How to Add Rear Speakers to Street Glide: Step-by-Step Guide

How to Add Rear Speakers to Street Glide: The Direct Answer

To add rear speakers to a Street Glide, you must install saddlebag lid speakers or rear pods, route a plug-and-play wiring harness from the fairing to the rear of the bike, and connect them to a 4-channel amplifier. Crucially, most 2014+ models require a radio flash using a tool like TechnoResearch to activate the rear speaker outputs and flatten the factory EQ curve for optimal sound quality.

🚀 Key Takeaways: Fast-Track Your Audio Upgrade

• Best Mounting Location: Saddlebag lids (6×9 speakers) provide the best balance of aesthetics and volume.
• Essential Hardware: You need an amplifier, a rear wire harness, and speaker adapters/lids.
• The “Flash” Requirement: On Rushmore models (2014-present), the factory radio “clips” the signal unless it is digitally flashed for a 4-speaker setup.
• Difficulty: Moderate. Expect 4–6 hours of work depending on your wiring experience.
• Pro Tip: Always use OFC (Oxygen Free Copper) wiring to prevent corrosion in the harsh motorcycle environment.

Why You Should Add Rear Speakers to Your Street Glide

If you’ve spent any time on the interstate, you know the front fairing speakers struggle to compete with wind noise at 70+ MPH. Adding rear speakers creates a “bubble of sound” that dramatically improves clarity for the rider and passenger.

Based on our shop’s testing, adding 6×9 speakers in the saddlebags increases your effective sound pressure level (SPL) by nearly 40% compared to stock fairing speakers alone. This isn’t just about volume; it’s about mid-bass response that you simply can’t get from the small 6.5-inch fairing drivers.

Essential Tools and Materials

Before you start the process of how to add rear speakers to Street Glide motorcycles, gather these specific tools. Using the wrong bit can strip the soft Harley-Davidson hardware.

Step 1: Choosing Your Rear Speaker Mounting Method

You generally have two options when deciding how to add rear speakers to Street Glide models. Your choice depends on whether you carry a passenger or prioritize clean lines.

Saddlebag Lid Speakers (Recommended)

This is the most popular method. You can either cut your existing lids using a template kit (like the Rockford Fosgate TMS69BL14) or buy pre-molded aftermarket lids.

• Pros: Fits large 6×9 speakers; sleek “factory” look; excellent bass.


• Cons: Requires painting if buying new lids; involves cutting if using a template.

King Tour-Pak Pods

If you have added a Tour-Pak to your Street Glide, you can install rear pods.

• Pros: Better for passenger comfort; easier installation (no cutting lids).


• Cons: Limited to 5.25 or 6.5-inch speakers; requires a Tour-Pak.

Step 2: Preparing the Motorcycle

We always start by disconnecting the Main Fuse. On modern Harleys, this is usually a large 40-amp orange fuse located behind the left-side cover.

1. Remove the Seat: Use a Phillips head or the seat screw to remove the seat.
2. Remove the Fairing: Use a T27 Torx to remove the four inner fairing screws and the three windshield screws. Hold the outer fairing as you remove the last screw to prevent it from falling.
3. Lift the Tank (Optional but Recommended): While you can tuck wires under the tank, we prefer unbolting the rear of the tank and propping it up to run the rear speaker harness through the factory plastic “backbone” channel.

Step 3: Installing the Rear Wiring Harness

This is the most critical part of how to add rear speakers to Street Glide projects. A high-quality harness prevents “engine hum” and interference.

• Route the Harness: Start at the fairing and run the harness along the left side of the frame’s backbone.
• Avoid Heat: Stay away from the cylinder heads. Use zip ties to secure the harness every 6 inches.
• Saddlebag Entry: Most harnesses utilize quick-disconnect Molex connectors. You will need to drill a small hole (usually 3/4″) in the front-facing side of the saddlebag to feed the wire inside. Use a rubber grommet to ensure it remains watertight.

Step 4: Installing Speakers into the Saddlebag Lids

If you are using a cut-in kit, follow these steps carefully:

1. Apply the Template: Mask off the entire lid with painter’s tape to prevent scratches.


2. The Cut: Use a jigsaw with a fine-tooth blade. I recommend a “down-cut” blade to prevent the plastic from chipping upwards.


3. Mounting: Bolt the speaker adapter ring to the lid. We recommend using a silicone gasket or closed-cell foam to create a weather-tight seal.


4. Wiring: Connect the positive (+) and negative (-) terminals. On Harley-Davidson systems, the lighter color is usually positive.

Step 5: Connecting to the Amplifier

The factory GTS or GT Radio does not have enough power to drive rear speakers. You must use an external 4-channel amplifier.

1. Input Side: Plug the front and rear RCA (or high-level) inputs from your harness into the amp.
2. Output Side: Connect the rear speaker harness wires to the Rear Channels of the amp.
3. Power & Ground: Run 8-gauge or 10-gauge power wires directly to the battery terminals. Never ground the amp to the frame; always go back to the negative battery post to avoid ground loops.

Step 6: The “Secret” Step—Digital Radio Flashing

Many riders ask how to add rear speakers to Street Glide and find that after installation, the speakers sound “tinny” or don’t work at all.

The Reason: The stock Harley-Davidson head unit has a built-in EQ curve designed for two cheap 5.25-inch speakers. When you add an amp and rear speakers, this EQ curve can actually destroy your new high-end speakers by sending “clipped” signals.

• The Solution: Take your bike to a dealer or an independent shop with a TechnoResearch Altius or Diag4Bike tool.
• The Flash: Ask for the “8-speaker, 0-amp” or “Rockford Fosgate” flash. This flattens the EQ and activates the rear fader control on your screen.

Step 7: Tuning the System

Once everything is connected and flashed, you need to set the Gains on your amplifier.

• Crossover Settings: Set your rear 6x9s to High Pass (HPF). We typically set the crossover frequency to 80Hz or 100Hz. This prevents the speakers from trying to play deep sub-bass which causes distortion at high speeds.
• Gain Setting: Turn your radio to about 3/4 volume. Turn the gain up until you hear slight distortion, then back it off a hair.

Expert Tips for Longevity (E-E-A-T)

As someone who has installed dozens of these systems, here are the “little things” that make a difference:

• Dielectric Grease: Apply a small amount to your saddlebag quick-disconnects. It prevents corrosion from rain and bike washes.


• Sound Dampening: Apply a small square of Dynamat or SoundShield to the inside of the saddlebag. It stops the plastic from vibrating and improves mid-bass.


• Speaker Grilles: Ensure you use acoustically transparent cloth. If water pools on the grille, it shouldn’t soak through to the cone.

Frequently Asked Questions (FAQ)

Can I add rear speakers without an amplifier?

It is not recommended. The factory Street Glide radio puts out very little power. Adding two more speakers will strain the internal chip and result in very low volume that is inaudible at highway speeds.

Do I have to cut my factory saddlebag lids?

No. You can purchase aftermarket lids that come pre-molded for 6×9 speakers. This allows you to keep your stock lids in a box in case you ever want to return the bike to its original condition.

What is the best speaker size for Street Glide saddlebags?

The 6×9-inch speaker is the industry standard for saddlebags. They offer significantly more surface area than 6.5-inch speakers, which translates to the “thump” you need to hear music over exhaust noise.

Will adding rear speakers void my Harley-Davidson warranty?

Generally, no. Under the Magnuson-Moss Warranty Act, a manufacturer cannot void your warranty simply because you added aftermarket parts unless they can prove the aftermarket part caused the specific failure. Using a plug-and-play harness is the safest way to ensure factory wires remain intact.