Almost 90 of the Mrs. Doubtfire star's bikes, including a unicycle and a custom-made Dario Pegoretti-designed two-wheeler, were expected to fetch upwards of $200,000 (£164,000) as part of an online auction at Paddle 8.

But reports suggest the sale raised more than $600,000 (£492,000) for the Challenged Athletes Foundation and the Christopher and Dana Reeve Foundation - two of the tragic actor's favourite charities.

The bicycles were donated by Williams' children Zak, Zelda and Cody, who stated, "We hope these bikes will bring their new owners as much joy as riding them, and helping these causes, always brought him."

The Paddle 8 auction closed on 25 October (16) and highlight sales included a replica of a bike Robin's pal, Lance Armstrong, rode in the Tour de France and the late star's Master Pista, La Carrera with a custom design from artist Futura 2000, which went under the hammer for over $40,000 (£33,000).