The first 50km of the course was flat and the remainder of the race was a hilly circuit. While one of the 12 riders broke away, the four in McCallum's age group stayed together.
"There was a big crash in the younger women's age groups but the area had been cleaned up by the time we got there," McCallum recalled.
The Hawke's Bay Hospital clinical nurse specialist, who trained up to 15 hours each week before travelling to Perth, finished three seconds ahead of the third placegetter and eight seconds ahead of the fourth placegetter. While McCallum, who has been a competitive racer for 12 years, will give next year's world champs in France a miss she hasn't ruled out a return to world champs racing in the future.
She qualified for Perth with a second placing in her 84-strong age group at a Melbourne-hosted qualifying race in September last year. Her next major event will be the Cambridge-hosted New Zealand club nationals in April.
"Because they are in the North Island they will be good to do. There will be plenty of Ramblers events between now and then ... they're the best form of training," McCallum added.
Earlier this year McCallum raced for the Ramblers team which won the six-round Dynamo North Island Teams Classic Series. Her daughter Kirsty McCallum was also in the team.
The other TR Acupuncture and Massage Therapy-sponsored Hawke's Bay rider who
competed in Perth, Marg Porter, recorded a top 10 finish in her 45-49 years 19km time trial. She was one of several riders in her age group who came off her bike during a crash on the 142km road race.
While Porter completed the rest of the race, her hopes of a podium finish were dashed by the crash. Like McCallum, duty nurse manager Porter, was competing at her first world cycling championship.
Porter, who has been racing for 21 years, qualified for Perth with a sixth placing in a field of 67 at her Melbourne-hosted qualifying race last year. Porter completed the master 3 time trial-road race double at the Taradale-hosted club nationals last year.
She was hoping the Perth venue would prove to be a lucky venue for her as it was there where Porter recorded a top-15 finish in the 30-35 age group at the 2000 world triathlon championship.
Porter retired from triathlons in 2001 because cycling became such a big commitment.