Description

650Z-31T D&D Billet Cat Exhaust 2-into-1 Black for 2017-Newer M8 Harley FLH/FLT Touring Models

This D&D Billet Cat Exhaust will get you some sound from your M8 motorcycle. Check out this sound clip we did after installing it on our 2017 Road Glide Special:

D&D 650Z-31T Billet Cat 2-Into-1 Exhaust – Black

Fits 2017–Newer Harley-Davidson® FLH/FLT Touring Models

⚠️ Will NOT fit 2023 CVO Road Glide® or Street Glide® 121″ models with VVT

Stealth Black Performance for Milwaukee-Eight Touring Models

The D&D 650Z-31T Billet Cat is a full black 2-into-1 exhaust system engineered for 2017-newer Harley-Davidson® FLH and FLT Touring motorcycles.

It features a stepped header design (1 3/4″ → 1 7/8″ → 2 1/8″) that flows into a 2 1/2″ collector at the muffler. As a result, this system increases low-end torque while delivering strong mid- and top-end horsepower gains.

Additionally, the black finish gives your Touring bike a clean, aggressive, performance-driven look.

If you want one of the best performing exhaust systems available for the Milwaukee-Eight platform, this is it.

Choose the Right Baffle for Your Engine Build

D&D gives you two baffle options so you can match performance to your setup.

🔹 Vortex Wrapped Baffle (2 1/2″ Core)

• Best for stock displacement engines up to 114″

• Produces deep tone with strong torque

• Ideal for riders who want performance with controlled sound

🔹 Big Bore Baffle (All-Metal 2 1/2″ Core)

• Designed for Stage 4 114″, 117″, and aftermarket 120″+ builds

• Produces significant mid- and high-range horsepower gains

• Extremely aggressive and loud

Because we focus on performance first, we recommend the Big Bore baffle for larger displacement engines with matching cam and proper tuning. However, if maximum volume is your goal, this option definitely delivers.

Built for Tuners and Performance Riders

The 650Z-31T Billet Cat includes both 18mm and 12mm O2 bungs. Therefore, it works seamlessly with wideband auto-tune systems such as:

• ThunderMax AutoTune

• Dynojet Auto Tune

Moreover, D&D includes heat shields, new exhaust gaskets, quality flanges, mounting hardware, and your selected baffle. You do not need to purchase additional installation components.

The 4″ muffler housing completes the aggressive blacked-out look while maintaining proper bag clearance.

Unlock Its Full Potential with a Cam Upgrade

Although this system performs well on stock engines, it truly comes alive after a cam upgrade. Once paired with the right cam and tune, the sound becomes deeper, stronger, and unmistakably Harley-Davidson®.

At Cycle Solutions, we offer proven cam chest upgrade packages built for real performance. In fact, we install cam upgrades from our show truck at major events, giving riders immediate results without the stress of guessing the right combination.

When you’re ready to wake up your Milwaukee-Eight, this exhaust is the foundation.

Additional Options

• Dummy pipes available for wrapped saddlebag applications (select in dropdown)

• Multiple tip styles available

• Stepped header performance design

• True 2-into-1 torque-building configuration