Sweet Simplicity No fancy gizmos. No wires. No fuss. Turn your bike into an indoor bike trainer. Whether your training for a local charity ride or working to beat your friend’s FitBit score, the Mag indoor bike trainer can help you make it happen. Simply connect the trainer to the rear wheel of your bike, hop on and pedal away. Plus, the Mag comes with five adjustable levels of resistance so you can adapt every ride to your liking. Want to train with Zwift or Rouvy? The Mag can do that too. All you need is a speed sensor. Visit our setup guide to learn how to get started.