What is difference between platform pedals and clipless pedals?
A platform pedal is simply a platform you place your feet on. When pedaling with a platform pedal you simply press down(forward) on the pedal with your feet. A clipless pedal has a locking mechanism that will snap onto that pedals specific cleat. Cleats are the part of clipless pedals that bolt onto the bottom of a clipless shoe. Clipless pedals allow you to push down on your pedals with one foot as well as pulling up on the pedals with the opposing foot. This means you can push and pull in the same crank rotation, which generates more power and a smoother rotation.
