It is the first time the tour has run since it was abruptly suspended in 2007 after a frightening crash between a group of female riders and a four-wheel-drive.

The riders were racing on Cotter Road when a clash of wheels caused the whole group to fall.

One rider, Sydney triathlete Jenny McKenna, was thrown from her bike into the path of the oncoming vehicle and suffered severe brain damage.

McKenna's father John, who is now her full-time carer, said that while the accident was a case of horrible timing and bad luck, it could have been prevented.

''If the road was closed this wouldn't have happened,'' he said.

''If the road isn't closed there's a propensity for a similar thing to happen and I wouldn't wish that on anybody.''

After a year's absence due to organisational issues, the Tour is back and race director Peter Gough said that while there would be a strong emphasis on safety no roads would be closed.

Instead, temporary speed limits of 60km/h would be imposed on all roads used in the race and police would control traffic via check points on Brindabella and Uriarra roads.

''We will be talking to every driver that enters the course and telling them to be aware,'' Gough said. ''Hopefully it's not too inconvenient, there might be a few delays but we ask for drivers to be patient.''

The Canberra Tour is part of the national road cycling series and the course, which winds through Uriarra, the Cotter and towards the Brindabellas, is considered one of the toughest in Australia.

President of the Canberra Cycling Club Jason Parkes said the race attracted a strong field of riders because of the challenge it presented.

''It's a hard race because it is so hilly but it's not just for A grade, anyone can come along and have a go ... a lot of people come to challenge themselves because it's one of the more difficult tours,'' Parkes said.