• MSRP: $21

Now that disc brakes have infiltrated the road bike world, it’s time to steal a few other things from the mountain bikers — namely, tools to adjust those disc brakes. Hayes created this nifty Feel’R Gage to make centering your brake calipers quick and easy. It’s indispensable for any rider who has made the switch to disc brakes.

When folded, the Feel’R Gage takes up minimal space in your tool box. It would be easy to lose it in the depths of your tool pile, but fortunately Hayes had the forethought to anodize this bad boy purple so you can find it when it inevitably shimmies down to the bottom of the box. The purple portion of the Feel’R Gage also doubles as a pad spreader tool.

Flip out the metal arms and straddle them on either side of your rotor when the wheel is mounted in your frame or fork. Loosen your brake caliper. Then slide the rotor and Feel’r Gage tool forward so the arms fit within your brake caliper. The arms help you center the caliper over the rotor. With the tool inside the caliper, simply squeeze the brake lever to keep it in place, and tighten down the caliper mounting bolts. Your caliper should then be centered for noise-free and rub-free operation, simple as that.

There are, of course, other ways to get your brake calipers centered without the Feel’R Gage, but for $21, it’s worth every penny to have a simple, repeatable way to center your rotors without the guesswork, or the scrap of cardboard from the garage trash can. Best of all, this all-metal tool can live in your toolbox for the long haul, standing up to years of abuse. We’ve even spotted it in pro mechanic toolboxes at the Tour de France, offering pro wrenches the ability to zip through brake adjustments on numerous team bikes daily.