Mine is called a . . . . err , , , , mirror . . . . available cheaply at any drugstore

I use a $12 cheapie from Walmart. It has odometer (critical for randonneuring) and speedometer (critical as a measure of manliness) and that's all I really need.

And how do you improve your pedal stroke? The two exercises most commonly used are One Legged Pedaling, and spin ups. For a one legged pedaling drill, you normally want to maintain a specific cadence, and increase that over time. Spin ups are all about cadence, and maintaining the fastest smooth pedal motion you can. How fast you can pedal without bouncing off the saddle is a basic measure of how well you pedal. My point is that having cadence improves your pedal stroke - much harder to improve it without cadence.

A modern wireless computer with cadence has a single sensor you attach with zip ties, a magnet on a rear wheel spoke (easy as pie) and a magnet you just let stick itself to the end of the pedal spindle. That's it... you are done. Nothing complicated about it. IMO, a computer without cadence (and HR) is likely to be one of those items that ends up in a ziplock in the garage, along with the other "I should have bought the more complete solution in the first place" items.

I rode 7-8 thousand miles last year using a basic wireless with speed, time and distance functions and didn't feel at all deprived. What I felt was more important to me was the heart rate monitor that I had in addition.

Another Protege 9.0 from PB user here. One caution on wireless computers - if you have a battery powered LED headlight mounted near your computer display, you may get some RF interference that would interfere with your computer when the light is on. In my case, the distance seems to be accurate, but speed bounces around all over the place because of the interference.

Cadence is very useful, it is really good to help keep you from pushing too big of a gear, especially when you get tired.

And GPS is great - I was skeptical at first, but I really enjoy looking back at all the places I've ridden over the past three years since I've been using the Garmin (now a 500). You can post on the Garmin Connect site and share for free or if you're more competitive minded, try Strava, which automatically identifies climbs and other segments and compares your ride with other members of the service.

If you have a smartphone, you can probably get a free (or cheap) application that will do the GPS for you (including speed and distance). The only problem is battery life if you ride longer than a couple of hours. Strava offers one of these.

I must add - leaving all this at home occasionally and going for a fun spin around town is probably the best!

I don't know, I have two computers (on different bikes), one has cadence, the other doesn't. I find cadence is much more useful on the bike that goes on the trainer, because it's harder to tell, when cadence is low on the trainer, then it is on the road. I have been riding a bicycle on and off for almost my entire life, saddle time, I think at this point is over 25 years, and I think we make far too much of needing to be training for racing, when it actually doesn't matter. Way to much is made of the perfect pedal stroke, and having to be at exactly the right cadence when "training". Lots of people get way into the numbers and then one day, we nearly all get to the point of realizing that the only thing you really need to track is distance, in order to know roughly when things like chains and tires should be budgeted for replacement. Even that, if your within 100 miles or so, that is close enough, the computer on the mountain bike has been wonky lately, I think there is a loose connection inside the unit, and think it would cost more to fix it, then replace it. I am currently thinking the best thing to do, is to put the sensor on the rear wheel and put the computer on the back of the seat post, because I don't need speed on that bike, I don't need cadence, I just need to know the total distance covered. In some ways I think the best computer for that bicycle would be a simple counter that counts wheel rotations.

The ones I remember were more like the current magnetic/electronic units in that they had a little "trigger" that clamped onto a spoke much like magnets do today and every revolution it advanced a cam on the odometer unit one click. Very much the mechanical analog of today's electromagnetic odometers. I never had one but I did eventually get a speedometer/odometer that was built a lot like automotive units. There was a flexible shaft drive that mounted to the front hub and ran up to the "dashboard". Just as in mechanical automotive units the speed was displayed with a mechanical needle and distance on a cylindrical digital counter. The speedometer was even driven by a magnetic eddy current coupling as in automobiles of the time. Bought it at Sears and I still have it buried in the basement somewhere.

I'm an engineer and like most of the breed I never met a measuring device I didn't like so when it comes to which bike computer features I need the answer is quite simple: I need all of them plus a few that have not been invented yet!

Ken

A wise man over on another forum states "The right bike is the one you will ride!".

I think the same theory applies here. Decide what YOU want and go get it.

As many have stated already, ya don't NEED any computer to ride yer bike!

As far as the Smile-O-Meter is concerned, well I think that is a physically internal thingy powered by fun and calibrated with wisdom. We each have to nuture and grow our own.

You need a bike in order to ride, so yes, the right bike is the one you will ride (or perhaps for many people, the one you would ride the most, since many would ride SOME on a bike that isn't quite right, just not as much).

You don't need a computer to ride, though, and most will ride whether or not they have a computer (if they have the right bike). So a computer is better than no computer if it makes you ride more. If it doesn't make you ride more, then it is all gravy, whatever makes you happiest.

I generally don't ride with a computer, but in my dream world where I get some luxuries, other than speed and distance, the two things I would like to know most are heart rate and the grade of the road, and heart rate would be number one. I can easily live without a computer, so long as I don't get my heart rate so high that I die, and so far, I've only had a few instances where I stopped out of caution because I sensed I'd let my heart rate get too high -- it would be a nice luxury to avoid those times.

And you don't really need a bike computer with a heart rate monitor. Those are also sold separately.

Trust me, my heartrate will never get up that high on a bike