The Back and Forth on Side-by-Side Riding

Safety Corner logoWhen should cyclists ride side-by-side, and when should they ride single file? This is a hotly debated topic among cyclists. Side-by-side riding allows cyclists to communicate more effectively—not just for socializing, but to provide directions, warnings, and instruction. Also, there are times when it is safer for cyclists to intentionally occupy the travel lane, and side-by-side riding often an effective way to accomplish this.

Single-file riding, on the other hand, reduces the chances of cyclists side swiping each other, provides more leeway to swerve around road hazards, and often allows motorists (and faster cyclists) to pass more easily. Single-file riding is also the law in Massachusetts (except when passing).

Many cyclists ride side-by-side when no traffic is approaching, and then single up whenever traffic approaches to facilitate passing. Many see this as a reasonable compromise. After all, when there’s no motor-vehicle traffic, cyclists aren’t impeding motorists regardless of road position.

However, singling up when traffic approaches is only effective if: 1) cyclists notice approaching traffic right away; 2) cyclists quickly and safely get into single file; and 3) once single file, the line of cyclists is not so long that the motorist still has difficulty passing safely and easily. Noticing approaching traffic is not easy. Cyclists often cannot hear approaching motorists. A mirror works well, but only if the rider remembers to check it every few seconds. Looking back works in theory, but again, must be done every few seconds. It helps if cyclists near the back call out “car back” as a reminder to single-up, but it is still the responsibility of each cyclist to keep track of approaching traffic.

Even if cyclists notice approaching traffic immediately, it can take time to get into single file. There simply may not be enough space for everyone. There’s also an increased risk of collision as cyclists attempt to merge, at a bad time to crash (i.e., when a motorist is attempting to pass). The bigger and more bunched the group, the longer it takes to single up.

So, how should we, the CRW, deal with this matter? Keep riding groups small (six or less—eight at an absolute maximum). A large group is difficult to pass even when riding single file. Smaller groups can also get into single file much quicker when traffic approaches (if not already riding single file). If you find yourself in a large group, suggest to your fellow cyclists splitting into smaller groups.

If your group chooses to ride side-by-side at any time during your ride, please:

Remember—safety is about choices. What choices will you make?


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