Pedestrians can be saved by the bell

Bicycling is the natural transportation choice in Davis. We are lucky to have the wonderful infrastructure that makes biking so easy and beneficial but, as good as it is, it has to be used courteously and responsibly.

Most Davis facilities are multiple-use ones. Greenbelts and bike paths are heavily trafficked by both pedestrians and bikes. We cyclists must remain especially aware of safety because of high speed differentials.

A bike travels about five times faster and has about 25 times more kinetic energy than a person walking. Another exacerbating factor is that bikes are so quiet that walkers can be completely unaware of their presence unless active warnings are issued by the cyclist.

Responsibility cuts two ways. Both walkers and cyclists need to be constantly alert to danger of collisions. Anything that increases this awareness is good. And anything that decreases it is bad.

Bikes typically ride and pass oncoming cyclists on the right, as do automobiles on roadways. But where should walkers walk on bike paths? It seems unquestionably safer for them to walk on the left facing oncoming cyclists, since they can easily see bikes approaching and nimbly avoid them with a quick step to the left. Mutual eye contact is made without turning one’s head and it is considerably easier to discern intent.

Frequently, cyclists overtake slower bikes or walkers, whether on the right or left. Because the overtaken party is facing away from the faster-traveling bike, it is especially important to give them a loud auditory signal since they can’t see us.

Although a concise verbal warning like “On your left” accomplishes this, a more distinctive sound is better. The sound itself can be quickly associated with the image of the unseen bike bearing down on the hearer. Squeezable “Aahooga” horns are picturesque, loud and effective but slower to actuate.

Bike bells do this well and every bike should have one (it’s as important as a light)! Make sure to mount the lever just next to your handlebar grip so only your thumb must be moved, not the whole hand. This can save half a second and may mean the difference between a timely, effective warning and one that’s just a bit too late.

And the louder the better. Cell phones, iPods and other electronic ear paraphernalia crowd the auditory channels of the cyclists and walkers we are trying to alert. Don’t assume just because you warned, either with words or a ding-ding, that the intended recipient of your message actually heard it. Instead, ride defensively.

Be alert for sudden changes by pedestrians in their direction of travel. Walkers can easily turn quickly (and without thinking) from their previous directions, but bikes, with their higher speed and momentum, are less agile. A large part of defensive cycling is choosing a path that allows maximum flexibility if something does change unexpectedly.

In summary, be courteous and smart on our bike paths. Walkers should walk on the left facing traffic, keep alert to oncoming bikes and shouldn’t play songs so loudly that the music is the last thing they’ll ever hear. If you walk your dog, for heaven’s sake, don’t let the leash string out across the path.

Cyclists should ride defensively, give wide berth and warn walkers who can’t see them with words and dings. If you don’t have one, buy a bell. Then ring it! The life you save may be your own!

— Mont Hubbard is a professor of mechanical and aerospace engineering at UC Davis and president of Davis Bicycles! He does research on bicycle dynamics and is trying to increase his bicycle travel mode share.

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1 Response to “Pedestrians can be saved by the bell”

  • Maybe Davis needs to think about having separated bike and pedestrian roads on heavily traveled areas. Speed control devices can also work for bicyclists just as they do for cars. It is important that bicyclists keep their speed low when interacting with and passing pedestrians.

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