The event — which will be back for a 21st year — has raised over $2.5million for local charities since its inception.
Taking place over three days, the ride would cover 365km, from Timaru to Tekapo to Kurow and back to Timaru.
Organiser Neville King said in previous years they had made about $100,000; however, they were "very aware" that they might not make that much this year.
He said for that reason, they hoped to drum up more entrants.
Mr King said for people wanting to dip their toe in, they could come along to the next training ride and see if they liked it.
He said — unlike their very first charity ride — nowadays some people used e-bikes.
Mr King would be taking part for the 14th year in a row, which was not unusual as he said one of the initial organisers had been in every single ride.
"He sees the benefit for the community, and he wants to see the event go as long as possible."
But he suspected he also enjoyed the banter.
"There is always good banter there."
People who ended up on the rides came from all walks of life.
He said one year they had obstetricians, surgeons and general practitioners through to a funeral director, which had been the subject of much amusement, with many quips about cyclists being covered for all medical emergencies.
The training ride would take place from 8.30am on Sunday, meeting at Aorangi Stadium.
