Vance & Hines Big Radius: The Defining Exhaust for the Classic Dyna

The Vance & Hines Big Radius for 1991-2005 Harley-Davidson Dyna models is more than just an exhaust system; it is a visual masterpiece that has defined the “custom” look for decades. Compatible with the Super Glide, Low Rider, Wide Glide, and Convertible, these pipes replace the traditional straight-cut exhaust with a set of radical, sweeping curves. This era of Dyna—spanning both the final years of the 80″ Evolution engine and the introduction of the 88″ Twin Cam—is known for its raw, mechanical soul. The Big Radius highlights this character by exposing more of the engine and the signature Dyna frame, providing an aggressive “hot-rod” silhouette that makes your bike stand out in any crowd.

Precision Engineering and Superior Finish

While the Big Radius is famous for its style, it is built on a foundation of performance engineering. The pipes feature a stepped header design that optimizes exhaust gas velocity, ensuring that you don’t lose the low-end torque these classic V-Twins are famous for. The system includes 220-degree full-coverage heat shields that are plasma-arc cut for a precision fit. This “blue-proof” technology is essential for maintaining the brilliant, show-quality Chrome finish. Because the shields wrap nearly entirely around the head pipes and muffler bodies, they act as a robust thermal barrier, keeping the exterior surface looking showroom-fresh even after years of hard riding and high-temperature heat cycles.

Expert Tuning & Installation Advice

As specialists in the 1991-2005 Dyna era, we know these bikes require a specific approach to tuning. Pro Tip: Most 1991-2005 Dynas are carbureted (though some 2004-2005 models feature early EFI). If your bike has a carburetor, you must re-jet it when installing the Big Radius to prevent a lean condition. We recommend a Stage I jet kit to richen the mixture, which will eliminate deceleration popping and keep your engine running cooler. Installation Note: On these older Dynas, the mid-control brake linkage can sometimes be close to the front pipe; ensure your heat shield clamps are clocked correctly to avoid interference. Always use new exhaust gaskets (tapered style is best for this year range) to ensure a perfect seal at the cylinder head.

The Legendary Vance & Hines Sound

The sound of the Big Radius is unmistakable. At idle, it delivers a deep, percussive “thump” that perfectly captures the heart of a classic Harley V-Twin. Under load, it opens up into a crisp, authoritative bark that is louder than stock but remains refined and “melodic” compared to cheap straight pipes. It offers improved ground clearance for riders who enjoy the Dyna’s nimble handling in the twisties. For the rider who wants a high-quality, American-made exhaust that delivers both a show-winning look and a legendary soundtrack, the Vance & Hines Big Radius is the definitive choice for the 1991-2005 Dyna.

Fitment Note: Fits 1991-2005 Dyna models. 1991-2003 models may require a specific mounting bracket if using certain aftermarket forward controls. Not compatible with FLD Switchback models.

Vance & Hines Big Radius Exhaust For Harley Dyna

Turn heads with the classic curved look and aggressive hot rod sound of the Vance & Hines Big Radius Exhaust. These 2-1/2″ diameter pipes, crafted using 16-gauge steel, offer full-coverage heat shields and removable baffles. They feature a 2-into-2, downward-curved design with scalloped end tips, boosting the style of your Harley-Davidson Dyna motorcycle along with the torque and horsepower gains you’ll get over stock pipes.

Features:

• Custom bike styling
• Full-coverage heat shields
• Ported for oxygen sensors
• Louvered core baffles and mounting hardware included
• Optional quiet baffle sold separately 904-118
• Made in the USA