There is a great accessory for your bike called a bike computer or cyclometer. Like a cars dashboard it can tell you many things about your speed, average, time and even get into more detailed things like cadence*, heart rate or incline. The computer works on your bike by either a cable running from the computer head unit on your handlebar/stem area down your bike to a sensor that zip ties on. Then a magnet is placed on your wheel, every time the magnet spins past the sensor it sends a transmission to the computer head. It computes how many times per minute or second the magnet goes around, does some math and tells you your speed/distance. The wheel diameter is very important as that is part of the calculation to get the right speed/time so make sure to set your computer head unit for your wheel and tire size. If you change tire sizes, reset the settings.
There are many ways to separate computers, especially if you start getting in to a lot of data capturing. For this article we will start basic, wired or wireless.
Wired Versions :
Entry Level :
Basic featured include speed, time and average speed. Utilizing a cable that runs from your handlebars down to your front fork on the bike. They range from $24-35 and many type or colors are available. The Trek 6i and Cateye Mity 8 are my picks in this category. For this category, go down to your local bike shop and buy what they recommend. This way they are familiar with set up if you need any help at all.
Intermediate Level :
There are a variation of computers between $40-80 depending on what features you need. Some tell temperature, two wheel sizes if you have two bikes, others have a back light and larger numbers. The Trek 9i and Cateye Enduro are top sellers. The 9i tells temperature and the Enduro has a thicker wire for mountain biking.
Take all the features from above but take the cable and have the wire run down your bike to your rear wheel. It also adds a second magnet to track how many times per minute your left pedal goes round. This is called your cadence and can be very important in good riding technique or leg rehabilitation. Also can be used on your trainer as they use rear wheel speed, not front.
Wireless Versions :
Each of the wireless computers come in different variations, the same as above. Adding additional cost for the feature of being wireless, better looking and minimal looking. For a long while these wireless computers got a bad wrap for excessive battery wear, and cross talk (picking up your friends data riding next to you.)
Starting out around $45-50 you can find a great variation of wireless computers. Check out the Cateye Strada or Knog N.E.R.D for stylish and simple. The N.E.R.D is not the cheapest, but looks amazing on your bike and was recently featured on Wired.com.
From $80-120 these aren’t cheap, but to me are worth every penny. No more wires running down your bike frame to your rear wheel. They can be bumped and make sure they can’t spin in to your spokes if bumped. Cateye Strada Double Wireless is by far my favorite. (Are you seeing a trend?)
Lately more computers are coming out, like the Knog N.E.R.D that adds a little bit of fun or playfulness to the electronics on your bike. My favorite is the Trek Time computers. Available for children or adult bikes, and in standard computer features or as a basic analog clock you can accessorize any bike with all the colors they have out. I used the analog version all last year so I wouldn’t miss my bus schedule.
There are many other other computers out there. Heart rate, GPS and so on. We will touch on most of these sooner or later but if you have more immediate questions feel free to drop a comment or email my way!