Motorcycle riders are at greatest risk of being killed or seriously injured in crashes that occur during the late afternoon, research has found.
Police today released the findings of a recent review of motorcycle crashes in WA between 1995 and 2014.
The review identified a strong trend that indicated fatal and serious injury motorcycle crashes on Monday to Thursday are most likely to occur between 3pm and 6pm.
An analysis of all 1447 fatal and serious injury motorcycle crashes found that 932 resulted in serious injury.
"They resulted in 524 fatalities and 984 people being seriously injured," police said.
The research found that the crashes on Fridays are most likely to occur between 6pm and 9pm, with 3pm to 6pm still prominent.
"Fatal and serious injury motorcycle crashes on weekends are spread out across a greater part of the day, however, this is likely due to the fact on weekdays there are early morning and afternoon commuter motorcycles on the road," police said.
"There are a number of possible reasons for this, including motorcycle riders travelling in peak commuting times [and] taking greater risks [and] other vehicle drivers being distracted."
Traffic and Emergency Response assistant commissioner Nick Anticich said many factors contributed to this trend, but the message to riders and motorists was clear: "If you are riding a motorcycle in the afternoon, history suggests you are at greater risk of being involved in a serious or fatal crash.
"Whether this is because you are tired from being at work, are in a rush to get home, or maybe you are passing other motorists that are tired or distracted, at the end of the day it is your life at risk, and you need to consider what you can do to stay safer," he said.
"Motorists travelling in the late afternoons also need to ensure they are alert, and not distracted.
"Driving a vehicle is a significant responsibility. One small moment of distraction or inattention can lead to devastating crashes."
Mr Anticich said that although in most cases the driver of a car would survive a crash involving a motorcycle, the psychological impact could last a lifetime.
Recent fatal and serious injury crashes involving motorcyclists made it clear that riders needed to change their mindset of believing they were bulletproof.
"Over the past couple of weeks we have seen too many motorcyclists involved in fatal and serious injury crashes," Mr Anticich said.
"Unfortunately, in many of the crashes, risky riding behaviour has been a factor in the crash, whether it be speeding, riding recklessly or dangerously and, of course, being under the influence of alcohol and/or drugs."
"Being a motorcyclist already makes you more vulnerable on the roads, so to add to that risk by conducting in more risky behaviour just doesn't make sense.
"You only have to look during peak hour to see motorcyclists lane-splitting at high speeds or weaving in and out of traffic in a dangerous manner."