The Centre for Accident Research and Road Safety (CARS) in Queensland says motorbike accidents are more common on the weekend because more people ride then.
Four motorcyclists have died on south-east Queensland's roads since yesterday.
The centre's Professor Narelle Haworth says several factors explain the increase in motorbike accidents.
"I think that motorcycling has become a lot more popular, and consequently we're getting a lot more crashes," she said.
"And certainly there are a lot of people who are riding out there who don't have a lot of experience.
"Also, there's the issue of just the high severity of crashes when they do occur involving motorcycles."
The State Government says new motorcycle laws coming into force next month will improve road safety.
Transport Minister John Mickel says from July 1, all new licence holders will be limited to 250cc bikes, and passengers must be older than eight years.
"Part of our campaign is to send out to some 600,000 registered motorbike users a direct mail of our motorcycle safety kit to reinforce a campaign that has been running for sometime now," he said.
