Unless your workspace is as clean and brightly-lit as an operating room, some things can be hard to see. Maybe the hardest to see is that thin sliver of space between your rotor and your pads. When adjusting your caliper and straightening your rotor, tolerances are tight. Our simplest Bike Hack yet uses a white sheet of paper to add the contrast you need to see where you're rubbing. Just set the paper on the floor with your caliper in the line of sight, and you'll see the light. Correct, we’re telling you to follow the light. Not really, but the Bike Hack sure helps.