Giving up is not part of who they are so, with total commitment and following a sharp training plan by Bicknell, they chased their goal of getting back in a New Zealand boat.
In February, they enjoyed their best medal haul at the nationals and made that team to Belarus.
"We have come a long way since a couple of years ago. Our goal is to make the A final, that is top nine in the world," Harker said.
"We have not had an under-23 men's K4 do that ever so that would be a really good start for this crew.
"We have a new coach (Frederic Loyer) who is also the open men's coach and he is looking to put together a crew for the next four years to head for the 2020 Tokyo Olympics."
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This will be Harker's fifth New Zealand selection and Waller's second.
"It has sort of been an eye-opener lately of the work we actually have to put in but it is good to see we are on the starting point now and getting into this squad has set us up for the next four years," Waller said.
"I'm in the back seat, Taris is in second seat, Kurtis Imrie is in the seat in front of me and Max Brown is leading the K4. They are both training together in Wellington.
"You all have to be in time. The one thing we have been focusing on lately is our leg drive because if you are pushing down at different times it can throw people out, especially if we get tired and our cores start to go."
Harker and Waller, who are both studying for a Diploma of Quantity Surveying at Bay of Plenty Polytechnic, have been training at Lake Karapiro with the rest of the New Zealand squad recently.
Their regular training ground is the Wairoa River, home to the BOP Canoe Club.
"We have really good water on the Wairoa. It is always flat, always calm with the only problem a bit of flow every now and then but it is consistent so speeds and times you can compare," Harker said. "It is pretty similar to the places I have trained overseas so it transitions pretty well."
During the summer months, Harker and Waller are volunteer lifeguards at the Omanu Surf Club.
They are grateful to the club and Chris Emmett for organising a recent quiz night to help raise funds for the expensive trip to Belarus.
"Omanu has always been helpful and we are thankful to everyone who turned up and all the businesses who donated spot prizes," Harker said.
"Tim has a GiveaLittle page to help him get there so it would be great if people could support him through that."
- givealittle.co.nz/cause/helptimgettoworlds