The Bike Motor That Sparked a Scandal — and Never Made a Sound

Before e-bikes became brunch-table staples in Venice and Greenpoint, there was one electric motor no one wanted to talk about.

In the world of competitive cycling, there are few insults heavier than “mechanical doping.” It sounds like something from a sci-fi paperback—something secret and sinister and utterly ridiculous. A hidden motor? In a racing bike? Please.

But what if it were true?

Rewind to 2008. E-bikes were barely a blip outside of Asia, still bulky and utilitarian, associated more with delivery drivers than design-minded commuters. But in Austria, an engineer named Thomas Gruber had something else in mind: a whisper-quiet, nearly invisible motor tucked discreetly into the seat tube of a traditional bicycle. It was called the Gruber Assist, and if you didn’t know what to look for, you’d never know it was there.

It wasn’t marketed to pros, of course. This was billed as a discreet tool for everyday riders who wanted just a little extra push uphill. The design was pure stealth: a 200-watt motor activated by a button near the handlebars, quietly feeding power directly to the crankshaft. It was light. Seamless. Ingenious.

And it didn’t take long for whispers to start swirling around the European pro cycling circuit.

In 2010, questions started to follow Swiss cyclist Fabian Cancellara after two dominant performances. Some claimed to spot him pressing a button on his bars mid-race. His accelerations looked... too clean. Too strong. Too easy. It was pure speculation, but it planted a seed. Was someone actually racing with a hidden motor?

That paranoia burst into reality in 2016, when 19-year-old Belgian rider Femke Van den Driessche was caught red-handed at the UCI Cyclo-cross World Championships. Tucked inside her bike? A motor. Likely a descendant of the Gruber Assist, by then rebranded under a new name. It was the first official case of “technological fraud” in the sport—and it was just sophisticated enough to suggest it wasn’t the first.

The story of the Gruber Assist isn’t just a footnote in cycling history—it’s a parable. A tale of temptation. A question about where performance ends and ethics begin.

And, let’s be honest, it’s also a damn good story.

Because long before e-bikes became the elegant commuters they are today, someone was already dreaming of a way to make riding easier—without making it obvious. A little power, hidden in plain sight. The feeling of flight, disguised as a pedal bike.

We can’t help but admire the ambition, even if the intent was questionable. At Linus, we’ve always believed that the best e-bikes are the ones that ride—and look—like bikes. The motor is there when you need it. The beauty is always visible.

Sometimes the best kind of assist is the one that doesn’t announce itself.