Creswell left Tauranga in 2004 to live overseas.
He had planned a "summer adventure" cycling in Britain and the US as a "last hurrah" before moving back to Tauranga. He started the TransAmerican Trail ride in Virginia on May 13 and had planned to finish in San Francisco on June 30, he said.
He was approaching the highest point of the route at Hoosier Pass in Colorado when an SUV crossed into the shoulder of the road and hit him from behind at 88km/h, he said.
"I have no recollection of the incident and came to in St Anthony Hospital, Denver, a few hours later," he said.
He later learned he had been airlifted off the mountain. Creswell's mother was in London when the crash happened and flew to Denver to be with him.
Doctors explained his crash could have caused long-term damage.
"But as a cyclist you accept that there are risks involved, and you can only do so much to minimise things like this happening," he said.
Creswell said his recovery had been slow.
"The brain bleed gives me headaches, vertigo and nausea and the broken ribs and vertebrae, and the associated back brace, makes for difficult sleep.
"But I am staying positive, and have been continually humbled by the kindness and generosity of everyone involved.
"I will make a full recovery and finish the ride at a later date."
Creswell said he was liable for the medical bills, even though the driver was insured and had been charged with careless driving causing injury, because cycle touring was excluded from travel insurance policies.
"I'm still liable for the $150k-plus medical bills until such a time as any settlement has been agreed between the driver's insurer, and the lawyer acting on my behalf," he said.
"This could take years."
Fellow cyclist Matt Boelter, who met Creswell during a stopover on the 6804km trail, had set up a Givealittle page set up to raise funds for Creswell's medical costs.
"In the short time that I was able to spend with Jay, it became abundantly clear to me that he is a compassionate and kind individual," said Boelter on the Givealittle page.
Boelter heard about the crash through social media and set up the fundraising page after noticing road signs while riding across Kansas about two weeks ago that said "Leave free for cyclists when passing".
The fundraising page had so far raised more than $8850.
Creswell said he had been overwhelmed with messages of support, donations and offers to help.
"It has been incredible, and a massive thanks goes out to all. I'm not angry, upset or bitter about it.
"It would have been nice rolling across the Golden Gate Bridge after 5000km of solo, but I know it will happen in the future and I'm lucky things didn't end up worse."
