"On a tandem, I'm the captain and Tina is the stoker," explains Sid.
Adds Tina: "I've got to have this feel if he's going right or left and absolutely trust him. I do exactly as he does. I'd just trust him with everything, and he would warn me if he was going off the road because I can't see - I can only look sideways."
The couple kept a blog of their ride, which they called Two Old Farts on a Tandem, and much of it relates to their favourite food, carrot cake.
Inspired by Major Tom in the UK who used his walker during lockdown to raise money for the NHS, Sid bought a tandem bike and added an electronic motor when his wife found it difficult to ride a bike on her own.
They're planning to visit rest homes to inspire elderly folk to keep active, whatever they're capable of.
Their bike was an e-bike but had to be kept at its lowest power to go the longer distances.
Tina says Sid's lack of pressure to keep going gave her confidence to take the ride "chunk by chunk".
"This man of mine said to me 'if you at any point can't go on, we stop, we're not here to prove anything. This is an adventure, we will go as far as we can.'
"My word of honour, I love him more after this gruelling trip, because those long hills, they go for kilometres and it's taken everything out of us and at the top you just want to embrace the achievement. That made such a bond."
As for what Sid thinks of his wife's achievement: "She never once complained".
"She never once asked me to stop for a rest or anything. When we stopped she accepted it, and from my experience a trip like this could either end up with you loving your partner more or a divorce."
They did stop though - to take a closer look at an unusual plant, to notice the unusual cloud formations, or the animals and the birds.
"When the wind is coming up you feel it, you are just part of nature. I experienced nature like I've never experienced nature," says Tina.
"There were stunning farms and even through the cities I'd marvel at the houses and gardens."
Did she pedal too?
Sid laughs and replies: "I asked that sometimes too. When you're in the front you're aware of it."
Sid Giliomee changes another tyre on his tandem trip from Waihi to Wellington. Photo / Supplied
The bike had 170kg on its back wheel, which led to three tyres being changed because of wear and tear, and a parcel sent home from Tokoroa when they realised they really didn't need a lot of what they'd packed.
Both on their second marriage, they met and married in 1996 and moved from South Africa to New Zealand with a huge amount of travel along the way, including all of their home country, neighbouring African nations, China and India.
When Sid retired from his job as a learning development manager for Nokia in Wellington, the couple moved to the Coromandel.
They had promised themselves they'd retire after falling in love with the "turquoise waters" on a cycle near Port Jackson.
Waihi is now home.
"Family isn't necessarily all family, it's friends as well," says Sid.
"Many of our friends are younger, and they all come to our patch in Waihi with their caravans, so we built extra showers and other things for their visits. We have a brai [barbecue] and drinks around the firepot. We're not born kiwi but became Kiwi through the acceptance of the people. Waihi embraced us."
Their journey to Wellington on Sid's custom-built $3600 tandem also proved how hospitable Kiwis are everywhere.
Their strategy was to ride from 6.30am until lunch, where they'd park up at a cafe, charge the bike batteries and their bellies, and get back on the bike after a good rest, usually around 3pm.
Countless carrot cakes later, they've not lost weight but only gained a little.
"I am like a donkey with a carrot," says Tina. "I think it was every day a carrot cake."
