Jens Voigt, one of professional cycling's most-popular figures, admits to concerns about what effect the Paris terrorist attacks will have on the sport.
The retired rider, now an in-demand TV commentator, said he had already thought about the issue before the weekend.
Events such as the Tour de France are renowned for being accessible to the public.
But that also creates massive security issues.
The problem first came to prominence two years ago with the Boston marathon bombings.
"Already last year, I had one or two thoughts about it," Voigt told AAP.
"If you're not completely ignorant, or really simple-minded, of course that has to occur to you - that has to cross your mind.
"Boston marathon - who would have thought?
"The Tour de France, it's a big event with millions of people on the side of the road."
Voigt is in Australia for this weeks's Tour On Stage nights in Sydney and Melbourne, where he will join commentator Phil Liggett and cyclists Simon Gerrans and Rohan Dennis to discuss the sport with fans.
Voigt said it was vital big cycling races struck the right balance between vigilance and enjoyment.
"You cannot let yourself be controlled by fear," he said.
"That would almost be like you're giving in.
"Part of the charm of our sport is that, yes, we are approachable - people can come and talk to us, look at us, chat to us.
"We don't charge entrance fees."
He noted the Tour de France was already taking extra security measures.
"Hopefully, we're finding the right balance," he said.
Voigt said even without security concerns, it was sometimes hard for riders to strike the right balance between interacting with fans and doing the job.
"It's about finding the right balance there of being approachable, but also thinking about the job you have to do in the next stage or the next race," he said.