R-Line
Race Caliper

Powerbrake’s R-Line 6-piston off road race calipers have a championship-winning heritage dating back to the launch of our 1st generation R-Line calipers in 2009. During the decade following their launch, our 1st generation R-Line race calipers won multiple National Off-road Championships, won two FIA Cross Country World Championships, finished on the podium at the infamous Dakar Rally six times and won the Dakar Rally overall in their final year of service in January 2019. Our current 2nd generation R-Line calipers were launched in September 2019 and won the first FIA Cross Country World Championships race that they were used in (Rally Morocco) in October 2019. The calipers then went on to finish the 2020 Dakar Rally in a very close 2nd place in the overall standings. Our R-Line off road race calipers offer an unbeatable combination of performance, durability and reliability all at a competitive price point.

Powerbrake R-Line off road race calipers (both air and liquid-cooled variants) are designed around a common 6-piston race pad profile that is readily available in a wide range of race pad compounds from all of the world’s leading race pad manufacturers. In addition to this we offer a comprehensive line of Powerbrake branded race pads that are manufactured for us by one the very best (if not the best) race pad manufacturer on the planet. After decades of testing race pad compounds both on-car and using state-of-the-art brake dyno’s, we believe that the specific race pad compounds that we have selected to include in our range are the best off-road race pads currently available on the world market..

Powerbrake R-Line race calipers (both air and liquid-cooled) are designed to be used with 320x33mm discs. Be sure to have a look at our R-Line race disc. An advanced 68-vane, directional disc specifically designed for off road race applications. We can also quote on supplying complete 2-piece disc assemblies (including billet aluminum hats and mounting hardware – all manufactured in-house in our factory) manufactured to customer specifications.

We offer two different R-Line off road race calipers. Our standard (air-cooled) 6-piston R-Line caliper (part no: R6IS) and our advanced (liquid-cooled) 6-piston R-Line caliper (part no: R6ISW). Both calipers share most design elements and features and both are designed around the same pad profile. The liquid-cooled caliper allows for liquid to be circulated through the caliper body using a separate circuit, away from the brake fluid. The liquid then circulates through a cooler and then back to the caliper in a closed circuit. The liquid-cooled caliper also accepts an M8x1mm temperature sensor that can be used to provide temp data back to a management system. We generally supply our standard R6IS calipers for lighter race cars or mid-pack FIA T1 class cars. Our liquid-cooled R6ISW calipers are typically supplied to leading FIA T1 teams and Dakar Rally teams.

Our R6ISW race caliper features and advanced liquid-cooling system. Coolant enters and exits the caliper through M10x1mm inlet and outlet ports that are positioned on the caliper at an angle that optimises hose routing. The coolant is pumped through the caliper by a compact, lightweight pump. It then flows over a series of internal cooling vanes that maximise surface area contact with the coolant. Heat transfers to the coolant which is then pumped out of the caliper through a small cooler before returning to the caliper in a closed loop system.

The fluid inlet on our R-Line (liquid-cooled) caliper is situated on the bottom of the caliper and features and is designed to provide support / protection for the neck of the banjo fitting and to prevent the potential loosening of the banjo that can occur as the result of rock impacts.

Our liquid-cooled R-Line race caliper features an M8x1 port that accepts commonly available motorsport temperature sensors. This allows the user to feed real-time caliper temperature data back to their management system, which can be programmed to start and stop the pump used to cycle the coolant at specific temperatures.

At Powerbrake, we believe strongly in the benefits of machining our race calipers from solid billet. All of our championship winning X-Line and R-Line race calipers are machined from high-grade aerospace aluminum billets. Machining from billet is admittedly an expensive way to manufacture calipers but it results in a finished product that exhibits exceptional levels of strength and rigidity. How do we bring our billet R-Line race calipers to the market at such competitive prices? Through significant investment in state-of-the-art 5-axis CNC production equipment that allows us to machine the calipers with maximum efficiency. The fact that we machine all of our calipers from billet, matched to the FEA enhanced caliper designs themselves, results in calipers with an impressive rigidity to overall size ratio. The slim profile of the calipers reduces un-sprung weight and aids with wheel clearance.

Powerbrake R-Line race calipers all feature castellated stainless steel pistons. The castellations allow the super-heated air in the piston cavity to escape, hereby reducing heat transfer to the seals and brake fluid. Our R-line pistons feature recessed cut-outs in the base of the piston to accommodate the anti-knockback springs that are employed in all of our R-Line race calipers. Stainless steel is significantly more expensive to manufacture caliper pistons from than the aluminum pistons used by many of our competitors but the benefits are well worth the investment.

Stainless steel transfers heat far slower than aluminum. The result is that stainless steel pistons slow the transfer of heat from the brake pads to the calipers seals and brake fluid, hereby reducing the chances of boiling brake fluid and also extending seal life. Our caliper pistons are manufactured by a special grade of stainless steel that is more than twice as strong as regular 304-grade (in terms of yield and ultimate tensile strengths), while maintain the same levels of corrosion resistance.

All Powerbrake R-Line calipers feature anti-knockback (AKB) springs in all caliper bores. These specially designed springs are located in machined recesses behind the pistons. They reduce piston knockback that can be caused by the extreme vibrations experienced by the caliper, pads and floating discs under off-road race conditions. This results in a firm, consistent brake pedal for the driver over the widest range of operating conditions.

All Powerbrake R-Line race caliper feature ultra high-temperature seals that are manufactured for us in a proprietary seal polymer. Our seals material has proven time-and-again to remain stable and last longer than our competitor’s seals, especially at extreme operating temps. Our pressure seals are are laser marked and 100% inspected for dimension as well as being visually inspected under magnification prior to fitment into our calipers. In addition to our unique pressure seals, all our R-line race calipers feature internal wiper seals that keep dirt and debris from the critical pressure seals. This significantly improves seal life and increases the service life between caliper re-builds.

Our R-Line race calipers feature internal fluid crossovers and hidden (recessed) bleed screws for protection against damage from rock and stone impacts. Every part of the R-Line race caliper is designed from the ground up to ensure maximum durability and consistency under heavy duty off-road race conditions.

All Powerbrake R-Line race calipers feature our MTR system. The system provides a permanent record of the maximum operating temperature reached by the caliper. Feedback from our race customers has been extremely positive with regards to the MTR system over the years. Customers will really appreciate this feature as it provides valuable data in the support of decisions such as pad compound choice and brake fluid choice. The inclusion of a Max Temp Recording system on a race caliper at no extra charge is unique to Powerbrake on the world market.

The high-tensile caliper cross-bolts used in the assembly of our R-Line race calipers are European sourced and coated with a zinc flake coating. This coating offers exceptional corrosion resistance, while having no negative effect on bolt strength at all. The bolt positions of our R-Line race calipers are the result of extensive FEA analysis and deliver optimum caliper rigidity. The cross-bolts are inserted into the caliper from the inboard side resulting in maximum wheel clearance at the outer face of the caliper.

Powerbrake R-Line calipers feature stainless steel pad rails that are incorporated into the caliper bridge. These protect the aluminum bridge from damage that can result from pad vibration under off-road race conditions.

Our R-Line race calipers are all finished with a Dark Grey (type-3) hard hard anodize. This finish is used exclusively for our R-Line calipers as it is the most durable finish available for off-road race calipers that are subjected to extremely harsh operating conditions.

Our logos and other markings are applied to our calipers using advanced laser technology. This creates a clear visual contrast between the logo and the dark grey caliper finish. The logos on our R-Line race calipers will not be damaged by heat, brake fluid or solvents, as is the case with paint in-lay logos used by many of our competitors. Off-road race calipers operate in a very challenging environment. They are exposed to dirt, stone impacts, carbonised brake pad material, extreme temperatures and constantly changing environmental conditions.

All other caliper hardware components (including: pad abutments and bleed screws) are manufactured from stainless steel to ensure highest levels of corrosion resistance.