CLEVELAND, Ohio -- Renegade bicycle enthusiasts installed makeshift “bike lanes” on Detroit Avenue on the city's near West Side over the weekend, bringing to Cleveland the illegal practice of

The lanes consist of sometimes meandering strips of tape installed about four feet from the curb on both sides of the avenue between West 29th and West 32nd streets, with stenciled bike lane markings for "sharrows," or shared lanes, sprayed onto the pavement. Anonymous online commenters said the markings were sprayed chalk, not paint.

A steady stream of bicyclists used the lanes Monday afternoon, and motorists generally respected the stripes.

, head of Bike Cleveland, the city’s leading non-profit advocacy group for cyclists, posted a statement

on the organization’s website Monday saying that the group doesn't endorse guerrilla striping.

“It’s a liability issue if it’s not done right,” VanSickle said in a telephone interview.

But he said he could understand the frustration of bicycle enthusiasts over what he called the city’s failure to install bike lanes that it previously approved for Detroit Avenue in a timely manner.

The city unveiled a plan for the lanes last summer and said it would paint the lanes by springtime on both sides of Detroit Avenue for 1.7 miles from West 25th Street to Lake Avenue.

VanSickle said city officials have told him that the project, which was expected to cost up to $72,000, has been funded and that the city has received bids.

A handmade sign proclaimed the arrival of a new amenity for cyclists on Detroit Avenue Monday.

The filming of “Captain America: The Winter Soldier” on the Shoreway this spring may have delayed the installations on Detroit Avenue, which the city used as an alternative route for commuters, he said.

“Our understanding was that once the Shoreway opened up, they’d start the work on Detroit, but that was over two months ago,” VanSickle said.

Maureen Harper, the city's chief of communications, didn't respond directly to VanSickle's statements, but said in an email Monday evening that Cleveland "is actively working to increase the number of safe, well-planned bike lane miles in the city, including on Detroit Avenue. It's good for the city, encourages physical activity and lessens our community's dependence on the automobile."

She added that "random and unauthorized traffic signals, like the sharrows on Detroit Avenue, could cause significant harm and injury." She said the city will investigate the striping and "we will take appropriate action."

Van Sickle said

has been used by bicycle enthusiasts in cities across the country to demonstrate the benefit of adding lanes and sometimes has led to permanent bike lanes.

He likened the practice to "pop-up" experiments in urbanism, such as holding the Ingenuity Fest on the lower level of the Detroit-Superior Bridge.

VanSickle said the city could embrace pop-up demonstrations as a way to test the viability of ideas such as that of turning center lane medians on the city’s old streetcar routes into bike lanes.

In general, he said, Cleveland needs to speed up the delivery of bike lanes because the city’s population of cyclists is growing rapidly.

“From a bikeability perspective, we really need to make sure we’re prioritizing these projects and implementing them in a more timely manner,” he said.