A cyclist who recorded and posted a road-rage incident online in which he was attacked by a van driver says he now regrets the way the motorist has been subjected to a campaign of abusive calls and emails.

Stephen Perrin is one of a burgeoning number of cyclists who, fed up with daily run-ins with drivers, has taken to wearing a camera on his cycling helmet. But he has now appealed for people to leave the man involved alone.

"It's the modern version of being put in the stocks," said Perrin, who was knocked off his bike and punched repeatedly earlier this month. The driver was apparently infuriated by the cyclist for sounding his air horn after Perrin claimed he had been "cut up" for "giving parked cars room".

"I put the video online because it needs to be seen, but the grief he and his family have got since from trolls and the like disgusts me," he said.

Despite Perrin recording the altercation in a Birmingham street, police refused to prosecute the driver, who was identified by local people. Perrin also posted the car registration number on the Birmingham Cyclist website.

Former Olympic champion Chris Boardman saw the video and passed on the link to his 80,000 followers on Twitter, which led to the situation "getting out of hand", according to Perrin.

He added: "The driver has a small business and I don't want to see him run out of town because of the abuse he's getting. Obviously what he did that day was his fault and I do feel there should have been criminal consequences for it, but a few idiots online always take things too far."

Sales of cycling-helmet cameras, which can cost up to £500, have soared and the number of road-rage incidents appearing on YouTube and other websites is growing. "I drive and cycle," said Perrin, a factory worker from the south of Birmingham. "I make mistakes on the road, we all do, but when I'm in my car it's a big metal box that can take a couple of bumps. On a bike it's flesh and bone. I got a camera for my own security."

A recent study in Australia looking at cycle-camera footage showed motorists were responsible for 87% of accidents or near-misses with cyclists, mainly due to lack of driver awareness.

Joe Williams, a spokesman for the cycling lobby group Sustrans, said: "The boom in helmet cams is a real symptom of the safety issues out there that we are hearing about again and again. It says much about the lack of a culture of mutual respect that people feel they have to protect themselves in this way.

"Too many people are dying on our roads. Everyone has a right to use our roads – motorists, cyclists and pedestrians. Safety is one of the main reasons people don't pick up their bikes with any confidence. People see roads as dangerous."

Williams called for police to act in cases such as Perrin's where there was video evidence.

A study commissioned by a car insurance company this weekend suggested that drivers fail to see 22% of cyclists on the road in clear view of their vehicle. Direct Line used revolutionary eye-tracking technology to establish that motorists who used satnavs were even less likely to spot a cyclist than those who did not. Some 24% of cyclists were "invisible" to drivers who used a satnav, while the younger the driver, the more likely they were not to spot a cyclist – 31% of cyclists were not seen by motorists aged 20-29, compared with 21% by those aged 50-59.

The corresponding figures for motorcyclists were also poor, with 15% not seen by motorists. By contrast, drivers spotted all but 4% of pedestrians who stepped into the road without using a crossing. The problem was worse in London, where 30% of cyclists were "invisible". A Direct Line spokesperson, Vicky Bristow, described the results as "frightening" and called for the government to take action. She said: "Encouraging all road users to be extra vigilant will improve road safety, but tackling an issue of this scale requires top-down change."

It allowed researchers to establish exactly where drivers directed their vision, which was often at clouds, buildings and passersby.In 2011-12, 2,660 cyclists were seriously injured on the roads, the highest number this century, while deaths hit a five-year high of 122. Of those, 106 are known to have been due to a collision with a motor vehicle.