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Study: Half of Portland bike riders don’t know how to trigger green lights

Posted by on November 13th, 2013 at 9:57 am

Signal aids and innovation-3

The place to place the wheels.
(Image by J.Maus/BikePortland)

The pavement marking to the right, which is supposed to tell people where to place the wheels of their bike to trigger a green light, is illegible to about half of Portland bikers, a new study (PDF) finds.

Even worse: Those figures don’t include many people who rarely ride, suggesting that interminable red lights are a particular burden on new bike riders.

Stefan Bussey, a PSU civil engineering student who conducted the survey, said he came up with the idea when he noticed that people ahead of him at the long Seven Corners traffic signals on Southeast Division would regularly stop a few feet away from the traffic signal stencil.

“It would happen three or four times a week,” Bussey said.

Bussey’s research confirmed it: even in Portland, about 55 percent of bicycle riders surveyed don’t know the meaning of the pavement marking.

The small, unlabeled slice represents 2 percent
of bike riders who thought it meant “bikes allowed.”
Photo from Bussey, graph by BikePortland)

Portlanders seem to be doing better than Floridians. A study of 68 Tallahassee residents last year found that zero of them knew what the above stencil, which is a national standard road marking, means.

The Portland findings are based on analysis of 302 hours of video footage and a combination of 227 in-person and online surveys. Of the survey respondents, 65 percent said they ride a bicycle at least three times a week.

More than a third of those said they’d wait for a traffic light by standing within 10 feet of the curb, even at an intersection with a marked bike detector near the middle of the street. Survey data also suggested those riders were motivated by a desire to stay “out of the way” of traffic, Bussey said — suggesting that red lights are a particular burden to less experienced riders.

A still from Bussey’s video observations.

From his video footage, Bussey found that explanatory road signs and green coloring behind the stencils can both draw attention better than white stencils alone, though the behavior change wasn’t dramatic.

“I don’t think it’s fair to really expect people to understand how traffic signals operate. We don’t expect [motor] vehicles to know where they’re supposed to wait.”
— Stefan Bussey, Portland State University

“I don’t think it’s fair to really expect people to understand how traffic signals operate,” Bussey said in a seminar last week presenting his results. “We don’t expect vehicles to know where they’re supposed to wait to get a green, so ideally we won’t expect cyclists to know where to wait to get a green.”

City of Portland Signals Division Manager Peter Koonce, who assisted with the study, agreed.

“Is it good for all users? Does everybody feel comfortable?” Koonce asked last week. “The answer to that probably is no.”

Koonce said his team has experimented with microwave, thermal and video signal detectors as well as the more common metal detectors. Back in June we reported on PBOT’s new blue indicator lights.

“It’s easy to detect a car,” Koonce said. “Bikes are different.”

In the short term, Bussey said, his best solution is for bikers to “share the knowledge” with each other.

That’s what he does.

“About once a week, I tap somebody on the shoulder at an intersection and say hey, wait over there — you’re never going to get your green,” he said. “People don’t always like it, but I feel like hopefully I’m doing them a favor in the long run.”

— Want to know more about how signal sensors work and how to trigger them? Read PBOT’s how-to via this PDF and re-read our Bike Science: Making sense out of traffic signal sensors story from 2010.

Corrections 11/14: Bussey is pursuing his second bachelor’s degree. An earlier version of this post incorrectly described him as a grad student. Also, the city’s experimental blue lights operate electronically, not by radio.

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  • BIKELEPTIC November 13, 2013 at 10:10 am

    only half? I would guess higher. I feel like every freaking time I am at a light I am yelling across the road for someone to trigger that side or asking someone next to me or in front of me to line up one the bike. Sometimes I am on an unstandard bike like a freak bike or a carbon fiber which I can’t trigger the light with.

    Majority of the time they can’t hear me because they have earbuds in and we sit there for three light cycles like idiots; them wondering why the light isnt changing. Finally a driver will show up or another informed commuter.

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    • Joseph E November 13, 2013 at 12:36 pm

      Your carbon fiber bike should still trigger the light, unless you also have carbon fiber rims. In that case, yeah, you are out of luck.
      In fact, an aluminum bike frame with carbon fiber rims might not trigger the light either.

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      • timo November 13, 2013 at 3:04 pm

        My understanding is the metal in the bottom bracket should do the trick, if properly lined up. Or are they making carbon fiber bottom brackets now too?

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        • spare_wheel November 13, 2013 at 4:43 pm

          i can reliably trigger loop detectors with my aluminum wheels but not with my carbon wheels or with the bottom bracket area on my plastic bikes.

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          • gutterbunnybikes November 13, 2013 at 10:25 pm

            All hail vintage steel….I probably set them off from a block away.

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  • scotth November 13, 2013 at 10:34 am

    It’s not just bike riders, it’s easily the same percentage of cars as well, I’ve witnessed. If it’s estimated that the average american spends 900 hours a year in their car ( that’s 10% of the hours in a year ), I think we SHOULD expect our neighbors to have the due diligence to understand traffic control devices. Obviously some widespread awareness is needed.

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  • TOM November 13, 2013 at 10:36 am

    At the diagonal intersection crossing @ Springwater & Johnson Creek Blvd: the green painted bike boxes over the light signal sensors are faded and ratty and many riders new to that crossing seem to miss them and wait and wait , eventually giving up and doing the old double light crossing.

    yes, I know there are signs, I pointed them out to a teacher next to me who was embarrassed that she didn’t read them or see the green box. The painted boxes look like they’ll be completely gone by next year.

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  • Joe November 13, 2013 at 10:40 am

    A group interviewed me at the one bike light off of the steel bridge asking do you think we need more bike light triggers… forsure 🙂

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  • Granpa November 13, 2013 at 10:46 am

    I have an aluminum frame bike and it frequently does not trigger the signal. I imagine that carbon bikes suffer similarly. Sure there is ferrous metal in the bottom bracket, but it may not be enough for the loop to detect.

    (sarc) Half of bike riders don’t know how to trigger the green lights, and the other half don’t know how to obey red lights (sarc off)

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    • Dimitrios November 13, 2013 at 11:00 am

      This is a common misunderstanding. The detection loops are not magnet-based. Check out the “Bike Science” link provided at the bottom of the article. I have steel, aluminum, and carbon fiber bikes all of them can trigger a light. They all have aluminum wheels, which is what’s being detected.

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  • Frank November 13, 2013 at 11:14 am

    I would also note that 90% of people who are told nicely that they are not using the trigger and are in fact blocking it respond by acting like you are a know-it-all jackass for pointing it out, no matter how polite you are. And then they often don’t use it anyway. As a result, I have ceased my public education efforts and just sit there waiting and waiting and waiting. I’d rather be slowed down than deal with attitude.

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    • John Lascurettes November 13, 2013 at 1:01 pm

      Note the mark is usually denoting the sweet spot on the right side of a ring loop. You can just as easily align yourself with the left side of the ring loop (when it’s visible) and it will have the same effect as aligning where the paint mark is.

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    • was carless November 13, 2013 at 6:26 pm

      I just go around and plop my bike on the induction current, idiots be damned!

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  • MaxD November 13, 2013 at 11:16 am

    Those things are terrible! They are often so work you can’t see them. They force you into a strange position in the lane. They barely work. The lights they give are super short.

    As an example, riding north on Interstate Ave, one can turn left on Overlook to get off the miserable, substandard bike facilities on that street. However, the bike “trigger” is super worn- basically illegible. I have been using this long enough that I can find it: it is waaaaaaay over to the left, placing the cyclist inches from the MAX. It is also so far over that cars often do not see a cyclist at first. So when one finally gets in position, this thing does not really give bikes any sort of priority- you wait and wait, hoping the next distracted driver won’t come up behind you and plow you into the MAX. When it eventually turns green, it is for the blink of an eye! One a bike, you have to swing wide a little to cross 2 sets of tracks somewhat perpendicular, but even with hustling, the light for the cross traffic CONSISTENTLY turns green while I am still in the lane. I even watch the lights and take off a few seconds prior to getting the green.

    These little marking are super weak, and the system they trigger sucks even worse. Get it together, Portland!

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    • wilf November 13, 2013 at 12:07 pm

      I use that one also. I think it is broken, because it never changes when I am the only vehicle there.

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      • Ted Buehler November 13, 2013 at 2:27 pm

        Send in your observations and complaints to safe@portlandoregon.gov and they’ll get on it. I’ve done this for a few intersections around town, and they’ve been fixed in a month or two. Left turn off MLK to Tillamook, and southbound Vancouver at Rosa Parks come to mind. Thanks PBOT!

        Matt Picio made request for the Rosa Parks/I-5 traffic signals a couple years ago, and Peter Koonce got them changed pretty quickly, and remarked to AROW “Transport Your Activism” ride attendees that he really likes getting clear requests for traffic signal/bicycle issues, and his department usually gets on them pretty quick. (I thought there was a BikePortland story on the signals, but can’t find it. 2010 or 2011?)

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        • MaxD November 13, 2013 at 4:24 pm

          I love your relentless optimism, Ted, but I have not shared your good luck. I have requested that the giant seams across the Interstate bike lanes get ground flush, I have contacted Peter about the signal timing for bikes at SE Taylor/MLK, and NE 6th and Couch. I have called in numerous request for traffic patrols to monitor speeding. The response can be summed up “shut up and get a car”. After years of lobbying for basic safety fixes, I am burnt out.

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        • gumby November 14, 2013 at 9:31 am

          It would be easier to tell them which light sensors actually do work for bikes. I love the little blue light on the bike light at the east side of the steel bridge. It turns on when your bike is detected. You know for sure if you’re in the right spot. I bet most people don’t know what it is though.

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        • wilf November 14, 2013 at 10:15 am

          Just wrote an email. Thanks.

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    • Sean November 13, 2013 at 2:28 pm

      I agree–the lights triggered are way too short on the markings I regularly encounter. A car sitting at a light triggers a green that is long enough for other cars not currently queued up to make it through. A bike sitting alone on a sensor triggers a light that is only long enough for him/her to get thru. No bike a 1/2 block or farther away can make it thru. Often, the pedestrian signal seems like a safer bet.

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    • pdx2wheeler November 13, 2013 at 2:36 pm

      I use that left turn signal everyday. It works just fine, however, its the last travel lane to get the green light at that intersection during the light cycle. So sometimes you feel neglected, but just use the extra rest time to catch your breath after climbing the big hill between Widmer and Kaiser. MAX is very close, granted, but waiting for the green will solve any safety concerns. I fully agree the light is a bit too short, I’m often crossing through a yellow/red when following only one car. The only real safety concern I’ve had is turning left in front of oncoming bikes traveling south on Interstate, and they’re blowing through the light…

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    • J Ram November 14, 2013 at 8:15 am

      I think most of the signals turning left off of interstate are too quick. If i’m the only vehicle that triggers the left, it almost always is turning yellow before i’m across the max tracks. I think the only exception is at Alberta, which usually gives you lots of time.

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  • GreatDane8 November 13, 2013 at 11:19 am

    I am in the group that does know how to trigger the lights properly. There are three on my commute home and others that I encounter here and there. Unfortunately, I’ve found that many of them simply don’t trigger unless a car comes up behind me – particularly in left turn lanes. If I’ve waited a full cycle without getting a light, it’s the one situation I will run a red.

    Are there any tricks, besides having your wheels in the right place?

    Who do we contact if there is a signal that doesn’t trigger on a regular basis?

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    • KYouell November 13, 2013 at 1:47 pm

      I send a tweet to @pkoonce (Peter Koonce, mentioned in the article) when I find a problem. Occasionally he’s told me that I’m wrong and everything there is working but I’m not being patient enough, but usually he’s right on it and the situation is improved greatly.

      The latest example was a 4-day response time between telling him that when crossing SE Stark southbound on SE 28th I can only make it through the light if I’m first in line at the red. In only 4 days he tweeted back at me that the signal was longer. Now I can be behind 3 cars and still make it through the green.

      Another fix is the sensor and blue light signaling you’ve triggered it when going southbound on SE 16th across SE Hawthorne. A couple of Bakfiets Babes tweeted at him that it was impossible for us to use the pedestrian button there due to the size of our bikes and voila! I cannot express how happy I am to have someone like him to deal with. Thanks, Peter!

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      • BIKELEPTIC November 14, 2013 at 1:16 am

        maybe I’ll let him know I can’t reach the pedestrian button w/o dismounting due to my tall bike so they can raise the height of the buttons.

        But a couple years ago I got the sensor fixed on the North bound 12th St Bridge heading towards the Lloyd district from SE. I would leave work at midnight and hit the red light and the light would go GREEN-YELLOW-RED. Just like that. Like five seconds. I would barely make it into the intersection before it was red again. Several times I almost got into altercations with semi truck drivers due to this issue. PKoonce made short work of it and I swear it was fixed within 48 hrs.

        Sure Peter isn’t the Safe Roads Genie; but well documented encounters of the issue. Even video or photos help. Hell, there’s even a smart phone app now! PDX Reporter! You can use it to report graffiti, illegal parking/abandoned vehicle, plugged drain, potholes, street lighting, sidewalk violations, park maintenance, etc.

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    • JJJJ November 13, 2013 at 1:49 pm

      Best trick: Move your bike back and forth over the induction loop

      Best remedy: Email/call city and tell them its not sensitive enough

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  • Mike November 13, 2013 at 11:21 am

    It’s the wheel, not the bike. You need to put your wheel directly on the circle. In 15+ years of commuting in the city, I’ve always been able to get the light to change.

    I have wondered for years why PBOT and/or BTA hasn’t put up some educational billboards around town showing people how the sensors actually work. Even a little stencil “Place Front Wheel Here” instead of those bike outlines would make a huge difference.

    People, both drivers and cyclist alike, complain about cyclists that run red lights. Granted that some of them are deliberate but there are plenty of them who wait at a light for 2 or 3 cycles without it tripping and then just give up and go. Maybe a little educational outreach would cut the number down some.

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    • Jane November 13, 2013 at 11:35 am

      It seems like most of the complaining about people on bikes running red lights is due to the complainer being a moron, as opposed to actually being inconvenienced or harmed by the light runner.

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      • gutterbunnybikes November 13, 2013 at 10:31 pm

        after all you are legally allowed to run a red if it “appears” to be broken….. (hint hint)…..

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    • Erinne November 13, 2013 at 12:18 pm

      There’s a tiny sign on NE Morris eastbound at MLK that says something like “to trigger light wait on [bike signal].” Useful info–but SO tiny! Those signs probably exist elsewhere, too. They need to make them BIGGER and add hundreds more. But we really need to help people understand, too, that there doesn’t have to be anything painted on the road for it to work–if you see a circle, put your wheels on the edge!

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    • spare_wheel November 13, 2013 at 12:35 pm

      my “A” commuter wheels do not trigger loop detectors. if i lean and move the chainrings or rotors and hubs over the detector it typically fires. since these antics are embarrassing i typically just run the light.

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      • Alex Reed November 13, 2013 at 12:56 pm

        Running the light is MUCH more embarrassing IMHO.

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        • Alex Reed November 13, 2013 at 12:57 pm

          Clarification: Unless you’ve already waited through a full signal, in which case I believe running the light (safely) is legally covered as well as more likely to be understood by passersby.

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        • spare_wheel November 13, 2013 at 1:57 pm

          so you want me to dismount, lean my bike over, and drag it across the loop detector to assuage your embarrassment?


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          • Alex Reed November 13, 2013 at 2:25 pm

            Embarrassment is a social emotion, generally felt when one person thinks he is being judged negatively by other(s). I was just letting you know that other people are judging you negatively when you run red lights (myself included, but only relatively mildly – I know that most people who don’t ride bikes HATE this behavior with a passion). So maybe knowing that will trigger more embarrassment the next time you run a red light, and you might decide it’s less embarrassment than results from leaning your bike down (which is not embarrassing in my opinion – who judges you for leaning your bike over? They might be curious but that’s about it….)

            If not, oh well. You’ll continue being a small impediment to the cause of trying to have biking be more socially accepted in Portland, and that’s OK, if suboptimal in my opinion.

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          • Alex Reed November 13, 2013 at 2:28 pm

            To clarify, this small aspect of your behavior will continue being a small impediment to the cause of having biking be mainstream in Portland. Whatever else you do with your time (such as biking, or advocating for bike infrastructure!) may well be more of a help to this cause than your red-light running is a hindrance. And you may not care about the fate of this cause, in which case what I’m saying shouldn’t really matter to you!

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            • spare_wheel November 13, 2013 at 3:28 pm

              i reject the idea that slavishly following auto-centric traffic statutes help promote cycling. in fact, i believe that following these statutes often make cycling less convenient and safe.

              “I know that most people who don’t ride bikes HATE this behavior with a passion”

              you know this how? perhaps you are simply transferring your own emotional response onto the public at large. i am an enthusiastic proponent of the idaho stop and i try to practice what i preach.

              “You’ll continue being a small impediment to the cause of trying to have biking be more socially accepted in Portland, and that’s OK, if suboptimal in my opinion.”

              and your evidence for this is…(oregonian comments do not count).

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              • Alex Reed November 13, 2013 at 3:58 pm

                Evidence is anecdotal evidence from a large portion of people I know who don’t bike! When they see my bike or otherwise start a conversation about biking I hear the “But do you follow the laws? Do you run red lights? I hate the people who do that!” thing pretty frequently.

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              • Dimitrios November 13, 2013 at 4:20 pm

                I have no doubt this is true. What makes it irrelevant is that lawbreaking is not the domain of cyclists. It’s the behavior of all modes of transportation. People just break different laws based on the mode they’re engaging in. That’s why it is insignificant. It’s a convenient excuse because you can backup your dislike of something seemingly with logic.

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              • Alex Reed November 13, 2013 at 4:26 pm

                That’s certainly true. Not saying spare_wheel is an unusually lawbreaking person or anything. Just saying she or he is having a negative impact on perceptions of bicyclists by the Portland public at large.

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              • Alex Reed November 13, 2013 at 4:28 pm

                Probably would never happen, but in my opinion it would help the Cause if people would obey laws more while on bikes. I agree that this would mean obeying laws more often while riding bikes than while walking or driving. Double standards suck – but sometimes to get ahead you need to just go ahead and be better than even the higher standard.

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              • Dimitrios November 13, 2013 at 4:33 pm

                It’s just the nature of doing something in the minority. I understand it and resent it. I go back and forth in my head on the real effect of strictly following the rules will have. My gut says this is just a game of whackamole. Knock down one excuse and more will follow. Knock em all down and eventually people just say “I don’t like you”.

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              • pdx2wheeler November 13, 2013 at 4:50 pm

                spare_wheel, IMHO, cutting corners while cycling in an urban environment will eventually come back to bite you. I truly hope that the time you save cutting-corners on your precious bicycle doesn’t someday have to be repaid by you sitting in a hospital bed, or a courtroom. Ride safe Sir!

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              • spare_wheel November 13, 2013 at 5:43 pm

                i’m no fan of cutting corners, pdx2wheeler. at corners i typically filter around the obstruction on the left (or wait in the lane).

                and you ride safe too, sir!

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  • J_R November 13, 2013 at 11:22 am

    More than half of motorists don’t know they are required by law to stop behind the stop bar or the marked or unmarked sidewalk. It’s not surprising that bicyclists are equally unaware of what markings mean.

    Most times when people complain that their carbon/aluminum or whatever bikes are not being detected, it’s actually a matter of 1) not being in the right place or 2) not recognizing all the competing phases through which the signal must go through to get to their phase.

    I have also encountered some loops that didn’t seem to detect my bike and received very prompt attention from the Portland signal crew when I called.

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    • John Lascurettes November 13, 2013 at 12:07 pm

      The loops, when attuned right, will pick up any metal – not just ferrous metals.

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      • spare_wheel November 13, 2013 at 10:01 pm

        many areas calibrate them to a standard mtb rim. obviously this could result in negative signals for many bikes.

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  • Lenny Anderson
    Lenny Anderson November 13, 2013 at 11:32 am

    Study sure confirms my experience!

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  • Scott November 13, 2013 at 11:35 am

    Wait….according to the other study, don’t we all just run those?

    Now I’m confused.

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  • Skid November 13, 2013 at 11:39 am

    And 99% of motorists have no idea what makes a light turn green either. Especially the overly cautious ones who won’t pull forward far enough to be over the sensors because I am already waiting at the red light.

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  • Peejay November 13, 2013 at 11:41 am

    I always use the position marker, and still end up not triggering the light. I’m fine with the idea of croudsourcing malfunctioning sensors, except when the vast majority don’t work.

    This is why I don’t feel bad at all going through the red.

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  • John Lascurettes November 13, 2013 at 12:06 pm

    I always use either the position marker, or if there is none, I’ll still align my bike over the detector loop seams in the roadway if they’re visible.

    Sometimes that means pulling up alongside a biker that seems unaware and they might think I’m shoaling. I usually explain that the light won’t change until they trip the sensor and this is the way to do it.

    Sometimes when I’ve pointed it out to another rider I get an incredulous look from them like what I’m saying is an untruth. It’s weird.

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    • davemess November 13, 2013 at 1:52 pm

      I’m just shocked that more people aren’t curious what they are. They are quite obvious. They’re a bike directly on the signal coil!?!?!?!
      All the ones on my various commute routes work just fine (Ladds/Division, 52nd/Woodstock, etc.).

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    • spare_wheel November 13, 2013 at 2:12 pm

      if you are pulling up alongside a cyclist you not shoaling.


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      • Bald One November 13, 2013 at 4:18 pm

        I prefer the more local term “green flagging” to shoaling, but that article is hilarious. Not all Portland stops have green flags, so maybe we can call it inductive chivalry.

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    • mh November 14, 2013 at 3:28 pm

      I rarely get grief when I advise people what actually works (or should work). Most of the time during rush hour, though, there’s enough metal on the road that I could just shut up. But I hope they’ll remember for the midnight rides home.

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  • Adam November 13, 2013 at 12:34 pm

    I am surprised it is as low as half. From my observations, about eight out of ten cyclists don’t know about bikes and loop detectors at all.

    The biggest problem is the red light running this level of ignorance inadvertently causes. Watch any intersection. A bicyclist pulls up. Doesn’t line their bike on up the loop detector (because, uh, why would they? Nobody has told them how or why ever in their lives). They sit though a light change, and nothing happens. Another light change comes and goes. Still no green light for them. Finally, out of frustration, they run the red.

    I see this time and time again.

    We need little spraypainted road markings with an arrow that say “line bike up here to trigger light”.

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    • davemess November 13, 2013 at 1:53 pm

      Again, there is a bike stencil directly over a signal coil in the street. Maybe I am giving the general public too much credit, but these seem pretty intuitive to me.

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      • Alex Reed November 13, 2013 at 3:02 pm

        You’re giving the general public too much credit. I have taught dozens of cyclists about this over the years.

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      • Adam November 13, 2013 at 5:36 pm

        I’m sorry Dave, but unless you are a traffic engineer, most of the bike infrastructure here in Portland is not particularly intuitive. This study pretty much confirms that, I’d say.

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        • davemess November 14, 2013 at 11:28 am

          So you’re saying that most people don’t know what the coils on the street are for? I didn’t think it took a degree to figure that out, but again maybe I have too much faith in humanity.

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  • GlowBoy November 13, 2013 at 12:48 pm

    Even when there isn’t a bike stencil, you can usually see the cuts in the pavement where they installed the inductive loop. Just place your front wheel just a few inches inside the loop and you’ll usually trigger the light.

    As long as I do that right I find very few signals that fail to detect me, and almost never have a problem within the city limits. The only places I have problems are some westside intersections with optical detectors rather than loop detectors: Millikan at Murray, Laurelwood at Scholls Ferry, and Main at Denney.

    And as said by others above the pavement loops are indeed inductive, not magnetic, so they will be triggered by ANY conductive material – including aluminum and titanium. Except in the rare case of a carbon fiber bike with carbon fiber wheels, a properly adjusted pavement detector should sense your bike.

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    • John Lascurettes November 13, 2013 at 1:06 pm

      Also note that those detector loops are often visible (box or diamond shape) in bike lanes at intersections, so they’ll trip the light too (and often are programmed for better responsiveness).

      There is one at the bottom of westbound Broadway just before hitting the bridge though that is positioned so far left, it’s mostly out of the bike lane and in the auto lane. Lame. I’ll still position my bike over it best I can if there’s no cars.

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      • John Lascurettes November 13, 2013 at 1:12 pm

        BTW, the PDF linked to in the article covers how to find the sweet spot of the different shaped detectors. It’s great information. Use it!

        The fact that the sweet spots are wildly different doesn’t go to helping the issue at all for the ignorant. I dipole detector has a wildly different sweet spot than a quadruple detector. And square is different than round.

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  • El Biciclero November 13, 2013 at 1:04 pm

    My research always seems to show the converse of the results Mr. Bussey has come up with. What I find is that 55% of traffic signals don’t know what a “bike” is.

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  • jocko November 13, 2013 at 1:04 pm

    I have also bee told that even the metal in your bottom bracket will trigger the signals for all of you with plastic bikes and plastic rims.

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    • spare_wheel November 13, 2013 at 2:02 pm

      this is true. but to do this i have to clip out, dismount, lean my bike flat across the ground, and drag it across the loop. for me the risk of scratching “my precioiusssssss” greatly always outweighs any lingering desire i have to be a “bike ambassador”.

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      • Ted Buehler November 13, 2013 at 2:19 pm

        Leaning your bike flat is an approved technique in the Oregon Bicyclist Manual. See Page 13, 2nd figure.

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        • Alan 1.0 November 14, 2013 at 9:23 am

          At a busy intersection with impatient drivers breathing down my neck they expect me to dismount and drop my bike to the ground, taking my attention off the traffic around me and lowering my profile in drivers’ vision? That author’s experience of road use must be very different than my own.

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          • John Lascurettes November 14, 2013 at 9:41 am

            You’re not also lying down are you? Tall bikes being the exception, riders are always taller than the bike.

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            • Alan 1.0 November 14, 2013 at 10:02 am

              I ride DFs. Look at the picture Ted mentioned and then try it yourself. Unlike the PDOT cartoon, my head drops at least two feet below where it’s normally located, more if my bike is loaded and I need to brace my arm on my knee. My attention is drawn away from surrounding traffic. Maybe that maneuver will trigger a stubborn light in some cases but for my experience it’s not worth the risk. Me, if there’s so little traffic that it’s not a concern, I’ll just legally go through the light. If there’s traffic, I’ll roll forward to let the car behind me trip it.

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              • Alan 1.0 November 14, 2013 at 10:04 am


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  • Richard November 13, 2013 at 1:06 pm

    On well used bike routes, bikes or peds will trigger a green every cycle anyway so might as well use timed signals for bikes and peds. This is what Vancouver BC is starting to do and it works great.

    The other option is cyclist operated buttons which are fine on roads with little car traffic.

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  • tony tapay
    tony tapay November 13, 2013 at 1:17 pm

    One of the first thing that I learned in design school is that if a substantial number of users fail to use your product properly, it’s not the users’ fault, it’s the fault of the product design. If the VAST majority of users cannot intuitively figure these things out, then the design has failed. Period. You don’t get to blame the users because your job as a designer is to make your product understood.

    I know how to use these and they mostly work fine for me, but I’m always seeing people get it wrong at SE 42nd/43rd & SE Powell. (It’s a terrible intersection and the sensors will often reset if you shift even just a little bit. It should be on a timer.)

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    • John Lascurettes November 13, 2013 at 1:26 pm

      Part of the problem is loops are designed in general to pick up 4-wheeled or larger vehicles best. Add to that that the sweet spot of different detection loops are wildly different, is it any wonder?

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    • Dan Morrison November 13, 2013 at 1:38 pm

      Vast majority is half? Some design school…

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      • tony tapay
        tony tapay November 13, 2013 at 2:31 pm

        At no point in the first paragraph was I referring directly to the topic at hand. I was discussing design failure at large.

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    • Justin November 13, 2013 at 2:25 pm

      That’s an unfortunate crossing in general, a bike route crossing a major highway at an offset intersection. I keep wishing that they could use the empty property on the northwest side of the intersection to square off the intersection so it isn’t such a hassle.

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  • Ted Buehler November 13, 2013 at 1:36 pm

    2 ways to do some easy public education to counter this:

    1) install some “bikes wait here” stencils around town. On 1 in 20 signals maybe. Folks would catch on pretty quick. As I recall, an earlier version of the marker had that text.

    2) get some local friendly police officers or volunteers to hand out copies of the “Oregon Bicycle Manual” to riders that appear to be novices. It’s a great read, its very well presented in terms of instructing Oregonians how to operate a bicycle on our streets.

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    • Ted Buehler November 13, 2013 at 1:40 pm

      For longer term, and broader changes, perhaps the MUTCD should change the image so it has both a bicycle and a traffic signal. Since 34% of respondents thought it just meant “bike route” it might warrant a change.

      For instance, the stencil could also have a bicyclist with their foot down, indicating its a place to wait.

      Or, a 2-part stencil, with
      [bike & bicyclist with foot down]
      [monochrome traffic light with bottom light illuminated]

      Either one would convey the information much more clearly than the existing symbol.

      Nice research — thanks for going to the effort to conduct it, and sharing it with the masses.

      Ted Buehler

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    • Ted Buehler November 13, 2013 at 1:45 pm

      And here’s the MUTCD official sign to inform bicyclists that that little symbol is where you wait. Maybe Portland just needs to put up another 100 of these around town.
      Sign R10-22

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      • Ted Buehler November 13, 2013 at 2:00 pm

        So, folks, here’s something we can do.

        My understanding is that PBOT doesn’t have the $ or mandate to go around and make changes like installing optional signs that complement these pavement markings. If, for instance, a PBOT employee was to get the notion that bicyclists would be better served by Portland streets if there were a bunch of R10-22 signs installed around town, the bean counters would probably say “sorry, no can do. Would you like to write a grant for $20,000 for 100 signs? We can get it by 2016, and get them up in 2017”

        But, the city will respond to citizen facility improvement requests on a case by case basis.

        So, if you’re riding around, like at Seven Corners, and you see that cyclists are not using the Termoplast pavement marking to trigger the green signal, look around and see if there’s one of those nifty R10-22 signs at the intersection. If not, send an email to safe@portlandoregon.gov and say
        “I observed a bicyclist going south on X St at the Y Ave traffic signal. They weren’t aware that they should wait on the Bicycle Detector Pavement Marking (MUTCD Figure 9C-7) to trigger the signal. Can you install informational sign R10-22 at this corner to instruct bicyclists as to where to wait to trigger the signal?”

        Then, if 20 of us request about 50 of these around town, they signs come out of the maintenance budget, and they will get installed within a month or two of the request.

        Comments, corrections, additions?

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        • Ted Buehler November 13, 2013 at 2:02 pm

          This is based on PBOT’s instructions to roadway users, found at

          “Your experience helps guide real solutions to traffic safety problems, and the Portland Bureau of Transportation wants to hear from you. When you have a concern, please call the Transportation Safety and Neighborhood Livability Line (823-SAFE). You may also email safe@portlandoregon.gov. Your call will be returned within approximately 3 days or your e-mail within 10 days.”

          “The Safety and Livability Line helps the Transportation Bureau respond to the following transportation safety issues:”
          Traffic Safety Issue _ _ Examples of Service Requests

          Intersection Safety _ _ Pavement Markings / Signals / STOP Signs
          Bicycle Safety _ _ Bike Lanes / Parking / Signals / Visibility

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      • Erinne November 14, 2013 at 10:35 am

        One problem with R10-22, which I’ve seen in only one place, is that the one I saw is REALLY TINY. I seriously commuted through that intersection for *over a year* before I finally noticed it. :-/ Do they or can they come in larger sizes, I wonder?

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  • Matt November 13, 2013 at 1:41 pm

    As a Floridian, I’m going to confirm what was posted above about us Floridians not knowing how to trigger signals with the above mentioned road marking. The reason for that is because no where in the state has FDOT placed that road marking on any state roads, nor has any county or city DOT done so. Hell, we are just starting to see Sharrows put into place within the last year.

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  • JJJJ November 13, 2013 at 1:50 pm

    I find this odd. When I commuted to work by bike, I very quickly learned how to trigger every light on my way. I also learned which one didnt work, and had to be run.

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  • Alex Reed November 13, 2013 at 2:05 pm

    I have to admit I hate these loops, and the “beg buttons” for pedestrians too. What was so bad about timed signals again? I’ve heard the “efficiency” argument, but the change from timed signals to detection seems to have increased “efficiency” for motor vehicle transport and decreased it for non-motor-vehicle modes (on average).

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    • Dimitrios November 13, 2013 at 2:38 pm

      The catch-22 of “efficiency”. There is already such a large investment in inefficient transportation that the status quo is to make all benefits of efficiency go towards the least efficient. That where the biggest gains are to be had.

      I love cycling but it’s not lost on me the roundabout ways I tend to ride to avoid main arteries and all of the consequences of that decision that follow. If main roads were accommodating to all modes this light triggering becomes much less of an issue. No more 50 turns and stop signs/lights to get to the same destination by car.

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      • dr2chase November 14, 2013 at 11:35 am

        YES, exactly. Had someone point out to me that the largest benefits of hybrid auto technology come from adding it to SUVs — because the more energy is wasted, the more there is to save.

        True, but aaaaaaarrrrrrrg.

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    • Oliver November 13, 2013 at 4:55 pm

      idk. I find lights on a timer quite annoying when I’m rolling fast along a deserted street and get stopped for an entire cycle with for nowt but the crossing of the proverbial lone tumbleweed. In the grand scheme of things this is worse than the occasional snafu with induction loops.

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      • Alex Reed November 13, 2013 at 7:44 pm

        Generally the “bigger” street gets a constant green at night at signalized intersections that are loop/button activated. So, it sounds like you ride at least a good bit on minor/major arterials (because you encounter signalized intersections with smaller streets). I think the majority (though certainly not the vast majority) of riding in Portland happens on neighborhood greenways, which are not minor/major arterials and tend to lose priority to when intersections are made loop/button activated. Possibly you benefit when intersections are made loop/button activated but the majority of Portland cyclists lose?

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    • Chris I November 14, 2013 at 8:01 am

      DIY timed signals: glue a thin sheet of metal over the sensor loops at your favorite intersection.

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  • Josh G November 13, 2013 at 2:57 pm

    So what does your average carbon rimmed urbanite do… run the light or walk over the the ped. signal? I’m not talking legally.
    You can always hear carbon rims coming behind you.

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    • John Lascurettes November 13, 2013 at 3:16 pm

      “So what does your average carbon rimmed urbanite do… ”

      Mostly get laughed at.

      Seriously, there’s not an ounce of metal on the bike? It doesn’t take much and it doesn’t have to be ferrous.

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      • spare_wheel November 15, 2013 at 8:02 am

        actually if you go back and read the the bike science post (some citations in the comments) it’s clear that it does take a particular amount of conducting material at a particular height.

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    • Paul in the 'couve November 13, 2013 at 3:23 pm

      safely – run the red – safely

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    • basketloverd November 14, 2013 at 9:21 am

      Pedal spindles are still metal, for now. Lean the bike over a bit.

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  • Richard Kilshaw November 13, 2013 at 3:50 pm

    How about placing a loop way earlier in the bike lane before the junction? Could a moving bicycle trigger the signal as easily as a stationary one? If so, the signal change could be timed for a bike rolling the lane at say a calm 10 mph and delay accordingly. People would adjust their riding speed for a comfortable roll through and everyone wins.

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    • John Lascurettes November 13, 2013 at 7:38 pm

      The westbound approach to the broadway bridge has some mid-block loops in the lane – not that I think they do anything. I seem to catch more reds than I catch greens on the morning commute.

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  • Puddlecyle...is your destiny November 13, 2013 at 10:17 pm

    Like many good bike things (Shift2Bikes, the BTA, BikePortland, free coffee at Burger King if you’re wearing a chamois), the only reason I know about traffic light triggers is because someone told me about it – let’s all keep telling each other about things.

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  • Chris I November 14, 2013 at 8:00 am

    I noticed that PBOT has started adding rectangular sensor loops in the bike lanes on a few roads. 122nd in east Portland was just repaved this year, and now the bike lane has a rectangular sensor loop about 10ft back from the intersection. I make sure to roll over it if the light is red, and it always works; I usually do not have to stop.

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    • Scott Barker November 14, 2013 at 9:13 am

      There are various types of inductive bike loops (quadrapoles) that will detect a bike, regardless of location above the loop. I’m guessing that you are looking down at a 3’x6′ bike loop (saw-cut install). I work for a company that builds this spec, but they are preformed, and installed before paving(see link below). Because of the center leg, the loop is ‘hot’ not just on the sides, but even more so in the middle.


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  • Tiago DeJerk November 14, 2013 at 8:19 am

    In my experience, these sensors are so unreliable I just don’t count on them. It’s humiliating to be just waiting for a car to show up and trigger the light for me. Having to tell PDOT that there’s a problem and nothing happen is an infuriating double-standard: having a traffic light that never turned green for a car unless a bigger car came by or the driver had to get off the car would be unacceptable.

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  • TOM November 14, 2013 at 9:59 am

    >>Want to know more about how signal sensors work and how to trigger them? Read PBOT’s how-to via this PDF

    bad link

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  • Eric in Seattle November 14, 2013 at 10:03 am

    At least Portland is using the standard bike stencil. Up here in Seattle they have this somewhat mysterious “T” shaped mark. It’s almost like they are trying to hide the fact that a bike can trigger the sensor.

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  • Peter Koonce November 14, 2013 at 12:23 pm

    Thanks for the comments. I am continually impressed with the feedback that we get from BikePortland.org readers. It is quite a service that Jonathan and Michael provide that is inline with one of the 4Es of Transportation: Education. I will try to cover many of the comments in one post.

    PBOT has over 1,000 signals that we maintain. That’s a lot of traffic signal heads, signs, and markings. The staff of PBOT do our best to keep the streets working well for everyone in the City and the region. This post and the study was intended to document the state of the practice and set a course for how we as a City and nationally improve traffic signals for bicycle travel. Here’s some thoughts from a signal engineer:

    “Problems” with Existing Detection Systems may just be the Timing

    There are times that the traffic signals will be operating in a way that seems counterinutive. It may be because we haven’t changed the signal timing for several years. Stefan Bussey actually served the City of Portland as an intern and he updated timing at many of our bicycle/pedestrian signals during his short time at PBOT. You may find that you experience less delays on neighborhood greenways if your walking or riding your bike thanks to the work of our signal timing engineers and Stefan. More information on that work can be found here: http://otrec.us/files/Bussey_Half%20Signals%20Report%20FINAL.pdf.

    Engineers prepare for traffic on the main street because that’s where the majority of people are. We’re making the best of the infrastructure that was built in the last thirty years. As some of the commenters suggest, there may be times when you have to be patient with us. In some cases, if you let PBOT know by calling 503-823-CYCL, we may be able to improve things. In any case, call us and provide detailed information including the time of day and location that you are experiencing traffic signal delay and we’ll evaluate whether we can do better. National readers (from other states): your response may vary. Portland transportation policies are to encourage multimodal travel.

    Improving Detection Design

    One of the challenges that we face is that there isn’t a one size fits all design. Traffic design standards have changed. What used to be commonplace wasn’t always effective for bicycle traffic, so while we have changed those standards, we continue to deal with 20, or 40-year old technology. While we are designing the transportation system for vehicles and people, some of our infrastructure isn’t adequate. Detectors don’t last long in pavement that isn’t structurally sound. We’re testing video detection to find ways to make the systems work more effectively.

    Pedestrian push buttons are helpful for locations where people on bicycles intersect with the pedestrian movements. One of the complaints on NE Multnomah is that the signal timing doesn’t seem to favor people on bikes in both directions. The constraint on that corridor is not that we are prioritizing vehicle traffic, but rather that we’re timing the signals to cross pedestrians that may or may not be crossing NE Multnomah.

    This research is helpful in highlighting that the standard detection striping doesn’t perfectly communicate what we intend for people on bicycles to do and where to be, so clearly that’s a next step for improvement. This first step is documenting the problem, clearly Portland is better off than other communities. Striping alone might not be the best thing to use, signs (as many of you indicated) aren’t always noticeable, striping fades over time.

    What Would Make Traffic Signals Better to Interact with?

    The City of Portland is committed to make traffic signals more effective for multimodal travel. A primary goal of being involved with the National Committee of Uniform Traffic Control Devices is first and foremost to make bicycle signals part of the Manual that traffic engineers use. That is being reviewed currently. Another initiative is to include an ability to provide user feedback (the aforementioned blue light that we have tested or this example out of the Netherlands: http://koonceportland.blogspot.com/2011/07/bicycle-countdown-signal-time-to-green.html). The example is not something that is sold in the U.S. because our standards don’t call for traffic signals to provide this type of information. In any case, you’ll note that in each case the systems are interfacing with the user in ways that our infrastructure hasn’t before. There needs to be some discussions about the burden of maintenance which is something we’re evaluating as we develop these new techniques and devices.

    In closing, I want to thank our partners at Portland State University for studying this further. The work they are doing has a national impact and for that I am grateful.

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  • TOM November 14, 2013 at 3:51 pm

    Thanx for that post Peter.
    I rode out Powell today,it’s just undergone a lot of work , and noticed sensor diamonds at both se 148th and at 162nd. Didn’t get a chance to test them as I did have GREENs both times.

    They were positioned about 15/20 feet before the crosswalk, and I did wonder why they were so far back ?

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  • TOM November 14, 2013 at 3:52 pm

    oh, I should have said ..they were actually IN the bike lane, where cars would not register.

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  • Ty November 14, 2013 at 7:09 pm

    I didn’t know that’s what those markers meant either – not that it matters. Riding motorcycles for decades teaches a thing or to about these things, and my experience is that those suckers don’t always trigger green even for a much larger chunk of metal. Apply common sense if it doesn’t work…

    A suggestion I’d give to educate more cyclists – put up a sign or markings around the heavily bicycle trafficked intersections to make it obvious that is what the symbol means. That way when we see it elsewhere without the signs/markings, we will already have the association from learning about it at the busy intersection.

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  • Champs November 15, 2013 at 1:03 pm

    Echoing others it’s hard to believe the number is even close to half.

    Personally I’d kill for a loop detector on SE Ladd at Hawthorne instead of having to divert over to 12th to get on Madison.

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    • Alex Reed November 15, 2013 at 8:25 pm

      Not sure if there is a loop detector there or not, but did you know that SE Ladd only gets a signal every other cycle for SE 12th and Hawthorne?

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  • Spiffy November 16, 2013 at 8:56 am

    this is what we get when we design roads for speed first and not safety first…

    I think that all the lights in the city should be changed to timed signals of equal length per crossing… this way each direction waits the same length… it’s an easy solution to calm traffic and give people walking and biking some more speed…

    the streets would be safer and more people would get out of their cars due to the slightly increased drive times…

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  • Ben (79pm) November 17, 2013 at 10:15 pm

    I’ve been taking the left from Capital Hwy going east onto Terwilliger for 15 years. I’ve never been able to reliably trigger that sensor. It was so-so for a few years, when the loops were first installed and I could see them but now I cannot placing my bike over the symbol. (That’s with ti and steel bikes, all with aluminum rims.) And since that symbol is close to the lane of through traffic and that traffic passes me at around 45 mph, I am not willing to hang out there long. I’ve run that light many, many times.

    The left turn from westbound Vermont on to Bertha has no sensor and it is only on a blue moon when I actually trigger that light. (I have no idea where the loop is.) I’ve ridden slowly (fully lit and wearing yellow reflective clothing) across Vermont to hit the pedestrian sensor in winter when Bertha was busy and been nearly hit by a a right turning motorist who was furious I was there.

    I take that left onto Bertha coming home so I do not have to do the lane change on Beaverton Hilllsdale going west to continue on Capitol. Taking the left into Wilson High and riding through the parking lot to Vermont strikes me as far safer. (I can trigger that sensor more often then blue moons, but not much. Maybe one in 12?)

    Oregon law, I believe, considers bicycle to be vehicles with the rights and obligations of other vehicles except where specifically addressed in the statutes. I’ve had police officers tell me they could site me for running lights I can’t trigger. I’ve often thought then; how ’bout this for a revenue producing scheme for towns and cities? Disable the sensors in the auto lanes at a key intersection, then just have an officer or two spending the day writing tickets.

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  • Dan November 18, 2013 at 6:19 pm

    As far as I can tell, these have never worked for me, so I obviously stopped bothering to try. I can’t think of any change-of-signal cycling devices that work well in Portland, compared with the immediacy with which they work in Vancouver, BC. I think push buttons are best, if allowed to actually signal a change, quickly.

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