Claims that Swiss rider Fabian Cancellara could have used a hidden electric motor during his career could be investigated by the Union Cycliste Internationale (UCI).
The allegation was made by American former pro rider Phil Gaimon in his recently published autobiographical book Draft Animals.
Gaimon wrote about Cancellara's Classics victories in the 2010 Tour of Flanders and Paris-Roubaix, saying: "When you watch the footage, his accelerations don't look natural at all, like he's having trouble staying on the top of the pedals".
A UCI spokesperson confirmed to Cycling Weekly that its newly-elected president David Lappartient has said that they are "not ruling out the possibility of investigating, especially if new information was made available".
The UCI said that it would not be commenting further.
Gaimon's claim regarding Cancellara's performance in the 2010 Classics is not new after a YouTube video was posted shortly after his victories purportedly showing Cancellara accelerating away from rivals due to 'motor doping'.
Cancellara has not commented so far on Gaimon's book passage, but said after the original allegations surfaced in 2010 that he has never used a hidden motor. “I have showed that over the last 10 years that I have an engine in my body, not in my bike," Cancellara said.
"I think three million people watched YouTube and those people think they can create a problem. I don’t want to go into the subject of where is the button, how I changed gears. Come on!"
Hidden electric motors have been found in rider's bikes at events, though not as the highest level.
Belgian rider Femke Van den Driessche was found to have a hidden motor in her spare bike in the pits at the Under-23 cyclocross World Championships in 2016.
Earlier this year, an amateur rider was caught with a hidden motor at a race in France.
On Friday, the UCI announced the appointment of former professional Jean-Christophe Péraud as its Manager of Equipment and the Fight against technological fraud.
Part of Péraud's role will be to co-ordinate checks for concealed motors.
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