If you are building a track bike or even if it's just time to replace parts in your aging brake system, a new brake caliper will improve your brake performance. New brake calipers will help shave off speed before you dive into turn 1 at your next track day. If you're riding an American v-twin that is not known for stopping on a dime, upgrading the brake calipers and pads will get you a marked improvement over the factory set up. A brake caliper cover will get your ride looking just a bit more custom, but nothing will look as trick as a shiny new set of machined calipers on your ride.