"I think the idea that you have got to dress up like a bloody spaceman in order to ride a bike is just completely potty," said Norris to a BBC reporter in York.
The Royal Society for the Prevention of Accidents (ROSPA) said Norris should be setting a "better example."
The former Conservative transport minister was responsible for pushing through the National Cycle Strategy, a scheme later adopted by New Labour. He's also a former mayoral candidate for London and sits on the board of Jarvis, the engineering firm responsible for track safety at Potters Bar, scene of the recent rail crash.
He told the BBC reporter: "I never wear a helmet for the same reason I never wear lycra.
I think the idea that you have got to dress up like a bloody spaceman in order to ride a bike is just completely potty. You should be looking at it [cycling] as something that normal, fat, middle-aged men like me do. If you are a young child you wear a helmet. My little four-year-old does. I don't.
"I am big enough and ugly enough to know what I am doing and I am not going to treat myself as some kind of martian in order to do something which I have got every right to do."
Thanks to http://www.bikemagic.com for the tip-off