Vance & Hines PCX Big Radius: The Icon Reimagined for the Milwaukee-Eight

Few exhaust systems are as instantly recognizable as the Vance & Hines Big Radius. For the 2018-2024 Harley-Davidson Softail Breakout and Fat Boy, this system has been re-engineered with PCX (Power Chamber Exhaust) Technology. The challenge with modern Milwaukee-Eight engines is balancing the desire for a loud, aggressive roar with the need for backpressure and emissions compliance. Vance & Hines solved this by integrating a high-flow chambered catalyst into the heart of the pipe. This isn’t just a “baffle”; it is a performance-tuning element that increases mid-range torque and produces a deeper, throatier growl compared to traditional open pipes. If you want your M8 Softail to turn heads at a standstill and pull harder through the gears, the PCX Big Radius is the solution.

Precision Fitment for Wide-Tire Softails

The 2018+ Breakout and Fat Boy present a unique challenge for exhaust manufacturers due to their massive 240mm rear tires and specific frame geometry. The Big Radius 2-into-2 is meticulously swept to provide maximum visual impact without interfering with the bike’s iconic wide-stance look. Each pipe is constructed from high-grade steel and features 220-degree full-coverage heat shields. These shields are precision-cut using a plasma arc to ensure a perfect fit, and they are essential for preventing the “blueing” or discoloration that occurs on single-wall pipes. Whether you choose the deep, mirror-like Chrome or the high-temp Matte Black Ceramic finish, your exhaust will maintain its premium look through years of heat cycles.

Expert Tuning & Installation Advice

As V-Twin specialists, we consider the PCX Big Radius the best “visual” upgrade for the Fat Boy and Breakout platforms. Pro Tip: Because the Milwaukee-Eight engine is highly sensitive to changes in exhaust velocity, a high-quality fuel tuner is a must. We strongly recommend the Vance & Hines Fuelpak FP4, which features specific maps designed for the PCX chamber. This will eliminate “popping” on deceleration and ensure your engine runs at the optimal temperature. Installation Note: When installing the heat shields, use a small amount of window cleaner or alcohol on the pipe before sliding the shields on. This acts as a lubricant and prevents scratching the finish. Once installed, wipe the entire system down to remove fingerprints before the first fire-up to prevent permanent staining.

The Signature Vance & Hines Sound

The Big Radius has always been known for its “bark,” but the PCX version offers a more “refined” aggression. At idle, it provides a rhythmic, deep-frequency thumping that perfectly complements the M8 idle. Under heavy acceleration, it opens up into a crisp, roaring exhaust note that reflects its drag-strip heritage. It provides excellent ground clearance for those who like to lean their Softails, making it as functional as it is beautiful. For the rider who wants their Harley-Davidson Fat Boy or Breakout to stand out as a premium custom build, there is no substitute for the Vance & Hines Big Radius.

Fitment Note: Fits 2018-2024 Softail Breakout (FXBR/FXBRS) and Fat Boy (FLFB/FLFBS). Does not fit models with mid-controls. Compatibility with passenger pegs is maintained using the included relocation brackets.

Vance & Hines PCX Big Radius Exhaust For Harley Softail Breakout / Fat Boy

Delivering the best of both worlds, radical custom-bike styling with high quality details like precision-cut full coverage heat shields, Big Radius reset the bar for aftermarket exhaust systems. Now featuring our innovative PCX Technology, which integrates chambered high-flow catalysts for a boost in torque while producing the deep throaty growl you want from your v-twin machine.

Features:

• PCX (Power Chamber Exhaust) Technology
• Chambered High-Flow Catalyst Cartridge Designed to Increase Torque
• Full Coverage Heat Shields
• Available in Chrome or Matte Black

Note: The selected finish/color refers to the full-coverage heat shields. The underlying header pipe finish/color may vary. Once installed, the selected color will be the primary visible finish.