Bike computer

Bike computers—sometimes called cyclometers—can provide you with all sorts of information and help you with your training goals. But even basic models will tell how fast you can climb a hill or display your maximum speed. What one is right for you?

How They Work

Most cyclometers use a magnetic counter to determine your speed. A magnet is attached to your bike's front wheel and a magnet pickup is attached to the fork. With each tire revolution, the pickup is triggered. Based on the calibration you set for your bike, the computer in the cyclometer calculates the distance you've traveled, your speed and other measures, depending on the sophistication of the model.

Which Bike Computer Features Do You Need?

The cyclometer you need depends on your training goals. The casual mountain biker may need only a rugged, basic model with current and average speed plus trip and total distance. Someone training for a triathlon or a season of racing, however, is going to want a more advanced model—one with a multiple-ride stopwatch, a cadence measure and perhaps an altimeter. Some high-end models are now GPS-enabled for easy navigation and have a heart-rate monitor for training data.

If you ride a road bike and a mountain bike, there are models available that can be switched between bikes. Consider this option if you regularly use more than one bike.

Some wireless models offer a coded transmission so that your computer doesn't read the signal off your riding buddy. These are good if you ride mainly in a pack, road racing or training. Other models are mountain-bike specific and provide a readout even at a low speed level.

Models available from REI cover the full range, from the most basic and moderately priced to very sophisticated for the elite athlete or competitor.

Shop REI's selection of bike computers.

Bike Computer Features

Here are the most common ones to consider:

Current Speed

This feature is found on all bike computers and can help with pacing.

Average Speed

By slowly increasing your average speed over the same route, you can help increase your anaerobic threshold.

Maximum Speed

Downhill racers benefit most from this feature.

Trip Distance

This info is helpful when following the route described in a guidebook. Knowing your past mileage can also allow you to strategically increase your training loads.

Odometer

Tells you know how many miles your bike has traveled. This is handy for determining when it is time to change out your tires.

Cadence

Measures the number of pedal revolutions per minute, allowing you to choose the optimum gear for pedaling efficiency.

Stopwatch

Putting sprints into your workout can increase overall muscle and cardiovascular strength. Plus, nothing beats a race against the clock to improve your endurance. Some models feature an auto start/stop, so that only your time in the saddle is measured.

Altimeter

Measures the highs and lows of your ride. Useful if you're training for a specific race or to keep an elevation record of your tour.

Clock

Lets you know when it's time to head home for dinner. Some models have alarms, too.

Weight

Most cyclometers are so light that any weight differences are negligible.