EVO GR4 Four-piston gravity brake for the most demanding applications. Delivers maximum power with no compromise. Super-smooth lever action and premium construction make controlling that power feel natural. The benchmark brake for gravity and e-bike use. One piece machined caliper for reduced weight and increased stiffness Four hybrid pistons allow smooth movement and excellent heat management The largest pistons for the greatest power The larger pistons increase the ratio of the brake by ≈ 6% when compared to Tech 4 V4 brake system Improved caliper stiffness increases power and control Not compatible with vented rotors Revised bore cap design reduces width for more frame clearance Choose this caliper for ultimate power in the most demanding applications The Lever Blade There are 3 different lever blade options. Brakes are supplied with Standard (STD) lever blades, this blade will be the right choice for the majority of users and applications. POWER and CONTROL options are available separately. All EVO blades feature an increased lever hook for greater control and security during aggressive riding and a new dimple design in the finger contact area to improve comfort during hard braking, while still retaining grip in all weather conditions. All blades also allow reach and bite point adjustments. Cam Mechanism A new cam designed to decrease the free lever stroke while maintaining the feel and modulation in the braking zone — a key feature of the Tech 4 brakes. The result is a slightly firmer feel at the bite point, followed by a gentle rise in power through the braking zone, further enhancing brake modulation. Piston Movement Roller bearing main pivot is carried over from Tech 4 along with sliding guide bush on the main piston. Additional secondary guide bush keeps the piston running perfectly straight to maintain super smooth piston movement throughout the full lever travel. Bleeding A bleed port has been added to the master cylinder body to allow bleeding without removing the lid, simplifying and streamlining the process. The classic "open" bleed option is retained for the ultimate bleed. The internal port design has been reworked to eliminate air pockets during bleeding and to support a more consistent bleed process.
