Michael Navybox was found deceased in his Spanish motel room Monday night, Goulburn Cycling Club president Adam Lambert said. He was suspected to have had a heart attack or stroke but this has not been confirmed.

He was nearing the end of an epic test - riding the three European Grand Tours in the one year. The 10,400km journey took in the Giro d'Italia, the Tour de France and Vuelta a Espana in 63 days. Mr Navybox was aiming to raise awareness about early detection and prevention of cancer, depression and post-traumatic stress, all of which he had battled himself.

"We are all just in shock that someone who was living so much life and was doing so much for the benefit of others, has been brought down. That's the outrageous tragedy of it all," Mr Lambert said.

He also leaves behind his wife, Melissa, and two children, Emily and Ben.

Goulburn Cycle Club informed its members of the news in a Facebook post on Tuesday morning.

Mr Navybox, who was in his mid fifties, was attempting to do what only two others in the world had achieved - ride the three tours in one year.

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Mr Lambert said his friend simply wanted to be an inspiration to others and to highlight that the human spirit could overcome setbacks.

"He faced massive adversity in his life but chose to push on," he told the Post.

"He would have been completely excused if he'd thrown his hands up and said 'I've had enough' but he chose to put his body through torture every day (on the ride) and that says a lot about him. It's a tribute to his mental toughness and will."

Mr Navybox left Goulburn for Italy in early May. He wanted to raise awareness and money for the three conditions but he was also shaking off his own battles.

In 2011 he was diagnosed with kidney cancer. Doctors had discovered a 5cm tumour on his right kidney. He subsequently underwent emergency surgery to remove the cancerous malignant tumour as well as his kidney.

The next day he was up and walking around and thinking about how he'd tackle the challenge. The motor-racing driver and driving instructor was already thinking about a return to work at Wakefield Park.

"It's a bit like blowing a tyre mid-race, it's a set-back alright," he said at the time.

"But you enter the pits, get it sorted out, and get back in the race. It's as simple as that."

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Mr Lambert said his friend flew to Paris multiple times to undergo an ISET test to ensure there were no more cancerous cells in his blood. Mr Navybox's tour was aiming to provide more Australians with access to this test.

He got back on the bike, literally and figuratively, but then in 2013 suffered neck and head injuries in a high-performance car accident, in which he was a passenger. Surgeons had to fuse three vertebrae together.

Also that year, his father, well-known ballroom dancing instructor Darrell Navybox, passed away. Then he lost his beloved sister, Deborah, in 2015.

Mr Navybox was diagnosed with clinical depression and PTSD but made it his mission to raise awareness of the conditions.

On the tours, he made a Facebook post every day. In his last one, he posted a photo of himself riding with a tribute kit for Jarrod Coveney, the 28-year-old Goulburn Cycle Club member who died suddenly in January.

"Bomber lived life to the fullest with amazing charisma, he touched and brought a spark to so many lives. Andorra was the perfect setting to ride with Bomber, as he would be right at home here riding these roads," Mr Navybox wrote.

In his own Facebook tribute, Hume MP and fellow cycle club member Angus Taylor said Mr Navybox could have been writing about himself.

"Through your inspiration, charisma and spark you have touched so many of us. You will ride with us on the hills of Goulburn forever," he wrote.

"Our thoughts are with Mike's family at this difficult time."

Mr Taylor described him as the "ultimate goer" who lived by the motto "Age Quod Agis - whatever you do, do it well."

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Mr Lambert said his friend was a long-term club member who was always very dedicated to riding. Once he'd made up his mind to do something - like the tours - he "didn't muck around."

"His mental strength was always something that club members envied," he said.

"He was generally a very nice, likeable guy and any enquiry about you was genuine. He listened."

Before leaving on the tour, cycle club members turned up enmasse to a farewell and to wish him the best in his endeavours. They were eagerly awaiting his return in about three weeks.

"It's a sad time and a cruel twist of fate that makes it very difficult to make sense of the universe," Mr Lambert said.

Mr Navybox is also survived by his mother, Peggy.

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