Helping Motorists With Lane Positioning
“‘I’ll see it when I believe it’ is more accurate than ‘I’ll believe it when I see it.'”
– Social psychologist Karl Weick
Regular readers of this blog know we recommend an assertive lane position when the lane is too narrow to share. Our rationale was initially that when a cyclist is in the right wheel track, some motorists will still attempt to squeeze past within the lane instead of making a full lane change. That’s still true. But we’ve also observed that a more assertive lane position — either in the center of the lane or just left of center — gets motorists to change lanes earlier on roads with more than one lane in each direction.
Our hypothesis was that from a significant distance, a cyclist in the right wheel track (where the League of American Bicyclists has long recommended cyclists travel if the lane is too narrow to share) looks like he or she is on the edge line, so the motorist stays in that lane until he or she gets close enough to realize there’s not really adequate width for safe passing. By then the opportunity for changing lanes may have closed. The motorist then either waits and stews, or “shoves” his way through between the cyclist and the traffic in the next lane.
When the cyclist is in the center of the lane, it’s immediately clear to the motorist that passing within the lane is impossible, so the driver changes lanes at the earliest opportunity.
The added benefit we’ve discovered using a video camera on the dashboard of a following car is that drivers farther back are alerted to the situation by the lane changers ahead of them, and get to see the cyclist themselves at an earlier opportunity.
Watch the video a couple times. Notice how relatively empty the right lane is when I’m in the more assertive position, and how there are more cars passing closer and staying in my lane longer when I’m in the right tire track.
In the above image: The Lane Control run was westbound on University. (1) marks the camera car position when the driver spots the cyclist, (2) is the cyclist’s position when spotted, the red line indicates the distance needed to slow from 45mph (speed limit) to 15mph (cyclist’s speed), (3) marks where the camera car passes the cyclist. The Right Tire Track run was eastbound. (4) marks the camera car position when the driver spots the cyclist, (5) is the cyclist’s position when spotted. Note: the cars were slowed well below the speed limit by the indecision of earlier drivers and lack of visibility for following drivers.
This is of course only a pair of runs down this road. In order to get truly sound data we’d need many more runs.
If all we wished to do was keep motorists happy we’d ride on the sidewalks, but that subjects us to many more conflicts and hazards.
Imagine if we could help motorists see that the assertive cyclist lane position actually makes their job easier and reduces delay.
These runs were chosen for this video because they had virtually the same traffic count (35 for the Lane Control run and 36 for the Right Tire Track run).
In the Lane Control run 13 vehicles were originally in the right lane, 12 made a complete lane change, 1 made a right turn. There were 22 vehicles in other lanes.
In the Right Tire Track run 17 vehicles were originally in the right lane, 10 did not make a complete lane change (only 3 of those had vehicles near them in the center lane). There were 19 vehicles in the other lanes. Take a look at that last line of vehicles that remained in the right lane. The other 2 lanes were almost completely open. Had they all changed lanes when they spotted the cyclist, they would have been past him 1/4 mile from the intersection and would not have had to slow down.
To see Lane Control in action with much higher traffic counts, see this video of the UCF Bike Bus.