DIY Bike Route

Contrail_main00.jpgA photo simulation of Contrail in action. Image: Jessi Pervola and Studio Gelardi.

Ever wonder which paths cyclists naturally take through the city? Not satisfied with the location or extent of designated bike lanes? Feel like other street users are quick to dismiss the presence of cyclists?

"Contrail" is a design concept that enables cyclists to increase their visibility to cars, pedestrians, and each other. Conceived by Pepin Gelardi and Teresa Herrmann, this frame-mounted device would allow cyclists to make their mark on the street with faint lines of chalk. The rear wheel spins a smooth trail of color onto the pavement as the bike whizzes along.

Contrail leaves an impression based on the cumulative movements of many
cyclists over time (a more lasting variation on the BYO bike lane concept employed by the laser-projected LightLane). Its provocative visual language lies somewhere between sky
calligraphy, temporary street graffiti, and overlapping footprints in
the snow.

Gelardi and Herrmann proposed Contrail for the Power to the Pedal competition, and are currently developing a prototype. They envision "a new cycle of biking participation" in which the criss-crossing chalk ribbons would pique curiosity, identify more popular routes, and inspire more cyclists to hit the road.

  • This seems really cool. I have a couple of concerns though.

    1. How exactly does this work? it looks like their is chalk on the tire? and will it effect braking power of the bike?

    2. People have been fined for use of chalk in public space calling it graffiti, of recent memory a little girl in Brooklyn was issued a ticket for drawing on her stoop.

    I love the idea of leaving your mark on the streets you ride though.

  • cr

    Seems like a terrible idea. Will be confusing for drivers who are already overly befuddled and inattentive. Also, who wants to be followed? I’m willing to bet these get banned before they even hit the mass market.

  • It’s absolutely brilliant. I would love to see that around. I’d like to see where bikes go.

    In Seattle it’s pretty much dry through July and August, so maybe the thing to do would be to get everybody to do starting in July.

  • bb

    Anyone notice the helmet strapped to the waist?

  • I love this. It’s like drawing in the streets. However, I fear Gary is right…NYPD would have a field day.

  • jonesy

    cool in concept, but seriously: how many bike lanes, markers, mash-ups, do we need? part of the sheer joy of biking is its creativity, that you can take different routes, that you can have solitary time if you want and little tricks that make your commute much faster because you know about it. why share it, why designate more lanes and separation? i love the idea of more bikes, but i’m very anti-bikelanes, and this even more so: i want the nonseparated roads that you’ve written about before in other cities. no markers, no lanes, no nothing. the more we have segregated lanes (ie grand) the more we’re diverted, our street power diminished, the transgressive part of biking shunted aside…

  • Clarence Eckerson

    To each his own, interesting, very beautiful, but not something I would personally hanker to do. As it is, I can barely find the time to remember to bring my lock and put on a red blinky. Remembering to have to fill up with chalk before I ride? A non-starter…

  • PS

    More data is always a good thing.

    When riding my bike for transportation (and not for leisure), I seek out bike lanes and routes frequently used by cyclists because drivers who regularly use those routes are accustomed to sharing the road with cyclists.

    Contrails would help both cyclists and drivers alike along these heavily-cycled routes. Cyclists unaware of the route could more easily find it and drivers unaccustomed to it would be alerted to the greater likelihood of coming across a cyclist along it.

    To respond to the concerns raised by some of the other commenters…

    gary, the laws as currently written could prove to be problematic, so some sort of lobbying/policy work would have to precede the release of this product.

    cr, distracted drivers are typically preoccupied with things happening inside their cars–a phone call, a fussing child, a loud radio, an inadequately rouged cheek–and are already not giving adequate attention to the world beyond their windscreen. I doubt some unobtrusive lines on the edge of the road are going to make it much worse.

    jonesy, nothing would compel you to follow the contrails or leave ones of your own if you didn’t want to. While I agree that less formally delineated bike routes should be our ultimate goal, I think that well-defined bike lanes are an important first step to take in our car-centric country because they get drivers accustomed to sharing the road with cyclists and they make bicycle transportation more appealing to novice urban cyclists.

  • Zak

    “Its provocative visual language lies somewhere between sky calligraphy, temporary street graffiti, and overlapping footprints in the snow.” This is so lovely. I think of the fading tire prints that draw from puddles after a rain and to imagine those extending, unfading and multi-colored is a real delight. I think I would also feel the safety of community even when riding alone if I could see the prism contrails braiding along on the road before me.

  • Jonesy, I agree with much of what you said, and normally chalk contrail would not be my thing, but consider the times when riding on a particularly crap day, and seeing all the previous riders tracks frozen in slush, (that always lifts me up), it shows there are other riders/idiots out here. Also, in the theme of disliking bikelanes, I wonder that leaving a trail of how you handled a street hazard i.e. Dumpters in bike lanes or a section of road that always requires taking the lane to safely transit the area. I am not trying to sell you one though. And in terms of the NYPD and the illegality of chalk: The bike rider who got arrested during the RNC was writing messages-on the sidewalk I’d I am not mistaken.

  • Sorry, iPhones are just not the tool for posting comments…

  • Tom

    I plan on developing a DIY of this concept using sidewalk chalk and posting it on I hope to have it done in the next few weeks, search for bikewriting as I’ll make that one of the tags.

  • =v= Some years back a federal judge on the West Coast ruled that chalk-painting was protected by the First Amendment. This had something to do with why, with the police right there watching us, we could use tempera paint to make a bright green bike lane at San Francisco’s notorious Octavia and Market intersection (and bike through it, leaving bright green “contrails”).

    The NYPD has shown contempt for the Constitution and federal rulings, as we’ve seen in the case with the little girl in Brooklyn and even more dramatically with the on-camera arrest of Josh Kinberg while he was being interviewed by Ron Reagan Jr. We (the beleaguered bicycle community) have taken the NYPD to court again and again to get them to respect our rights.

  • Doing something similar with phones / GPS would be cool and could potentially be easy with the tech that’s available now.

  • Dug

    I agree that the phone option would be better. The visuals are cool from an artistic standpoint. But, they do nothing but add pollution and obstruct the view of others. While these effects are minimal, they take away from the environmentally friendly aspect of cycling. Cycling has enough fads. Lets stick to the basics and expand on an already great idea.

  • Hugh Butler

    I would like to have a “contrail” for my grandson’s tricycle. He would love it.

  • Revital Faigel

    Hi gideon. are you from jerusalem ?? are you familiar with Shelomo trokman ? arie Negler from you’re old HAVORAT AEVEN “regirung”.
    Please contact me at my E-mail. i’ll really appreciate it..


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