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Discussion Starter #1 (Edited)
I made a playlist on YouTube to compare some different exhaust options on the bike.
They were all recorded on the same phone. Unfortunately, the stock exhaust was inside a garage, so its not a 100 perfect comparison.
https://www.youtube.com/playlist?list=PLuWIt-6C1Skjhp7UzOHNuQRntB3_kexTu

I have my old bike running with the stock exhaust (Heat shields are loose and rattle).
In that video, I pull off the mufflers while it's running to hear the difference

Then I have my new bike with the Vance & Hines pipes in full baffle configuration.

Then I have my new bike with the Vance & Hines pipes with one inner baffle removed.

Then I have my new bike with the Vance & Hines pipes with one running straight (No baffle/no fiberglass)

And finally, my preference, my new bike with the Vance & Hines pipes with both inner baffles removed.

My impressions, the stock exhaust is too quiet. I need to hear the engine at 60-70 mph.
Pulling the mufflers off behind the goats belly adds a BUNCH of low end rumble and some good punch.

The Vance and Hines with full baffles have a very nice crispness to them. Being true dual pipes, they have a lovely left-right-left-right interplay that the stock exhaust with GB couldn't match. However, I found it lacking a little low end for my tastes, and almost started to fade into the wind noise at 70 mph.

Removing the inner baffles kept the crispness while adding a bit of low end, without getting over-the-top loud.

Removing the outer baffles and fiberglass was obnoxious! Full *sshole status. :doh:
From where I was standing, it didn't sound quite as tubby as it does from behind.

I ran it briefly (not in videos) without the baffles, but with the fiberglass still packed inside. With nothing to hold it in place, this obviously wouldn't work. However, it was an interesting in-between sound between straight pipe and just the outer baffles. It added more low end and removed more high end. I'm not sure how to describe it other than it just sounded bigger. It was certainly louder, but nowhere near as obnoxious as straight pipes.

EDIT: With some more time on the partial baffle V&H pipes, I found a few more things I like about it.
I discovered that the slash cut of the V&H pipes directs a reasonable amount of sound out to the sides.
I can hear a volume increase when I lean into a corner (because of sound bouncing off the pavement).
I also hear concrete barriers/tall curbs, cars in my blind spot, and large buildings on the sides of the road.
Regardless of the exhaust type you use, directing sound to the sides has a very real spacial awareness benefits!

If you fall into the "loud pipes save lives" camp, do yourself a favor and direct the sound to the sides rather than behind you.
It's not people behind you that need to hear you.

The V&H with partial baffles fall into the "earplugs recommended" category. I do get a bit of ear fatigue on longer rides. I was used to riding GB without mufflers, and the overall volume was similar. I typically used earplugs for rides over 10 minutes with that setup.

Since my current bike came with these pipes, I cannot say what the jetting is. I have not yet opened the carbs. My first bike did NOT need a rejet when I removed the mufflers, provided the intake was stock. The combination of an earshave AND removing the mufflers needed a rejet to 40/140 with no shims. Putting the mufflers back on would cause a rich stumble at WOT.

EDIT: I ran the math for exhaust pipe tuning.
The equations all came from this site https://www.musclecardiy.com/performance/exhaust-system-performance-math/
I found the Exhaust Valve Opening number to be 66 degrees (manual camshaft specs).

The stock system has a tuning RPM based on each pipe total length, as well as for the Goats Belly or a crossover pipe.
Since the stock pipes are unequal length, that results in two RPM tunings.
Since the firing is not regularly spaced (305, 415 intervals), the crossover results in two tunings.

This puts the stock exhaust tuning at 2700, 3950, 5200 and 8300.
The V&H true dual pipes do not have a crossover, so they only have two tunings of 4900 and 7350.

The math suggests a loss of torque below 5000 and above 7500, with similar or improved performance between 5000-7500.
 

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Thank you for taking the time to post this. I've been racking my brain trying to figure which direction to go for pipes. So this is VERY helpful. Now is this set of Vance and hines made for the vn 750. If not what model are they? Again
 

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Discussion Starter #3

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Does anyone make a slip on? Is rejetting needed?
There is no slip-on made specifically for the VN750, but you can certainly fit something with a 1.75 in inlet if you’re keeping the goats belly in place. Some say Harley Sportster muffs work and others claim they fit but aren’t that good on this bike. So you have options
Regardless if you keep the stock air intake intact you should not need to rejet.
 

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Discussion Starter #6
The stock mufflers are 2.5" inlet, going up to 3".
1.75" must be to fit inside the output of the Goats Belly.

Something like this should fit nicely, if you cut the included bracket off.
It starts at 2.5" and goes up to 3" at just the right spot to use the stock heat shield bracket.
https://www.jegs.com/i/Gibson-Performance-Exhaust/462/500383/10002/-1
 

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The stock mufflers are 2.5" inlet, going up to 3".
1.75" must be to fit inside the output of the Goats Belly.

Something like this should fit nicely, if you cut the included bracket off.
It starts at 2.5" and goes up to 3" at just the right spot to use the stock heat shield bracket.
https://www.jegs.com/i/Gibson-Performance-Exhaust/462/500383/10002/-1

1.75 is the OUTSIDE diameter of the outlet pipes on the goats belly. The stock mufflers clamps fit these pipes with the graphite gaskets.
 

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FREEBIRDS MC CENTRAL NY
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Does anyone make a slip on? Is rejetting needed?
Harley screaming eagle mufflers should bolt on the goat's belly

Sent from my A501DL using Tapatalk
 

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