Brembo GP4-RS Caliper vs Nowaskey Six Piston Radial Caliper

The Brembo GP4-RS is the stronger caliper: a cast monoblock with MotoGP-derived fins, 10% lighter than the M4 One-Piece and 30% more fin surface for cooling, and owners report genuine Brembo parts with precise, strong braking. The Nowaskey is a six-piston billet caliper aimed at converting Harley front ends to radial mount, with differential bores and a dual-bridge body, but it has little independent owner feedback. Buy the Brembo for a 108mm sportbike front end used hard on road and track; buy the Nowaskey if you ride a Harley and want a radial six-piston upgrade.

• Choose the Brembo GP4-RS if you have a 108mm radial-mount sportbike front end and want a proven, lightweight monoblock with real track pedigree.
• Choose the Nowaskey if you ride a Harley with a stock axial front caliper and want to move to a radial six-piston setup.