Gray Triathlon / TT Bike Brake Small Parts

Integrated rim brakes are ideal on dry, flat-to-rolling TT courses because hidden calipers reduce drag and pair well with 35-90mm aero wheel depths. For wet conditions, technical courses, or late braking you’ll get more consistent stopping and modulation from hydraulic discs.

Rotor size affects braking power and heat management, with 180mm offering a bit more stopping and cooling than 160mm on long descents. Rotors like the 6-bolt Centerline XR are available in 160–180mm sizes, so opt for the larger rotor if your course has sustained braking demands.

Thru-axles such as 12mm increase wheel-to-frame stiffness, which sharpens handling and helps disc setups feel more precise under cornering. That added rigidity benefits aggressive TT riding by improving steering feedback and maintaining consistent brake feel.

Brake levers designed for aero base bars or bullhorns position controls horizontally or near-vertical so you can brake from your aero tuck, and extensions put reach where you’re actually riding. Hydraulic units like HRD Road & Level Ult/Tlm mount cleanly to aero bars and keep modulation predictable when you’re tucked in.

Hydraulic discs paired with stainless-steel-backed pads deliver a firmer, more consistent bite and better heat resistance than typical cable setups. Cable brakes can feel spongier under repeated heavy use, while hydraulic pads and calipers provide more repeatable lever feel for race conditions.