Adrian Collins, 42, was cycling to work when a car travelling about 70km/h came so close to his bike on a roundabout that he thought he was about to die.

"It was a very close shave," said Mr Collins, who records his rides using cameras on the back and front of his bike. They also measure the distance between him and a passing vehicle.

Shaken up: rider Adrian Collins. Credit:Steven Siewert

He downloads those that show a "blatantly conscious decision [by the motorist] to endanger the life of the rider".

Only 70 NSW motorists have been fined for driving too close to cyclists in the two years since the safe-passing rules were introduced in March 2016, NSW Police said. But about 10,000 drivers are charged with dangerous or negligent driving each year, and many of the fines applied to those driving too close to cyclists, police said.