A common stigma is that once you're diagnosed with dementia, you can no longer enjoy life.

But one man is proving the theory wrong – with a motorcycle and a dream.

Greg Kelly was diagnosed with younger onset dementia at the age of 59. Now, he's challenging the stigma and raising awareness the disease, which affects more than 60,000 people in New Zealand, by riding a Harley Davidson the length and breadth of Australia, New Zealand, and the US.

Greg, or ‘Kell' as he's known, has arrived in New Zealand in time for World Alzheimer's Awareness Month.

He commenced the Kiwi leg of ‘Kell's Ride' on the September 24 at John Andrew Ford in Auckland and will be continuing the ride throughout October, taking five weeks in total.

'I want to put a spotlight on this disease and raise awareness of younger onset dementia because this is not a disease just for the very old,” says Greg. 'There are people as young as 29 with it and it is the second highest killer in Australia and third highest in United States and New Zealand.”

Throughout the Kiwi leg of his journey, Greg is visiting each of the local Dementia New Zealand organisations, and raising money for them as well as awareness.

A particular highlight of the itinerary is a group ride from Mount Wellington Harley Davidson to Taupo on Saturday September 29 with members of the Harley Owners Group. And in between is two stops in Tauranga.

The plan is that Greg will stop at about midday at Ford Ultimate Group, 150 Hewletts Rd, before making another stop just down the road at East Coast Harley Davidson, 52 Hewletts Rd, around 1pm.

He welcomes anyone wanting to join the ride to support him at any point.

Greg's ride is also the subject of a short documentary, ‘Kell's Ride', made by Elizabeth McLeish of McLeish Film and Media.

It was recently chosen as one of two winners at the Sydney Lift Off Festival and was screened at the London Lift Off Festival as a result. Elizabeth is also creating a feature-length documentary, ‘Kell's Ride for a cure', which will cover his NZ and US journeys as well.

Although dementia is often thought of as an older person's disease, about five per cent of people with dementia are under the age of 65 when their symptoms begin to emerge.

'I was diagnosed with younger onset dementia in January 2016 at the age of 59. They told me I have had it for a number of years but was misdiagnosed with having depression back as far as 2009, as happens so many times with this disease. '

Since dementia is much less common in younger people, there are often challenges in getting a diagnosis, with GPs more likely to pin symptoms to conditions like depression or anxiety, as was the case with Greg.

Kell's Ride hopes to change that – to ensure that more people are aware of how younger onset dementia can affect.

Meanwhile another event kicking off today at the Mount Maunganui is doing its bit to help those with dementia.

Hundreds of people will be going the extra mile for the 60,000 people living with dementia in New Zealand with the annual Memory Walk in Mount Maunganui.

Alzheimers Tauranga/WBOP will be among thousands of Kiwis joining more than 20 walks throughout New Zealand in September as part of World Alzheimers Month.

The 3.5km Memory Walk will leave Coronation Park at 10am on Saturday, September 29.

All participants receive a purple Memory Walk t-shirt.