A leading group campaigning for cleaner cycling has written an open letter to the UCI and the World Anti-Doping Agency (WADA) expressing concern over the lack of doping tests at a number of recent major cyclocross events.

According to Bike Pure “there hasn’t been a single dope test, either blood, urine, or mechanical doping at any major European cyclocross event since the World Championships (January 28-29). That has included two SuperPrestige series races and one DVV Trophy race.

The letter quotes a professional rider who expressed concern about the lack of testing to Bike Pure: “To have no bike or rider testing at events such as the SuperPrestige and DVV Trophies is more than alarming.

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“Considering Femke [Van den Driessche whose bike was found to have a motor at the 2016 World Championshops] was racing locally in Belgian and not detected using a motor you would expect the UCI or Belgian Federation to at least test bikes.”

“For the Worlds, I was tested the morning of the race and bikes were tested in the pits during the event, since then, no doping tests were undertaken for any rider or bike scanning since the worlds.

“Athletes are racing largely on the ‘honour system’ when there aren’t any anti-doping tests carried out at the races. History has demonstrated that the ‘honour system’ isn’t enough.”

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Bike Pure goes on to question how fair play and integrity can be maintained at events without anti-doping measures, saying that riders could “very easily resort to using performance-enhancing drugs without punishment”, while also pointing out that there is no evidence to suggest that riders were doping at these races.

In response to the letter, WADA said that testing was the responsibility of the UCI and the Cycling-Anti Doping foundation.

“Testing strategies at international events are under the responsibility of the relevant International Sport Federations,” a WADA statement said.

“WADA has contacted the Cycling Anti-Doping Foundation (CADF) to discuss the matters raised in this letter. Until we hear from CADF, as you will no doubt understand, WADA is not in a position to comment further.”

The UCI is yet to provide a response to the letter.