Be in the bike lane

Most of the same reasons why bicyclists will drive towards the center of a lane are good reasons for leaving the bike lane. Even in states with mandatory bike lane use, the law allows cyclists the same exceptions as it does to keeping right in general. Here are just a few reasons:

• Bike lanes collect the debris and glass that is swept off the road. Sometimes you can see it because it’s big, like tree branches, but sometimes only we can see it. A small shard of glass can cause a flat tire. (How many tires did you change on your way to work today?)
• Many bike lanes are designed poorly or just plain dangerous. Bike lanes next to parked cars are often entirely within a hazard area we call “the door zone.” A suddenly-opened door can kill a cyclist.
• When approaching intersections, or in areas with lots of driveways, a bike lane puts us in a conflict zone (shown in the above animation). Bike lanes increase our risk for all of the common crossing and turning crashes.
• It may not be a bike lane. It has become popular to add edge lines several feet to the left of the curb. This space is substandard and not safe for a bicyclist to use, though many bicyclists are tricked into riding there.

Many of the reasons we avoid bike lanes are not visible or apparent to a person in a car. Of course, if a bike lane provides a clean, safe place to ride, we use it.