The pair started local building company, Renaissance Homes, in 1996, and have been business partners as well as family members.

Andrew also dropped everything to be by Lud's side as he spent seven months in hospital recovering after a cycling accident in Canberra in early 2010 when he was made a quadriplegic.

Andrew is also now on an epic bike ride from Canberra to Humpty Doo just south of Darwin in honour of his father but also to raise money for spinal cord repair research and clinical trials through Project Edge and also for local charity Hartley Lifecare.

Andrew is attempting to do all 5450km off-road on a mountain bike, with his wife Jodie accompanying him in a support vehicle. He is covering all expenses, so every cent will go to his chosen causes.

The couple are due to arrive in Humpty Doo in May.

They were on rest day on Thursday when Andrew spoke to us Echuca in Victoria, already made very clear of the perils of attempting the trip cross-country rather than on bitumen.

On day two, he'd lost a saddlebag containing his tool kit travelling through the overgrown National Bicentennial Trail in the Snowy Mountains and three hours of backtracking failed to find it. (He does have a spare. And a spare for the spare.)

And he's also encountered "bindies from hell" near the Victorian town of Yarrawonga which flattened just about everything.

"I counted 26 in my tyres," he said, ruefully.

But Andrew remains upbeat about the trip and says his family has become stronger and more resilient as a result of his dad's accident. The family has a history of helping others. Renaissance Homes was a driving force in the Deakin Charity House Project which raised more than $2.2 million for local charities supporting people with disabilities.

Darwin - specifically Humpty Doo - was the chosen destination because it had been the scene of many happy family fishing trips and was home to some treasured friends who are helping with the fundraising bike ride.

"I think I said after dad's accident that if we got back to Darwin fishing I'd ride here and he did so I am," Andrew said.

Lud is also embracing life in his "new normal" as a quadriplegic.

He rode a hand cycle alongside Andrew for the first 10km of his trip. The bike is now being carried on the support vehicle across Australia and Lud will ride the last 15km alongside his son.

And he can't wait.

"I'm very, very proud of him," Lud said.

* To make a donation and learn more about Andrew's ride go to http://www.thespinetinglingride.com.au/pledge-now/