There's lots of threads on here about finding the right mirror, but having never even considered one, I wondered - why use a mirror?
Obviously it's to see behind you, but I wondered why you might feel the need? We don't have blind spots like cars. There's probably loads of reasons I've not even considered, and of course I'm not saying they're good or bad, I'm just intrigued!

I don't have one. I usually look to the left, and behind, but can also look to the right and behind as needed.

There is a tendency for the bike to pull in the direction one is looking, which may take some practice to overcome.

I tried a bar mounted mirror for a few minutes, but I figured that was easier just to look behind myself than look down at the bars. I have considered a helmet mounted mirror, but haven't quite found the right one.

I'm constantly looking behind me. I look behind me before crossing every driveway and cross-street to check for possible right-hook situations (left-hook situations in the UK.) I also check before changing lanes.

I get by just fine without a mirror but others don't, so a mirror helps.

For some reason my girlfriend hates looking back, so I've considered getting a barend mirror on her stoker bars, so that I don't have to do all the traffic checks when we're riding the tandem.

A mirror is an absolute necessity for me when riding recumbents.

I use a mirror because it tells me the whole story of what's going on behind me. I use the mirror that connects to my helmet and I love it because it's simple and I don't drift out in the lane which happens to most using bar mirrors.

They're more useful in group riding situations, when you have someone's rear tire 6" from you it's risky looking back over your shoulder. Also that tendency to drift L or R is dangerous on a tight 2 lane road.

+10 to replies #'s 4 and 5, but -5 to replies #'s 1 and 2; however,

Serously!?

Riding FRAP, and the road narrows, I want to plan ahead before moving left into the lane.

The same, when I need to cross one lane to the left turn lane I like to look for gaps ahead of time.

That's it for me. Looking for gaps ahead of crossing lines of traffic. You get used to the extra convenience of the mirror and then it's uncomfortable to ride without it.

For riders with less flexibility in the neck mirrors are helpful. My suggestion would be to get a helmet or glass mount mirror. Every morning I climb a bridge with a narrow bike lane and passing riders with wide flatbars plus an extra 6" for mirror is awkward.

An observation: most of the riders I pass on the bridge who have mirrors don't appear to look in them as I always have to say something to get by.

I have bar-end mirrors on my drops. They aren't very useful, since I have to drop my head to see them, and they don't provide a very wide field of view. They are a pain to get set in the right spot, and like to ride in the drops, so I tend to knock them out of position pretty quickly. I haven't even bothered using them most of the summer since it seems a lot easier just to glance over my shoulder than to drop my head to see the mirrors.

What do people do for drop bars? I don't know of a better option, aside from a helmet mounted mirror.

Before I got a mirror, I would look over my left shoulder to see if a car was in the lane to my left, think about switching lanes, look again and suddenly there's a car right next to me. The drivers in this area can drive so fast that a car can seemingly appear out of nowhere between two consecutive looks over my shoulder.

That is why I got a mirror.

Here's a copy of my post from a thread titled "Seeing behind me" :

A glasses mounted mirror lets your vision sweep across the whole view behind, with just a slight turn of your head. It's unnoticeable when looking ahead, after a ride or two. A few years ago, I was walking down the hall at work, heard an odd noise behind me, and without thinking, turned my head to use the phantom "mirror" to see behind me.

I've never used a bar end mirror, but it's field of view must be pretty small, and some are convex, so "objects are closer than they appear"

Even with a mirror, I'm still regularly surprised by cars passing. Unless they have loud tires, I don't hear them due to wind noise, and I have to move my head a little to see behind, so I don't do it continuously.

I don't think mirrors are a solution for texting drivers. Last weekend, I watched 3 or 4 (non-texting) drivers stay in the lane, on a course to miss me by just a foot or two, and wait until the last seconds to move over the center line. They all actually passed with 4 or 5 feet of clearance, but it's really annoying.

My main mirror uses:

--Keep track of other group riders. Are they falling behind, or right on my wheel?

--Left turns in the city. It's great, I can keep track of a break in traffic to smoothly slide over to the left lane.

--Taking the lane in the city, well away from parked cars. If nobody is stuck behind me, I'll ride in the left tire track.

--"Managing" passing cars. On country roads, there's normally not too much traffic. So I've gotten in the habit of looking in the mirror if a car is ahead, coming in my direction. I don't want to be surprised by cars trying to pass with oncoming traffic. I'll move out into the lane to "block" a car behind if I think they will be trying to pass right when an oncoming car is in the other lane--and then I can see if the car behind is actually slowing down.

I'll do the same thing, take the lane, when sharp blind turns are right ahead. Drivers can be really dumb when passing.

--Riding out in the middle of the lane when I have the road to myself. I can get away from the right side of the road, away from torn up pavement, when there's no cars visible behind. That can be much smoother riding.

--avoiding potholes and torn up roads. Can I safely move over to the center of the road?

--Tracking cars way back. If I happen to see a car way back in the distance, I can easily keep track of it. Some of them need a helping wave to get them to pass even with good sight lines.

why use pedals?

Those are the specific reasons I use a mirror, as well, mounted on my glasses.

Also, once in a while, I'll catch a landscaping truck, or heavy construction vehicle towing something in the rear view on a narrow road. I've actually veered on the the sidewalk a few times to altogether avoid a situation with a vehicle like that.

It's my theory that if I ever get clipped on the road, it's going to be by something pulling a trailer.

I tried some different kinds of bar-mounted mirrors with varying degrees of success. Some of them worked pretty well, some of them didn't. Then I tried a "Take-A-Look" mirror mounted to my sunglasses and have never looked back. Well, actually now I constantly look back.

It took a few rides to get used to it, but now I really find it useful. It didn't replace me turning my head and physically looking, but it gives me an additional option. It's especially useful when merging to the left through traffic (i.e. moving across lanes into a left turn lane) where I want to keep an eye on cars both in front of and behind me at the same time.

I still occasionally ride without it, like when I'm wearing goggles instead of my regular glasses. But I prefer having it there.

If someone else doesn't like them, that's OK too.

Oh...and also so I can drop the hammer when I see approaching racers on training runs...

Those guys are usually all about the sneak-attack, so it's fun to mess with them without looking back.

I had a mirror off my bar end a few years ago. It didn't provide much in the way of detail, more so just let me know a car was coming. Could never tell how close it actually was until I wouldn't need a mirror anyway. I always just assume a car is coming up, so I no longer see the point of having a mirror.

I wouldn't ride without one anymore. Like a previous reply stated, it's great when riding in traffic and you need to take the lane and you're watching for that break in traffic. It's great when riding rural roads and there are potholes or debris along the shoulder and you want to be confident that you can veer left into the car lane to avoid them. It's great when riding with others and you want/need to know how far behind they are.

Seriously?

J

I've been commuting for a long time and only recently switched over to using a mirror on my commuter but not on my other bikes. I like it a lot. I rely on my ears mainly to hear traffic but the mirror is a good back up.

I can get along just fine without one, but I can maintain a higher level of awareness with one so the question is why wouldn't I use one. I don't have a single reason not to.

Correct. Most of us look in our mirrors because we are about to do something that requires some information about what is behind. A car coming up from behind usually announces itself with engine and other noises. Cyclists don't. So they come up behind without you knowing. I always assume that a bicycle I am overtaking does not know I am there. And the same when I am the one being overtaken. In any case, a cruising cyclist is not required to do anything to "let you by". Therefore, you technically don't have to alert them. It is a courtesy. It might prevent an accident if they change position while you are close alongside. But you shouldn't be passing so close that 6" of bar end mirror creates a problem for you. Just saying.

Another con of bar mount mirrors is when you're on chipseal, you can't see anything in them.

More information is better than less.

I haven't had the problems with my bar-end Mirrcycle mirror that others have reported with their handlebar mirrors - no extreme shaking, I can clearly make out what vehicles are coming up from behind, etc. And yes, the mirror has proved useful for detecting other cyclists silently coming up behind me. I'm sure some of them feel sheepish when I suddenly say to the almost-drafter behind me "Go ahead" or "Hey, I'm going to turn right/left here" when I'm descending and have to use my brakes (thus hand signaling is not possible).

That all said, I'm probably going to lose the Mirrcycle when my swept handlebar is replaced with a trekking bar, because the bar ends will be facing inward instead of outward. I'm probably going to order this helmet mirror as a replacement - it's not glued to the helmet like other helmet mirrors, which I quite like.

HubBub Helmet Mirror | HubBub Custom Online