A field of 40 people were on the last leg of Opera2Parliament to raise money and awareness of lymphoma when the mishap occurred.

Chief executive of Lymphoma Australia Sharon Millman said the injured rider was not seriously hurt, but was taken to the Canberra Hospital for observations.

''I think she was more shook up than anything else,'' she said.

The event started last year after 25-year-old Jovan Pejic and his brother and a friend decided to ride from Sydney to Canberra purely for the challenge.

Just days before the ride, Mr Pejic was diagnosed with stage 3 follicular non-Hodgkin lymphoma, and decided to cancel the ride.

''My brother Nikola said we should not let this change our plans and we should try to turn it into a good cause,'' Mr Pejic said.

An elite judo athlete, Mr Pejic said he was accustomed to knocks and had earlier disregarded a lump in his groin discovered while showering.

''To be honest, I forgot about it for a couple of months, because I thought it was going to disappear by itself, because I was young and really fit. Cancer was the last thing on my mind,'' he said.

''About two months later I came across the lump and it seemed to be a little bit bigger and was noticeable on the surface of the skin. I went to check it out, not thinking anything of it really; that's when the GP couldn't tell me what it was and sent me for an ultra-sound.''

Ms Millman said someone was diagnosed with lymphoma in Australia every two hours.

''We don't know very much about the cancer, about what causes lymphoma; we do know it is one of the fastest growing cancers. Most people in Australia don't know the signs and symptoms, less than 20 per cent would know the signs and symptoms,'' she said.

''Someone dies of lymphoma every six hours in Australia, it is actually higher than what we lose to skin cancer.''

Mr Pejic completed radiation in December, is in remission and has raised more than $9000 of an overall total of about $50,000 this year.

''The average survival rate for this cancer, I was told, is about 15 years, but the doctors are hoping with the treatment I was given that won't be the case, it will be for much longer.''

Mr Pejic expects the number of riders, who started on Friday and stayed overnight at Mittagong and Goulburn, will build in the symbolic journey in coming years.

''There is rolling hills, there's ups and downs and everything lymphoma patients go through as well through their diagnosis,'' he said.

''In the first days it is quite challenging, because you go from sitting down for 40 hours a week to riding all day, sitting on a tiny little seat. It is a bit of shock to your body in the beginning. Your body gets to adjust on the second day and it is a lot more enjoyable from there on in.''