Buying brake pads for both front and rear calipers in a single package saves you a few dollars and means you won't forget to order the second set when the rear pads wear through months later. Shimano's R55C4 2-pair package includes four pad inserts and four fixing bolts, covering a complete refresh of your rim brake system. The R55C4 compound works with Dura-Ace, Ultegra, and 105 calipers spanning multiple generations, so this one box handles most Shimano road bikes built in the last twenty years.

The compound itself came out of Shimano's development work on the Dura-Ace 9000 series. Earlier pad formulations had a tendency to absorb metal shavings and road debris, requiring periodic cleaning with fine sandpaper or an awl to keep the braking surface fresh. The R55C4 resists that contamination, and the segmented grooves molded into the pad surface help channel away water and grime during use. Wet weather braking improved significantly over the previous R55C3 generation, with more predictable modulation when descending in rain.

Each pad slides into your existing cartridge holder and locks in place with the included fixing bolt. Shimano applies a mild threadlocker to the bolt threads, so they stay secure through vibration and repeated hard stops. The installation takes about thirty seconds per pad once you have the wheel off and the brake released. If your current pads still have life but you're stocking up, these store well in a toolbox or saddlebag for roadside replacement.... Read More