If you want to keep track of as much data as possible, the SmartCadence is one you can't miss. Make sure your cadence is on the right speed and train your body the way you want it. Keep control over all the aspects of your ride. The only thing you have to do is keep those legs rolling!
To keep track of your speed while riding your bike, your computer can probably use its GPS system, but to make sure you got the right data everywhere at any time, the SmartSpeed will help you. Attach the SmartSpeed easily to the axle of any wheel, and connect it with your ANT+ computer. Easy and fast accurate data!