And now they're turning the issue of safety into a street fight.
Members of a group called "Right of Way" decided to spray paint fake bike lanes along six blocks in Midtown.
They made their point with spray paint and stencils over the weekend.
Some people call them bike vigilantes, but these activists say they are sending a message.
"This bike lane is not going to survive," said Keegan Stephan, a Right of Way bike activist. "We know it's not a proper bike lane, this is a statement."
Especially on West 49th and Sixth, where they say a bike lane merging into traffic led to an altercation last month.
Afterwards, a cabbie lurched forward, severing a British tourist's leg, and so now there are six different blocks of Right of Way's stenciled symbol.
The group is taking to the streets unauthorized, and leaving their mark.
As you're riding up Sixth Avenue, unless you're some sort of a bike lane expert, you would never be able to tell that Right of Way's symbol is not a legal bike lane.
Best case scenario: the group hopes to raise awareness about traffic safety.
In Seattle, a similar action by a rogue bike group led that city to implement the unauthorized bike lanes and tweak them.
In New York, the city's D.O.T. so far says they'll inspect the area and take appropriate action. But so far this 'road test' continues.
