A charging dog, a ball bouncing into the street with a small child in hot pursuit, a driver rounding a corner or pulling out of a driveway or opening a car door without looking—all are good reasons to swerve your bike into the middle of the street to prevent an accident. (You shouldn’t be riding that close to parked cars, but that’s a matter for another day.) They’re also good reasons to have and use a bike mirror instead of relying on even a quick glance over your shoulder, which eats up precious time and takes your eyes off the road in front of you. Even if you ride only on safe, back streets, you can’t always know what’s behind you in case you need to dodge a rampaging tricyclist. Cars appear as if by magic, especially nearly silent hybrid and electric cars, and they’re no softer for being on the quiet streets in your immediate neighborhood.
Bike mirrors come in three main styles:
Choosing a bike mirror
In my book, helmet and glasses mirrors have it over handlebar mirrors for several reasons:
- Handlebar mirrors are too easily knocked off or knocked out of adjustment if you get too close to something.
- Handlebar mirrors make your bike wider when you need to squeeze through tight places.
- Handlebar mirrors require that you look further away from the road in front of you than helmet and glasses mirrors do.
- What you can see behind you with a handlebar mirror depends on which direction your handlebars are pointed. With helmet and glasses mirrors, you can turn your head and look almost anywhere.
I learned one disadvantage of helmet and glasses mirrors from a friend of mine, who has the occasional migraine headache. She made two attempts to use a glasses mirror and gave up because both attempts were soon followed by migraines. Whether this is a universal problem for folks who get migraines I couldn’t say.
I’ve used both helmet and glasses mirrors, and I strongly prefer glasses mirrors:
- Helmet mirrors are attached with an adhesive that eventually stops adhering.
- Helmet mirrors that bend (like the one pictured above) crack where the stem bends. The one I had of this style lasted a matter of weeks.
- On all of the helmet mirrors I’ve used (three at last count), the place where the mirror attaches to the stem is a really tiny ball-and-socket joint that readily breaks. If you don’t break the mirror first, that joint wears out, and the mirror flops around and points wherever gravity and the wind direct it.
- With a helmet mirror, you can’t just stuff your helmet into a bag with your other bike gear or toss it onto the chair by the back door, or you’ll break the mirror plumb off.
- A good glasses mirror, made of metal and a bit of glass (see the picture above), attaches and detaches easily, is nearly indestructible, and can be readjusted if you happen to knock it out of whack. Beware of plastic glasses mirrors, which aren’t as durable and have the same type of really tiny joint that dooms helmet mirrors.
- Using a glasses mirror gives you a good excuse to wear glasses even if you don’t normally. This helps keep dust, bugs, and other schmutz out of your eyes, and, if you wear sunglasses that give you protection from ultraviolet rays, you’ll help prevent UV damage to your eyes.
One caveat: if the arms on your glasses are extra thin, try a glasses mirror before you buy it to ensure that it’ll hold on securely. After happily using the same glasses mirror for many years, I went through a series of helmet mirrors because I got glasses with skimpy arms, and my old mirror wouldn’t work. Recently I went back to glasses with slightly beefier arms, and I’m again using the old glasses mirror.
Using a bike mirror
If you opt for a helmet or glasses mirror over a handlebar mirror, using it will take some practice. You affix the mirror to the left side of your helmet or the left arm of your glasses, and because it’s so close to your face, you can’t effectively view the reflection with both eyes. (The image that your left eye sees is almost directly behind you, while the image that your right eye sees is off to your left somewhere.) You have to learn to focus on what your left eye sees, and ignore what your right eye sees. Wear the mirror around the house until you’ve mastered this trick so you aren’t concentrating on learning to use your mirror when you should be concentrating on traffic and looming curbs. When I first started using a glasses mirror, it took me the better part of a week to grow comfortable with it.
Regardless of what type of mirror you use, unless you’re dodging an obstacle to prevent a crash and you don’t have time, you should still look over your shoulder before you change lanes or change your position in your lane. Drivers don’t know that you have a mirror and know how to use it, and they’ll be startled and irritated that you didn’t look to see whether anyone was behind you. When you turn to look back, however fleetingly, they can assume you’ve seen them.