor Thomas Kamm, in a traditional Bavarian jacket, watches respectfully as amateur motocross enthusiasts do meters-high jumps along the course on the electric-powered bikes. “The visual and the sound experience don’t match,” says the mayor, and it sounds like he likes that fact a lot. It's exactly this incongruity that led Kamm to authorize construction of the park in the first place, although it sits next to a tennis court and within earshot of a residential area. And indeed, all that can be heard as the bikers do their tricks is the ever-present drone of nearby lawnmowers.
Businessman Hans Eder, 41, wants to open 50 to 70 such Quantya Parks in Germany and Austria in the next few years, with the goal of redeeming this outlaw among recreational sports. Eder, who offers motocross rider training courses, watched for years as his passion for the sport became more and more of a forbidden love. The number of motocross courses kept shrinking, and the outlook for new facilities looked bleak. “You’re more likely to get a nuclear power plant approved,” a building contractor friend told Eder.
It’s the same problem everywhere: noise. The demands of motocross bikes -- that they be extremely powerful and yet as light as possible -- led inevitably to loud motors. Eder saw only one solution: electric power.
Lithium Polymer Battery
Almost four years ago, Eder’s vision of electric-powered bikes led him to another motocross enthusiast living near Lake Lugano in Switzerland. Claudio Dick, once an importer of Italian motorcycles, was one of the first to experiment with electric power and motocross. At that point, however, Dick’s work consisted mostly of waiting for a suitable battery.
In the first prototypes the pair built, the rechargeable battery ran out after just seven minutes -- which wouldn’t do at all. Eder and Dick set themselves a goal: The bike’s battery had to last at least 30 minutes. Any less, and there would be no point.
Then battery development took a great leap forward. In the spring of 2007, Dick called his colleague in Bavaria and said, “It rides two hours.” Eder replied, “You’re lying to me!” He travelled to Lugano and took a turn on the bike, charging the battery once and riding almost soundlessly through the woods for two hours and ten minutes. It seemed the Quantya was ready for the market.
The electric motocross bike entered the scene with some impressive qualities. The motor provides 16.8 kilowatts of power (22.8 horsepower) and accelerates the bike, which weighs just under 100 kilograms (220 pounds), with a torque of 38 joules, equivalent to that of light motocross bikes used by professionals. With one charging of the battery it can cover 40 to 50 kilometers, which makes for about a two hour outing.
On the Quantya, the electric motor is located where the gears would otherwise be. It drives the chain directly. With just one gear the bike can achieve up to 80 kilometers per hour (50 mph). And where the motor traditionally sits, the Quantya has a lithium polymer battery. The battery looks something like a spare gas canister. It weighs 19 kilograms, and according to Dick it can store about 2.3 kilowatt hours of electricity -- at the top end of batteries worldwide. The Quantya’s battery cells are bought from Kokam, a suppler in South Korea. The control electronics come from Switzerland, and the motor from England.
It’s the battery that makes the Quantya so expensive. The rechargeable batteries cost about €2,000 each, five times the cost of the engine transmission unit for a small conventional bike.
A version of the bike approved for road use is now being sold in Germany for €9,282, about €2,000 more, for example, than a conventional 250cc motocross bike from Austrian motorcycle manufacturer KTM. The manufacturer’s warranty covers the battery through being charged 1,000 times, which comes out to a maximum of 50,000 kilometers (31,070 miles).
With those specifications, the Quantya will hardly open up a mass market. Instead, Eder plans to focus at first on the rental bikes in his Quantya Parks -- and on heralding the new, environmentally friendly face for his discredited sport.
As an additional green aspect, every Quantya Park will be equipped with a photovoltaic array, putting at least as much electricity into the power grid as the park’s motocross bikes use. It’s a bit of an energy revolution, in the spirit of new, environmentally-friendly sports. As Eder says, “We can’t always work against humanity.”