"I wish I could have a word in his ear, and ask him what the hell he was thinking," she said.
"If he were in front of me now, my question for him would be 'do you value your life?' 'Do you value your passenger's life?' 'Did you have any consideration for anyone else?'
"He was bloody lucky - it could have been so much worse."
Ms Shaw said she was approaching a blind corner when the motorcyclist veered into her lane, "travelling at a million miles an hour."
She quickly swerved to the left to avoid hitting the motorcycle head on.
"At first, I thought, 'oh I've missed him.' But, I heard the crash - it made one hell of a bang."
Convinced of the worst possible outcome, Ms Shaw was distraught.
"I got out of the car, and I thought 'oh my God, I'm going to find two dead people.' I expected to find blood and guts everywhere. But, there they were, just sitting on the side of the road."
She said she didn't get to speak with the motorcyclist and passenger, who seemed "too shocked to do anything."
The impact of the collision left a deep gouge in the side of her car, and shredded both driver's side tyres. "The holes in my tyres were huge - the police couldn't believe it."
Following the crash, Ms Shaw was assisted by "fantastic" fire fighters from the Featherston Fire Brigade, as well as several passing motorcyclists and drivers, who helped direct traffic.
She found out she wasn't the only driver who had been troubled by motorcyclists' daredevil antics that day.
"There were heaps of them out - they would have been from a club. I met a truckie who said some of them had been 'passing him, driving like idiots' since Pahiatua. The whole thing was an accident waiting to happen."
Ms Shaw is waiting to hear if her insurance company can cover the damage to her car, and is having to borrow a friend's vehicle to drive to work.
She is most relieved her 10-year-old daughter was not in the car at the time - as she'd decided she'd rather stay at a friend's than come to Wellington.
Carterton Senior Constable Peter Cunningham said it is likely the motorcyclist will face dangerous driving charges - as he crossed double yellow lines to pass traffic. Mr Cunningham praised Ms Shaw's quick thinking, and said her swerving "saved the guy's life."
Ms Shaw has a some blunt advice for other motorcyclists: "Don't take unnecessary risks. Life's too precious - it's gone too soon."