Having to wear a helmet was holding many people back from cycling, Gummer said.
"A lot of people are very judgmental on people who might choose to not ride because of seemingly the most trivial of things. It could be helmet, hair, or it's just not comfortable. I think the biggest real reason is that in the end, wearing a helmet is essentially taking responsibility for a failure, an institutional failure to provide cycleways.
"It's like the worst way of providing safety when there are a multitude of other things that should come first."
Gummer said cycling "simply must be a viable part of the mix" to help fix transport issues.
He mentioned a study from 2007 in which researched Ian Walker rode in traffic and found drivers would travel about three and a half inches - or 8.5cm - closer to him when he was wearing a helmet than when he was not.
Another study in 2013 re-analysed Walker's records and concluded that helmet-wearing was not associated with vehicles passing closer to a cyclist.
Gummer said he personally chose not to wear a helmet in traffic because he believed it was safer, but did not want to tell other people they shouldn't.
"That's something that definitely warrants further research," he said.
Kiwis had "some great spaces to cycle" but it was not enough.
The risk to cyclists not wearing helmets is "actually incredibly low", he said.
"It's a very low-risk activity in the first place ... there are many, many more activities that other people engage in that are quite risky that don't require a helmet."
Climbing a ladder and being a pedestrian both carried risk as well, he said.
He said putting on a helmet couldn't not be easily compared to wearing a seatbelt as an easy way of protecting people from harm.
He said travelling on a bus was a similar level of risk to cycling, and there were no seatbelts on city buses.
Concussion expert Doug King said if people wanted to cycle without helmets they should pay for private healthcare when they injured themselves.
"I think if they're going to make things optional, why don't they start looking at maybe health care needs to be optional as well?" he said.
"You know, you don't wear a helmet, then you go privately and start paying for it."
King said helmets worked well to protect against skull fractures or penetrative injuries, though they didn't protect from concussions.
Wearing a helmet could prevent the patient from needing surgery or long-term rehabilitation, he said.
King believed the idea of removing the blanket ban was "misguided".
"People who want to take their helmets off and ride around, yeah it may feel nice with the air through their hair, but if they fall off and they get hit by a car, their skull's going to crack."
He said it was "sending a bad message" and kids would see the behaviour and try to emulate it.
Anyone wanting to attend this weekend's ride can gather at Wellington's Civic Square on Saturday at 2pm.