A rare machine, the 1911 NSU 500cc single cylinder motorcycle will be one of the star attractions at the 22nd National Motorcycle Rally in Oamaru.
While Mr Green owns the motorcycle, he will be "the minder" for Mr Appleby when he rides it at the rally.
"He's more aerodynamic than me," Mr Green said.
The motorcycle has a chequered history, but spent many years as a static display in a Brazilian museum before being bought by Mr Green and his wife Sarah.
When they shifted from the UK to New Zealand in 2004, the NSU came with them, then eventually found a home at Appleby's Garage in Kurow when Mr Green bought the operation from Mr Appleby almost three years ago.
In the museum, while the motorcycle looked "aesthetically correct", it was not running.
About six months ago the two men started to make a real effort to get the motorcycle running for the rally.
About 95% of the parts were there when it was stripped, but those missing had to be made, including the spoked wheels.
The wheels, under order for years, finally arrived two weeks ago and last Saturday, the motorcycle was fired up for the first time and ridden around Kurow.
Its first proper trip was then to Hakataramea.
NSU motorcycles, in some of their components, were very advanced for their time.
Mr Green's is in the history books, owned by American Joshua Streiff and used by him in 1912 for a 6300km cross-American journey from San Francisco to New York and back again.
It will be one of 162 motorcycles taking part in the national rally, which is being hosted by the North Otago Vintage Car Club.
Motorcycles from 28 manufacturers will be represented - the largest number from Triumph - and include such other classic names as Norton, Velocette, Harley-Davidson, BSA and Indian.
Early Japanese marques will be there, along with lesser known brands such as Dneiper, Abingdon King Dick, Francis Barnett, Merkel and Silk.
This Saturday, entrants will gather at Takaro Park from 9am and start heading out from 10am, on their choice of three routes.
On Sunday, the motorcycles will be on public display in Takaro Park from 10am to 3.30pm for concours judging and teams' events.
An after-rally tour will be held on Monday.
