As Torontonians rethink the way they're using traffic-clogged roads, both drivers and cyclists cannot forget their responsibilities, a prominent cycling advocate says.

"Toronto has been a car city for a long time and, like many North American cities, we're shifting the way we're using our city streets because there's not enough room for more cars," Yvonne Bambrick, the author of The Urban Cycling Survival Guide, told CBC News. "More people are understanding the bicycle to be a fantastic form of urban transportation and they're using a bike to get around from A to B."

But doing that has proven dangerous lately.

Early Monday morning, a cyclist suffered serious injuries after being hit by a vehicle near Dundas and Parliament streets. On Sunday, three cyclists were struck in a space of four hours, police said.

Several dozen cyclists took part in what they called a "ghost ride" Tuesday evening to remember a 71-year-old cyclist who swerved into a parked van on July 5 while trying to avoid a turning car. He died of his injuries in hospital later that day.

Just before cycling to Dupont and Christie streets, where the collision happened, the group listened to a few speeches by bike advocates.

"We're here to celebrate the memory of a lost life. He could be right, he could be wrong. He's a cyclist, he's one of us and we need to pay homage," one man said. "Try and ride as slowly and respectfully as possible, and win the motorists over with kindness."

Paying our respects to the friends & family of the 71yr old man killed while riding last week. TY <a href="https://twitter.com/RespectTO">@RespectTO</a> <a href="https://twitter.com/hashtag/biketo?src=hash">#biketo</a> <a href="https://t.co/LnzHIyO3is">pic.twitter.com/LnzHIyO3is</a> —@CycleToronto

A white ghost bike was left at the accident scene as a memorial for the man who was killed.

"Collisions will happen" when trying to get around a big city, Bambrick said, but she urged cyclists and drivers to stay alert.

Cyclists need to "communicate your intentions, err on the side of caution, and read traffic around you" — but she didn't let drivers off the hook either.

"Drivers have got to take responsibility for their actions when they're behind the wheel," Bambrick said. "A lot of drivers still feel a tremendous amount of ownership when it comes to roads. If we could understand the value of our neighbours on bicycles and have a little more compassion and patience, we'd get along better."

Bambrick credited the city for working toward making Toronto more bike-friendly, pointing to council's decision last month to double the size of the cycling network. The plan will be rolled out over the next decade and cost about $16 million each year, eventually adding 525 kilometres to the city's cycling network.

"We have an expanded bike-share system and we have good leadership within the transportation department and within council," Bambrick said. "We've seen a shift. People are really starting to understand the value of the bicycle for the city.

"Torontonians ride bikes, we need to make it safer for them to do so."