Courtesy Gap Equals Deathtrap

This article is written by John Duggan and originally appeared in Bicycle Paper's 2013 NW Tour Guide.

The video below was not part of the original article but graphically depicts the issue. 

CAUTION: due to the graphic nature of this video, viewer discretion is advised.

As I have written about many times before, negligent left turning motor vehicle drivers are responsible for more than half of the bike versus car incidents that I investigate. In most of these situations, the cyclist is not on the driver’s radar screen and the motorist simply looks right through or past the rider without actually registering the bicyclist’s presence. The ever-growing miles of dedicated bike lanes and sharrow lanes have added a new wrinkle to the “left hook” incident. I call this dangerous situation the “courtesy gap deathtrap.”

As you probably know, in most jurisdictions cars and bikes are subject to the same traffic laws and are supposed to share the road. Dedicated bike lanes, however, are exclusively for cyclists and cars cannot drive or park in them. Motorists can turn across them, but only after yielding the right-of-way to cyclists. The courtesy gap deathtrap scenario arises most often when riding during peak commute times when motor vehicle traffic is stop and go.

Assume that you are pedaling northbound in a dedicated bike lane on a busy arterial street. While motor vehicle traffic is crawling, your lane is wide open and you are able to cruise along at 15 to 20 mph while chuckling at the motorists going nowhere — this is one of the benefits of cycling. See Diagram A above. Unbeknownst to you because your view is obstructed by the stopped or slowly moving automobiles to your left, a car approaching from the opposite direction (southbound) is stopped and is waiting for traffic to clear so that it can turn left. A short distance ahead of you, a northbound car stops to create a small opening — a courtesy gap — and then waves to the driver waiting to turn, signaling that it is OK to do so. Although the left turning car has a duty to yield to all oncoming vehicles, including bicycles, before executing a left turn, the driver in this example assumes it is all right to proceed because the nice motorist who opened up the courtesy gap just waved him/ her through. Unbeknownst to everyone, including you, the driver who opened the gap, thinking he was doing a good deed, really created the perfect storm. As the left turning driver travels through the opening with potentially no visibility of the bike lane, he/she T-bones you. Although just moments before you were relishing how great it was to be smoothly rolling along despite the heavy traffic, you are now bouncing on the pavement. This situation rarely ends well for the cyclist.

A corollary situation to the above example is the “right hook,” which occurs when you are traveling along in a dedicated bike lane and one of the motor vehicles that is stopped or slowly moving to your left becomes impatient and abruptly (usually without signaling) attempts to make a right turn directly across your path. See Diagram B.

When riding in a bike lane while traffic to the left is either stopped or slowly moving, cyclists need to be hyper-vigilant. This is another one of those situations where just because the law says you can go “X” miles per hour, it does not mean that you should. As in most situations where bicycles and cars are sharing the roadway, ride defensively and assume that an automobile could abruptly attempt to turn across your path. If you see a gap open in the traffic or if there are driveways or cross streets along your path, proceed with extreme caution. The greater the motor vehicle congestion, the slower you need to go so you can take evasive action when necessary. Remember, an ounce of prevention is worth a pound of cure and may save your body and your bike.

Ride safely!

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