ROAD safety experts say the growing popularity of motorcycles and the recovery in the economy are behind the spike in the state's road toll.

The director of the NSW Government's Centre for Road Safety, Soames Job, said a major cause of the sharp increase in the road toll - up from 321 deaths in 2008 to 415 deaths in 2009, as of Wednesday - was the increase in ''two-wheel vehicles''.

He said that as of midnight on Thursday, motorcycle fatalities stood at 65 for 2009, compared with 44 fatalities for the same time last year, while the number of deaths of bicycle riders had more than doubled in the same period, from six to 14.

The Minister for Transport, David Campbell, said that following the steep rise this year - even before the traditional Christmas party season begins - the Government held an emergency road safety meeting and implemented an action plan. It included increasing the number of highway patrol officers and deploying them in known black spots and introducing hard-line sanctions for high-level speeding offences.

''This year's road toll has already surpassed last year's total and that is simply not good enough,'' he told the Herald.

Two children, aged 11 and 15, were killed and two teenagers critically injured on the mid-North Coast late on Thursday night after the car they were travelling in crashed into a power pole at high speed.

Police said a 16-year-old female learner driver had taken the 2004 model Mazda 3 sedan out unsupervised.

Senior Constable Jason Bentley, of the Port Macquarie Crash Unit, said: ''They were travelling at high speed and overtaking other cars … and there were a lot of witnesses. She panicked as she was overtaking the cars and lost control.''

Dr Job said motorcyclists and cyclists were especially at risk riding on sharp curves on country roads or at busy city intersections. He has raised the possibility of new laws requiring the riders of mopeds and motor scooters to wear protective clothing in addition to helmets.

In January, the Federal Chamber of Automotive Industries reported that motorcycle sales had ''soared to record levels''.

Dr Stuart Newstead, a senior researcher at Monash University's Accident Research Centre, said motorcycles had increased in popularity because of traffic congestion in cities such as Sydney, easier parking and drivers wanting vehicles that were cheaper to run and, in many cases, created lower carbon emissions. But with their popularity came a 25 per cent increase in motorcycle fatalities since 2004.

Dr Newstead also suggested higher overall road tolls were often related to growing affluence because the wealthier people felt, the more discretionary trips they made in their cars. Economic growth also meant more trucks carting goods were on the road, increasing motorists' exposure to risk of an accident.

with Glenda Kwek