Cycle computers help you make the most of your time on the bike and are a great training tool, they have many functions including speed, distance, maximum speed, average speed and some even feature cadence (pedal revolutions). Trying to keep your average speed a bit higher or finish a familiar route in a new record time will give you the inspiration needed to push harder, get fitter and achieve that goal. If you commute on the same route every day, a computer injects a bit of interest. Cordless computers are easier to fit and look neater on the bike, meaning no messy cables to try and tidy up. If you're serious about improving your fitness, a computer with a cadence function will really help and these often read from the rear wheel, allowing them to be used with a turbo trainer.