She cycled solo from Singapore to Bangkok last year to raise funds for the Breast Cancer Foundation. 

But freelance photographer Wendy Chan said this year's challenge is different. 

Besides physical endurance, she will also be tested mentally, something she feels cancer patients face daily.

And she plans to raise funds for cancer every year.

"I lost someone very close to me which led to me not being able to do anything except cycle, and that's when last year I decided to do something apart from just cycle but try to do something else, that was fund raising," she said.

Wendy's biggest challenge would be to continue cycling through the night and she is counting on friends to help her stay awake.

"I suspect for the next few hours I'll be alright because I just started, I'm quite fresh. But come probably six, seven o'clock, the breaks may get a lot more often. But I try not to stop for more than 5, 10 minutes at a time because it'll probably be quite difficult to be motivated to get back on the bike if i stop for any longer than that," she added.

But she'll keep her eye on the clock as her 24-hour attempt will end at 12 noon on Sunday.

All proceeds will go to the the Children's Cancer foundation which serves some 450 cancer patients and their families. - CNA