Sir Chris Hoy is aiming for a triumphant return from serious injury to international competition at the start of the World Cup Classics competition tonight at the Manchester Velodrome.

But Hoy will be competing against a background of widespread uncertainty as the Olympic authorities prepare to make changes that will deprive some of Britain’s top Olympic medal-winners of the chance to compete in their best events at the London 2012 Games.

There are serious losers — including Bradley Wiggins and Rebecca Romero — in the equality reforms proposed by the UCI, cycling’s world governing body that could be rubber-stamped by the IOC in December. The authorities want to give women an equal number of medal-winning races to the men but with competitions capped at ten track events, five for each gender.

That means a chance for Victoria Pendleton to go for medals in three events for the first time. But Romero and Wiggins may be unable to defend their individual pursuit gold medals. Romero has signalled her intention to switch to road cycling and Wiggins could be lost to road racing after an outstanding season that included winning fourth place in the Tour de France.

Pendleton has welcomed the chance to cycle for three Olympic golds. “Until the IOC put their stamp of approval on it, I am not counting my chickens,” she said.

Along with Hoy — who is taking on four events in Manchester in his first international outing since a dreadful crash in Copenhagen in February — Pendleton will be one of the busiest cyclists this weekend as Team GB attempt to revive the aura of invincibility that came with winning 14 medals in Beijing.