Image 1 of 4 Zdenek Stybar (Czech Republic) in his third cyclo-cross rainbow jersey (Image credit: Bettini Photo) Image 2 of 4 Zdenek Stybar (Czech Republic) rides towards the rainbow jersey (Image credit: Tim de Waele/TDWSport.com) Image 3 of 4 Sven Nys (Belgium) out on course (Image credit: Bettini Photo) Image 4 of 4 Danilo Di Luca (Fantini Vini - Selle Italia) (Image credit: Bettini Photo)

The UCI checked the bikes of the first three of the world championships in Hoogerheide for mechanical doping. UCI officials removed the saddles from the bikes and used a camera to check inside the seat posts for the presence of motors, Het Nieuwsblad reports. No motors were found.

It was the first time the international cycling union checked for mechanical doping after the interview by Danilo di Luca on Italian television in January. Di Luca claimed that the use of motors inside the bike frame would be possible.

There was controversy in 2010 regarding Fabian Cancellara allegedly having used mechanical assistance to win both the Tour of Flanders and Paris-Roubaix. The allegations were unproven and Cancellara denied them.

"I know how I achieved my wins. I have an engine, but it's in my body. This is the strongest one you can imagine. Over the last decade I've shown that I don't need any other motor," Sporza reported Cancellara as saying at the time. "It's frustrating that these stories keep popping up about me, but that's life."