The Shimano Ultegra BR-R8100 is a dual-pivot rim brake caliper pair designed for road bikes seeking reliable stopping power. This caliper uses SLR-EV technology, which employs dual symmetric pivots with bearings and a roller to improve efficiency in the pivot area, delivering superior modulation and braking power compared to earlier designs. The 51mm reach accommodates rim widths from 20.8–28mm, supporting tires up to 28mm—useful for riders running slightly wider rubber for comfort. The short-arm brake design provides clear contact feeling and smooth actuation. Each caliper ships with Shimano R55C4 brake pads, adjustable pad carriers, brake nut hardware, and a cable tension adjustment dial for field tuning. At 182g (front) and 180g (rear), the pair represents a practical balance between weight and cost. These are traditional center-mount calipers, not direct-mount, making them compatible with standard road frame brake bosses.