CYCLING - BMX: Australia's Caroline Buchanan has won gold at the UCI BMX world championships in Auckland to put the demons of her London Olympics campaign behind her. And Lauren Reynolds won silver.

Buchanan clocked a time of 25.506sec in a dramatic final at Vector Arena to beat home compatriot Lauren Reynolds by 1.296sec while Frenchwoman Manon Valentino bagged bronze.

For the victorious 22-year-old Canberran, it was some redemption for a below-par Olympics campaign last year.

She entered the event as the world No.1-ranked women's BMX rider but was in tears when she finished fifth.

On Sunday, she started in the box next to Olympic champion Mariana Pajon and cut her off in the first straight to take the Colombian out of contention.

"It's the one that I wanted since I was eight years old," said Buchanan.

"I wasn't 100 per cent over what happened at the Olympic Games until now.

"I had first lane choice at London.

"I took lane three and blew it. I made sure I didn't make the same mistake again and went for lane one this time around."

"When it comes to finals you've got to release the mongrel and get aggressive.

In the men's event, Englishman Liam Phillips made the most of his opportunities after many of the heavy hitters had eliminated one another in a quarter-final crash-fest.

In the final, he led from start to finish in a time of 23.280sec to claim gold by only 0.212sec ahead of New Zealand's Marc Willers.

German Luis Brethauer took bronze.

Of the Australians, Joshua Callan was fifth in the final but Sam Willoughby failed to qualify for the decider after running into a rival rider in the lead-up races.

AAP