Joshua Michael Young, a professional artist and competitive motorcycle rider and race car driver, was killed when his motorcycle crashed into an oncoming Mazda sedan on Barkers Lodge Road in Picton about 2.45pm.

Mr Young, aged in his 20s, was on a regular Sunday afternoon ride with his father, who was behind him on the scenic, winding road on Sydney's outskirts.

Fairfax Media understands Mr Young took a corner too fast and clipped the oncoming Mazda.

Craig Sheahan, who was one of the first on the scene, said he came across the man cradling his dying son on the side of the road.

Mr Sheahan was out for a motorcycle ride on Sunday afternoon and had chosen to take a shorter ride through Appin and Picton instead of to Port Botany.

After stopping for a drink and a rest in Picton, he said he had travelled only 800 metres along Barkers Lodge Road when he came across the accident and stopped to help.

"The rider was lying on the road and in a bad way," Mr Sheahan said, adding that "his father was there cradling his son".

"It was hectic as we waited for the emergency services to arrive.

"Things got worse, the rider was in need of CPR, I commenced, it seemed like an eternity till the ambulance arrived.

"I don't think it was going to end well for the rider and my ride home afterwards was very different, lots of time to think about things."

Mr Young, from the Fairfield area, was a keen motorcycle rider, car enthusiast, photographer, traveller and artist who sold his work under the name Losu.

He posted regularly in the Sydney Ducatista club for Ducati enthusiasts and enjoyed frequent weekend rides with his father.

Police said officers from Camden would prepare a report for the coroner.

The male driver of the Mazda sedan that collided with Mr Young was not injured.

Just half an hour after Mr Young's crash, three young Northern Beaches men were killed in a triple fatality on the Bells Line of Road at Bilpin.

After three days of psychedelic dance music, camping, drinking, dress ups and wild partying in the bush near Lithgow, four friends piled into their four-wheel-drive on Sunday afternoon.

Not yet halfway home from the Psyfari festival, their P-plate driver spun out of control and veered into oncoming traffic, crashing head on with a Subaru carrying a couple in their 80s.

Lachie Burleigh, 17, Ben Sawyer, 19, and Luke Shanahan, 21, were killed instantly.

Their P-plate driver, just 17 years old and from Freshwater, survived with minor injuries.

The elderly couple in the Subaru sedan also escaped with minor injuries.

So far this year, 235 people have been killed on the state's roads, 26 more than at the same time last year.

The disturbing spike prompted NSW Police to saturate roads and crash hot spots over the weekend.

However, nine people died in seven crashes after the operation began on Thursday.

Traffic and Highway Patrol Commander, Assistant Commissioner John Hartley, was both devastated and furious, blaming the "tragic loss of life" on poor driver behaviour and responsibility.

"With what have been perfect weather conditions, some road users are taking their driving for granted," he said on Monday.

"Over the past couple of days, officers have seen countless motorists showing a total lack of respect for other road users, and we are showing zero-tolerance to this type of behaviour."

Operation Saturation will run until September 28.