All the victims were young men.
December was the only month in which a motorcyclist did not die.
Floral tributes and police markings in Heathridge stand as the latest reminder of a rider killed on local roads.
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READ NOWThe death last week of a 23-year-old Connolly motorcyclist, who was struck from behind by a 4WD on Hodges Drive near Caridean Street, was the fourth fatality between September and January.
Police have charged a Connolly man (39) with dangerous driving causing death over the January 3 crash in which three other cars were also damaged.
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He is due to face Joondalup Magistrates Court on January 30.
The incident continued a grim run of motorcycle rider fatalities on local roads since a 27-year-old man was killed in Ocean Reef on September 1.
Other fatal incidents happened in October and November.
On November 15, a 24-year-old man was killed when the motorcycle he was riding collided with a truck on Burns Beach Road in Joondalup.
A 17-year-old rider died after the unregistered motorcycle he was riding struck a car at a roundabout on Nicholas Road and Chatsworth Drive on October 20.
Local police have asked for safer behaviour from riders, advising against acts such as lane splitting where motorcyclists ride between cars to get to the front of traffic, particularly when vehicles are banked up.
But riders say it is safer for them to do so, rather than wait in line where they are at risk of being struck from behind.
A number of readers recently commented on the Weekender’s Facebook page in support of lane splitting, including one who said “lane splitting is safer than being a sitting target”.
Other readers were critical of motorcyclists’ behaviour.