If you've been on a biking trail in the last few years, you've probably seen all kinds of crazy-looking bikes. If you've read "How Bicycles Work," you already know the basics, so in this article we'll take a look at some of the new stuff on today's mountain bikes, including:

  • More gears (Some bikes have as many as 27!)
  • Advances in sprocket technology that make changing gears easier
  • Shift levers that automatically go up or down one gear at a time
  • Front and rear suspension
  • New frame designs and materials
  • New brakes, including hydraulic disc brakes

Mountain bikes are very popular and boast some pretty cool technology.

In this edition of HowStuffWorks, we'll take a look at all of this new high-tech gear. Let's start with the gears.