So, I'm just thinking outloud here some and curious about what others think...but, I have an 09 FXDF with VH big radius 2-2 and a 15 FXDB w/ stock headers and SE slip ons. I recently removed the packing from the SE slip ons and drilled 2 3/8 holes in the baffles to open it up some. Sounds better now.

But I got to thinking - I know true duals sacrifice some performance for sound and look, but they can be real pricey. The FXDB has a crossover pipe that could easily be removed or plugged, making the stock header a true dual. Now assuming that the true dual setups are designed to balance backpressure on both cylinders and maybe the stock header with the crossover plugged might not, it should be close I would think.

Why don't more people take this route instead of dropping $500+ on a full system. Maybe in the case of my FXDF, you can't easily plug the crossover because its all one chamber. I'm thinking if I ever get the urge for that true dual sound, I may plug that crossover pipe... I can't imagine though an aftermarket header system would flow that much differently than the stock one (assuming you're comparing no cat in both and same muffler setup on both).

Also, I see enough people modifying the stock mufflers with different baffles or TTI's - Is there a downfall to doing this? I almost wish I would have saved my $400 I spent on the SE slip on's and just modified the stockers, because to be honest, I don't notice a huge difference in sound or performance between the two.

Thoughts? That was quite a ramble...

 

The crossover helps with scavenging. On a car, they call it an "H" pipe. It was the precursor to the now-preferred (for performance) "X" pipe. H pipe sounds better, though.

Most people in the know consider the newer SE slip-ons a waste of money.

Your variations mentioned above might affect power by ±2 horsepower. Unless you're really just chasing a dyno number, I wouldn't worry about it. Most won't notice the difference in power on the road.

 

But, in the end, a slip on is a slip on (assuming they are the same size) right?

I'd have a hard time believing a stock muffler with the same baffle as a SE muffler sounding that much different.

And, I did not realize the new SE pipes were so bottled up. The wife had a 1200 sporty with SE slip on's and it sounded pretty darn nice.

 

I bet you'll find that plugging the crossover pipe will hurt low end torque. Probably won't notice as much at high RPM.

 

Not really. There are several significant variations from an empty tube to a crimped and louvered baffle with fiber wrapping. And at least six steps in between.

Each will affect sound and power in different ways. I'm of the opinion that sound and style are more important than power, but others could give a damn about either and just want every last pony. That's a where a carefully tuned 2-into-1 comes in. The stock H pipe setup is actually quite good if you drop in some free-flowing baffles or properly sized lollipops (or DK Customs TTIs)

 

I just bored out the cat from the stock Fat Bob head pipe. I'll be running Rush 2in. slip-ons. Planning on adding Andrews 48 cams.
Not sure how the bike will run with the gutted out cat ?

 

I decatted the stockers and installed the TTI's. IIRC, the DK guy said that they would be just as good as the aftermarket exhausts. I was asking at the time what would be the difference after going this route from all the other $700-$1000 exhaust. I've started wearing earplugs since doing this (the pipes are loud as crap!), and the bike had to figure out what was going on in the ECM part. I went for a ride the other day and noticed that the bike ran much smoother, and overall better than before.

I'm still looking at 2-1's though, so go figure.

 

Personally, I'd take the money intended for nice pipes and put it toward a good tuner and maybe some dyno time. You'll see more benefits from a good tune than from pipes alone...and the tuner will be required if the mods continue to pile up.

 

CG is onit. I've ran lollipops on a couple of bikes that ran very well, if they're put in right. The 07 WG I've got now is running lollipops at the front of the muffler can (where they should be) and eight inches of two inch perf pipe in front of the end cap. Sounds awesome. The lollipops make a smoke ring in the muffler with the high frequencies on the outside of the ring. The perf pipe buffs out whatever comes down the outside of the can. This leaves the lower frequencies to come out untouched. My cans are on the end of a decatted 2012 WG pipe.

 

Bhaxton - your setup has gotten my interest. Could you snap a few pics?