RCB E2 PREMIUM ALLOY REAR BRAKE PUMP CHARCOAL

RCB E2 Premium Alloy Rear Brake Master Cylinder is a high-performance hydraulic upgrade engineered to replace standard factory rear brake pumps.

Part of RCB’s highly reliable E2 Series, this rear master cylinder features a refined 12.7mm internal piston bore housed inside a premium alloy chassis. The Charcoal finish offers a stealthy, modern, industrial-grey aesthetic that blends perfectly with dark swingarms, matte frames, and aftermarket carbon accents. It is designed to minimize foot-pedal play and provide consistent, highly communicative braking pressure.

Key Features

• Precision 12.7mm Piston Bore: Delivers a highly balanced hydraulic ratio for rear braking systems. Unlike oversized pumps that make the rear brake feel like an “on/off switch,” the 12.7mm bore offers progressive, accurate fluid modulation—allowing you to trail-brake smoothly into corners without accidentally locking up the rear tire.

• Premium Cast Alloy Construction: Manufactured from high-grade aluminum alloy with tight casting tolerances. The robust structure eliminates body deflection and pressure bleeding under heavy foot force, ensuring precise hydraulic transmission.

• Hard-Anodized Charcoal Finish: Features an advanced anodized surface treatment that resists corrosion, scratches, and chemical stripping from caustic brake fluid. The matte charcoal tone provides a high-tech look that sits clean on sport, naked, and underbone builds.

• Universal Mounting Setup: Features standard 50mm eye-to-eye bolt hole spacing (slotted for slight adjustment). This universal layout makes it a direct bolt-on or easy-fit upgrade for a vast majority of motorcycle factory rear-sets and aftermarket racing footpegs.

• Highly Resilient Internal Seals: Fitted with race-derived rubber cup seals and an internal return spring that maintains optimal pressure integrity, even when exposed to intense ambient heat from adjacent exhaust pipes or hard-working rear disc rotors.

Technical Specifications

Installation Guidelines

1. Check Remote Reservoir Alignment: The Charcoal E2 pump features a direct inlet barb for an external fluid reservoir hose. Ensure your remote fluid tank hose fits tightly onto the barb and secure it with a spring clamp to avoid fluid weeping.

2. Flush with Clean DOT 4: Completely flush out the old, darkened brake fluid from your rear lines and caliper. Refill the system using clean, high-performance DOT 4 brake fluid from a freshly unsealed container.

3. Bleed the Hydraulic Circuit: Rear brake systems are notorious for trapping air at the highest point of the banjo bolt line. Bleed the system thoroughly from the rear caliper bleeder valve upward until the foot pedal stroke feels firm and responsive.

4. Vibration Defense: Motorcycle foot controls are subjected to constant high-frequency engine vibrations. Always secure the two main mounting bolts using a drop of medium-strength blue threadlocker (e.g., Loctite 242) to keep the hardware safely pinned over long-distance riding.