Preventing the Left Cross

The left cross is the crash type we bicyclists have most in common with motorcyclists. The techniques for preventing it are the same as those taught in motorcycle school. Of course, it’s much easier to learn in motorcycle school because there is no baggage of taboo or fear surrounding operating a motorcycle away from the curb. And our culture doesn’t build special motorcycle facilities that violate the principles of normal traffic movements. But we can overcome that.

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An invitation to get hit

Passing a queue of cars on the right is a high risk activity, in most cases. The above photo is the scene every day on Edgewater Drive at lunchtime and rush hour (at lunchtime the parking spaces are full). My first response to this situation was, “Oh good! they’re stuck and I have a clear lane!” I was disabused of that notion by the front quarter panel of a Jeep Cherokee.

Between getting hit and other constant conflicts, I learned to ride slowly (6-8mph) when passing the queued cars, and to be prepared to stop any time there was a car-length gap between 2 cars. A gap often indicates a good-Samaritan is letting another driver turn left. Even so, the blocks between Yale and Vassar are so conflict-ridden, it’s easier and safer to wait in the queue than to try to pass it. Even when traffic is moving, I usually avoid the bike lane there.

Other factors

Low light conditions are always going to be an issue for visibility and speed-assessment. For the most part, I find motorists are more cautious at night. twilight conditions present problems for the human eye, it’s a good idea to have bright lights. A blinking light at dawn and dusk will get attention, but it also sends a subliminal message “slow vehicle.” In the dark, a blinking light makes your speed and location very difficult to assess—front blinkies should not be used in full dark. We tell our students to look like a bicycle (slow) from the rear and a motorcycle (fast) from the front. It’s especially critical if you are riding fast. Ahem. It’s particularly silly to use tiny “be seen” LEDs while riding 24mph on the way to an early morning club ride. Really, that extra few grams for a good headlight will make you stronger anyway.

Light triangulation can also help motorists assess your speed in the dark. If you have one on your helmet and one on the handlebars, a motorist can better tell when you are getting close and going fast.

The left cross is not your fault, but it is in your interest to prevent it

Even left cross crashes that occur when passing stopped traffic on the right are the legal fault of the motorist. But they are completely avoidable. Moving screen left cross crashes are avoidable, too, by making yourself visible. High-speed, left cross crashes are mostly discouraged with good lane position, but a high-speed cyclist must always be on guard for this, like a motorcyclist. If you see someone preparing to make a left turn, try to get their attention, keep pedaling (without pressure on the pedals) so you don’t give them the wrong idea, and prepare for an emergency maneuver. That is why we teach emergency maneuvers!

Understanding what causes crashes is the first step to preventing them. The frightening, unpreventable acts of gross negligence are the ones we hear about because our culture is addicted to stories that make us feel horrified and helpless. But the truth is, the majority of car-v-bicycle crashes (and scary moments) are common, predictable and preventable… even when they are the motorist’s fault.

“I didn’t see you”

One of the primary factors in bicyclist left cross crashes really is a lack of visibility. Bicyclists have been taught, bullied or forced by law to operate on the margins of the road. A motorist’s focus area is on the center of the travel lane, where he expects a large, fast-moving vehicle (IOW, a threat to him) to be. Anything on the periphery (edge of the road, bike lane or sidewalk) is often not noticed. This is especially true if a motorist is shooting for a gap to turn left from a multi-lane road. I almost hit a sidewalk cyclist on Colonial once as I was making an unprotected left into a shopping center entrance. I waited and waited for there to be a big enough gap in all three lanes, then I hit the gas. I didn’t see the cyclist until I was almost across the road.

For the purpose of this post and the above animation, I’m focusing on roadway cyclists. Keep in mind that the center of the lane is the most-visible and risk-free place to be, anything father right adds risk, increasing with distance from the center. So the sidewalk is the least visible place to ride.


I’ve experienced a lot of left-cross conflicts in my years of riding. The most frightening have been when descending a hill (not in Florida). Those are the most similar to motorcycle crashes in that I’m totally visible in the center of the lane, but the motorist turns anyway. They see me, but discount my speed. This has happened to me on a flat road while hammering, too. They just don’t realize how fast we can ride. Downhills and tailwinds make all cyclists fast. I can effortlessly get close to 30mph with a strong tailwind.

Of course, I’ve also had a few that seemed less an innocent mistake than an act of complete disrespect. On Virgina, a driver turned his Mustang in front of me, then slowed to a near stop—blocking my lane—so he wouldn’t scrape his precious air dam on the gutter. It was one of those rare days I was in a hurry, and it’s slightly downhill, so I was moving fast. I was able to brake enough for the car behind him to clear, then go into the empty oncoming lane to pass him. I probably would not have had the room to do that had I not already been in the middle of the lane. I might have had enough room to do a quickstop, but I’m not sure.

A cyclist who is moving fast (for a cyclist, that’s ≥18mph) needs to ride farther out into the lane, no matter the lane width. This has nothing to do with your speed relative to overtaking traffic, it has to do with your ability to react to pavement obstructions or cars which might suddenly enter your path. With the exception of winding mountain descents, cyclists on an open road will usually be slower than motor traffic. That’s OK. It is the responsibility of overtaking traffic to yield (first come, first served) and pass safely. You have a responsibility to yourself to be visible, predictable and have room to maneuver.

The moving screen

Operating alongside the flow of traffic creates a perfect set-up for the left cross. The passing traffic screens the cyclist from left-turning motorists. If you are operating to the right of traffic (in a wide lane or bike lane) and are being passed by a line of cars, be aware of any gaps. When the last one passes you, any cars waiting to turn left will be ready to jump. This can happen at any intersection or driveway. I’ve experienced this more times than I can count on Edgewater Drive. It’s VERY common at the entrance to Publix in College Park.

The moving screen can be a problem in a narrow lane, too. If you stop on the right behind cars, you will be hidden. As the cars in front of you pull away, they’ll form a gap for a left-turning driver who cannot see you. When stopped at a traffic light, you should be positioned behind the left side of the car in front of you. Ride through the intersection on the left side of the lane so you can see, and are visible to, the driver of any car waiting to turn left. See Vantage in the Queue

35 replies
  1. danc
    danc says:

    Keri thank you!

    Posted link on Columbus blog Yaybikes, left cross on the northeast corner of Ohio State campus. Ugly video, luckily the cyclist walked away from the crash.

  2. Jayeson
    Jayeson says:

    There is another possible contributing factor – the driver may not know they are supposed to yield. The Florida driver’s knowledge of pedestrian and cycling laws is not confidence inspiring. On one occasion as I shook my head at a left-crosser they yelled back, “I had my turn signal on”.

    • Keri
      Keri says:

      LOL! I hadn’t considered that, but I think it’s true for some drivers. I’ve had a few situations where I felt like the driver might have been thinking s/he didn’t have to yield to a bicyclists.

      Anything is possible when you can get your driver license from a crackerjack box.

      • Mighk
        Mighk says:

        I’ve had overtaking drivers pass me while I’m signaling a left turn from the middle of the lane on a 2-lane street. I wonder if some younger drivers don’t understand hand signals.

        • Wayne Pein
          Wayne Pein says:

          There is always the possibility of a driver brain fart. I’ve seen left or right blinkers and the driver turned the opposite direction.

          I love your “moving screen” framing and graphics. But I wonder if a dashed line to the Left Crosser’s eye would further indicate to readers exactly what is occurring.

          • Mighk
            Mighk says:

            It occurred to me that that line from the motorist’s eyes, past the rear end of the screening vehicle, to the bicyclist, changes its angle as the screening vehicle moves through the intersection. But I didn’t want to complicate Keri’s animation task. ;^)

        • rodney
          rodney says:

          On E. Michigan St @ Fredrica Dr., I’ve had TWO a-holes do a left turn onto Fredrica while I am stopped in the LHTL, signaling and waiting for oncoming traffic to clear.

          Most drivers young or otherwise are given only enough information in the drivers “study” manual to be a danger to themselves and others.

    • Mighk
      Mighk says:


      The road that crash happened on is a very narrow, lightly traveled rural road. Hugging the edge is really irrelevant to that crash (and the story said nothing about his lane position). I doubt he could have done much to avoid the crash.

  3. Richard Masoner
    Richard Masoner says:

    My one left-cross was 30 years ago, when I was 15 years old. I was hidden behind a truck and the motorist waiting to turn in the oncoming lane shot through the gap, not anticipating my presence. It was shortly after that I read Forester as a teen.

    I still pass on the right alongside congested traffic, but like you I go slowly and watch for the motorists looking for gaps to cut through, and I (usually) stick behind the vehicle when approaching intersections.

  4. John Allen
    John Allen says:

    Keri, thanks for the second chance at a reply. Here’s what’s left when I leave out a couple of inaccurate comments based on a too-hasty review of the animation.

    Great presentation.

    A left cross is not always the fault of the left-crosser. In many states, traffic law wisely allows overtaking on the right, but only when it can be accomplished in safety. So, you can’t be cited for it if you do it without conflict, but you can be if a collision ensues.

    This law walks the fence between two worse alternatives. Prohibiting or severely restricting overtaking on the right is unreasonably inconvenient, but allowing it freely, as pushed by facilities advocates, requires that anyone making a left turn or crossing in front of stopped traffic at an unsignalized intersection — bicyclist or motorist — have Superman X-ray vision or else creep forward at 1 mph, blocking oncoming traffic, to give right-passers sufficient warning.

    • Eric
      Eric says:

      “Prohibiting or severely restricting overtaking on the right is unreasonably inconvenient, ”

      Something that I never hear mentioned when passing cars on the right is what happened to a friend of mine many years ago . . . Passenger car door opening. He was going down hill at the time so he had some steam on.

  5. Mighk
    Mighk says:

    Yeah! The revised animations make it even better. Putting those stops in makes it much easier to take in all that information.

  6. atom
    atom says:

    Here is a similar issue with poor (unassertive) lane positioning, but it seems like another form of “screen” that hides the bicyclist from other traffic –

    Here in NZ we drive on the left, and the steering wheel is on the right. That video was shot with a helmet camera about 2m above the road, in the center of the lane, with a fair bit of room behind the van (a car driver’s view would not have the advantages of height or lane position that the helmet camera has) – the bicyclist in front still makes herself completely invisible. From a car, the cloak of invisibility would also happen next to vehicles smaller than a van.

    Get in front, or stay behind… DON’T put yourself on the side.

  7. Ian Brett Cooper
    Ian Brett Cooper says:

    Great graphic. I just linked to this to illustrate the recent deadly collision ( on Christophe Columb Avenue in Montreal.

    Christophe Columb has a segregated bicycle path, yet the left cross still happened. I wonder if it would be possible for this graphic to be updated with an example of how cyclists on a segregated bike path could avoid this? I’m not sure it would be possible, except perhaps by taking one’s bike out of the bike path and joining the road before the intersection.

    • Eric
      Eric says:

      That’s exactly what happened to me in Germany when I was using one of their segregated bicycle paths. The path was along a 4 lane street with about 10 feet between the path and the street. Lots of shade trees and other vegetation.

      The only difference was that my close call was at an uncontrolled intersection. The car was supposed to yield to me, but he didn’t look that far over and even if he did, the trees and shrubs were hiding me. I wasn’t looking way over there, either, but as he entered my peripheral vision, I slammed on brakes and I stopped before we collided.

  8. Khal Spencer
    Khal Spencer says:

    Even good lane positioning is not a cure for left crosses, so always be watching oncoming traffic and look for clues someone might turn, such as a motorist slowing down as they approach an intersection. Cyclists need to use the Motorcycle Safety Foundation concept of S-E-E (scan, evaluate, execute) in order to increase their situational awareness and preparedness to react to bad stuff happening. Keri, does Saavy use something like the SEE concept?

    Motorcyclists, who are bigger, more visible, usually fully occupying the lane, and often running with a headlight on, are often victimized by the “I didn’t see you” excuse. I’ve dodged a few bullets. So by all means follow Keri’s advice, but DON’T EVER get complacent.

    My stepdad did once–riding past a parking lot on his right on a main street on his BMW motorcycle, he reached down to fiddle with the gas petcock, and looked up just in time to T-bone a left turning motorist turning into the parking lot from the oncoming lane. He spent months recovering.

  9. Ian Brett Cooper
    Ian Brett Cooper says:

    That is excellent advice, Khal. I have never heard of the SEE concept before you brought it up the other day in a different forum, but after looking it up, I see it’s similar to the process I’ve used for years. I will have to study it more closely to see what more I can learn from it. Thanks for bringing it up!

  10. Hoppy
    Hoppy says:

    Good article. Here are some things I do when approaching intersections and seeing someone who looks like they want to do a left-hand turn in front of me:
    1. Try to sit up as straight as I can, simply so they can see me better than they would if I’m in a tuck. Also, my actual movement may get their attention.
    2. At night, when I have a headlight, I’ll turn my handlebars back and forth a tiny bit, not enough to actually change my course of directions, but I think that seeing the light move around (as opposed to staying in a stable beam) will make me more visible.

Trackbacks & Pingbacks

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  2. […] These animations will focus on roadway cyclists only. Sidewalk cyclists face this crash more often than roadway cyclists because they are less visible and relevant to motorists. PLAY ANIMATION […]

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  6. […] with mindfulness and proper lane positioning.  Here’s a fantastic animation that shows some common left-cross scenarios and how to prevent them. […]

  7. […] Animation: Preventing the Left Cross for more detailed […]

  8. […] but I hate the idea of a blog post without pictures…. Oh yeah, here’s a still from an awesome animation from commuteorlando about how to avoid the dreaded “left cross.” For real, you should […]

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