The challenge began earlier this year with a few health scares.
In May Irene was diagnosed with type 2 diabetes. It was on a holiday in the South Island later that month celebrating her 60th birthday she suffered excruciating chest pains - a doctor recommended she get on a bike and improve her fitness.
Her husband Vic, a keen cyclist himself, didn't hesitate and went to My Bike in Whangarei to find a suitable cycle.
Kim and Kerry Reyburn ordered a bike and within a few weeks Irene was rolling out the door and on the way to improving not only her health but her self esteem. She quickly progressed from riding the length of her driveway without falling off to riding the open roads near the port and then some sections of the race circuit.
"About 2.5km was all I could handle for a start and I worked my way up to 13km," Irene said.
"It's not impossible to do something that you haven't done before and you are turning 60. I take every day as it comes and I don't let diabetes or heart problems rule my life."