RCB S1 17MM MASTER BRAKE HYDRAULIC CLUTCH FORGED LEFT HAND HD TITANIUM

RCB S1 Series Forged Master Cylinder 17mm (LH) stands at the absolute pinnacle of RCB’s professional racing control lineup. Engineered for elite-tier tracking performance and heavy heavy-duty setups, this premium radial pump matches maximum hydraulic force with beautiful structural aesthetics.

Finished in a highly sought-after, premium HD Titanium hard-anodized treatment, this variant features an oversized 17mm piston bore. Crafted using an advanced structural forging process, it is explicitly built to power demanding, high-displacement hydraulic clutch setups on large-capacity sportbikes and adventure cruisers, or to provide razor-sharp actuation for complex left-hand rear brake conversions on racing machines.

Key Features

• Oversized 17mm Radial Pressure Architecture: Unlike traditional axial setups, the S1 features a pure radial configuration where the piston pushes directly in line with the lever’s natural travel path. The massive 17mm diameter moves an incredible volume of fluid with minimal lever displacement, ensuring absolute rock-solid pressure structure and instant mechanical bite.

• High-Density (HD) Titanium Anodization: The entire exterior shell is sealed with a highly specialized, military-grade HD Titanium hard-anodized layer. This treatment provides maximum shield protection against chemical corrosion from aggressive DOT racing fluids, heavy UV surface bleaching, and surface abrasive scratching.

• Monoblock Forged Aluminum Body: Instead of standard cast construction, the S1 pump body is hammered out under extreme pressure into a uniform molecular structure. This forging process eliminates interior air pockets and micro-porosity entirely, ensuring the master cylinder housing will never flex, swell, or distort under panicked, heavy emergency application.

• Oversized Bracketed External Reservoir Tank: Outfitted with a true racing-spec, smoke-tinted fluid reservoir canister securely isolation-bracketed away from the main assembly. This configuration isolates your fluid capacity against engine vibration and structural heat soak, while letting you audit fluid level clarity at a glance.

• Indexed Multi-Position Distance Tuning: Features a tactile click-wheel adjuster integrated directly onto the lever axis pivot. It allows you to micro-adjust the starting reach of the blade closer to or further away from the handle grip, delivering custom-tailored finger ergonomics.

• Collapsible Mechanical Folding Blade: Engineered with an anti-snapping hinge point. In the event of a high-speed track low-side, garage tip-over, or tight lane-filtering wall clip, the main lever arm hinges cleanly upward to absorb the impact energy rather than snapping off at the perch, allowing you to ride onward.

Technical Specifications

Elite System Performance

• Heavy Hydraulic Clutch Systems: Perfect for high-horsepower multi-cylinder superbikes and cruisers (e.g., Royal Enfield Interceptor 650, Kawasaki Ninja/Z series, KTM Duke/RC 390/790) using heavy-duty racing clutch baskets. The 17mm hydraulic ratio cleanly and fully disengages strong multi-spring configurations with significantly shorter lever throw, delivering crisp, instantaneous gear transitions.

• Pro Left-Hand Rear Brake (LHRB): For track racers, stunt riders, or adventure enthusiasts moving the rear brake control off the foot pedal onto the left handlebar, the 17mm radial piston displaces plenty of fluid to drive dual or four-piston rear calipers instantly, providing sharp, high-fidelity trail-braking control.

Installation Guidelines

1. Drape Comprehensive Isolation Towels: High-performance brake fluid acts as a harsh, highly destructive solvent. Completely cover your handlebars, fuel tank shroud, and plastic dashboard gauges in heavy towels to isolate against accidental splashes.

2. Verify Banjo Bolt Matching: The S1 fluid inlet requires an M10 x 1.25mm thread pitch banjo bolt. Using an incorrect thread pitch bolt (such as an OEM M10 x 1.0mm) will cross-thread and instantly strip out the aluminum housing threads. Always build using the fresh copper crush washers included.

3. Perform Symmetrical Radial Bleeding: Air naturally collects inside the elevated top corner of radial master cylinders. Before attempting to bleed down at the slave cylinder or brake caliper, pump the lever slowly a few times and utilize the integrated master cylinder bleed nipple (or slightly crack the top banjo bolt) to purge all trapped air from the primary pressure chamber first.

4. Set Level Reservoir Tracking: Adjust the external reservoir bracket arm so that the fluid cup tracks completely level and parallel to the ground when the motorcycle is held upright and straight, ensuring the internal intake port stays fully submerged.