Rinehart 4 1/2″ HP45 Slip-On Mufflers For Harley Touring 2017-2026

Rinehart HP45: Precision Engineering for the Performance Bagger Era

The Rinehart 4 1/2″ HP45 Slip-On Mufflers represent a bold new chapter for 2017-2026 Harley-Davidson Touring owners. Designed to complement the high-performance “ST” and Anniversary factory trim levels, the HP45 is more than just a sound upgrade; it is a specialized performance component for the Milwaukee-Eight 107, 114, 117, and 121 engines. By utilizing a massive 4.5-inch muffler body, Rinehart has created a larger internal volume that allows the exhaust gases to expand and resonate, producing a deeper, more forceful “thump” that standard 4-inch mufflers simply cannot replicate. Whether you are cruising on a Road Glide ST or a Street Glide Special, these mufflers provide the visual and auditory presence required for a modern performance bagger.

Unleashing the Power of the DBX Baffle

At the core of the HP45 is Rinehart’s acclaimed DBX performance baffle. This baffle is specifically engineered to “wake up” the Milwaukee-Eight engine, which is notoriously quiet from the factory. Unlike generic “loud” pipes that can sound hollow or raspy, the DBX core uses high-velocity internal geometry to enhance the low-frequency sound waves. This creates a crisp, mechanical bark under acceleration and a smooth, rhythmic rumble at idle. The engineering ensures that while you gain a significant increase in volume, the system maintains the perfect amount of backpressure to unlock hidden horsepower and torque. This makes the HP45 an ideal foundation for Stage I or Stage II builds where exhaust flow is critical to performance gains.

Expert Tuning & Installation Advice

As experts in the M8 Touring platform, we know that exhaust temperature management is vital. Pro Tip: The HP45 flows significantly more air than the stock mufflers. To prevent your engine from running too lean and to ensure your new bronze or chrome finish stays perfect, we highly recommend using a Vance & Hines Fuelpak FP4 or Dynojet Power Vision. A proper tune will richen the air-fuel mixture, cooling the engine and deepening the exhaust note. Installation Note: For 2021-later models, be aware that you may need new exhaust gaskets (OEM #65900017 & #65900056) if your originals are flattened or damaged during removal. To maintain the premium PVD finish on your end caps, avoid using harsh chemicals; a simple wipe with a microfiber cloth and a mild detailer is all that is required after the pipes have cooled.

The Distinctive Sound of American V-Twin Power

Every set of Rinehart HP45 mufflers is 100% Made in the USA, carrying the quality and craftsmanship that has made Rinehart a household name in the pits of NASCAR and IndyCar. The “Midnight Edition” and bronze-accented models offer a unique look that sets your bike apart from the standard chrome crowd. If you are looking for an exhaust that provides a “big-block” sound, race-caliber performance, and a style that matches your ST’s factory paint perfectly, the Rinehart HP45 is the definitive choice. It is the loudest, deepest, and most stylish slip-on in the Rinehart catalog.

Fitment Note: Fits all 2017-2026 Touring models. Not compatible with Trike models. Designed for use with OEM headers; will not fit with Rinehart Slimline Duals without specific adapters.

Rinehart 4 1/2″ HP45 Slip-On Mufflers For Harley Touring

A striking, bold addition to the Rinehart Racing catalog of performance products, the HP45 brings a fresh style and finish paired with race-inspired performance and power you’ve come to expect from Rinehart. Mufflers provide free-flowing exhaust while maintaining the perfect amount of back pressure, unlocking both horsepower and torque. Contrasting end caps are color-matched to pair perfectly with paints used by Harley Davidson on ST and Anniversary Touring models.

Features:

• 4.5″ muffler body diameter
• Works with factory head pipes
• Constructed with Rinehart DBX performance baffles
• Race caliber performance and awesome sound
• Chrome/Black and Chrome/Bourbon models feature PVD finished end caps
• End caps accents are color-matched to OEM HD paint used on FLTRXST Road Glide ST and Anniversary models
• Midnight Edition is a perfect match to your ST Touring bike
• Iconic Rinehart rumble included
• Sold as a pair