Crossover Pipe

[Grayrider]

99' fatboy.
Why do they have a crossover pipe on the exhaust? What does it do?
I think it is for balance but when running my pipes sound like they are individual.
Can these pipes be tuned or synchronized with the crossover or can I remove it?
If I remove the crossover, what is the difference between that and true duals?

[Hossamania]

The crossover is to balance the exhaust. The pipes are uneven length, and the crossover helps minimize that difference. In a perfect world, those pipe lengths would be equal. True duals try to make those headpipe lengths equal, but depending on the style, it can be tough, the rear pipe often has some extra bends in it to equal them up. Drag pipes and pipes of that style can be made equal length, but they do not end at the same spot, much like your stock pipes are, with the staggered mufflers.
You can cut that crossover out and tune for it, but if you're looking for power and efficiency, a properly built exhaust system is the better route, but they cost money, the one you have is paid for.
Your pipe can kind of be tuned by changing the baffles in the mufflers and leaving the crossover, but changing the baffles in your mufflers is not easy.
Some aftermarket pipes are better than others for performance, some are absolutely horrible.
It all depends on what you are going after.
One of the most common mods done to your pipes is to use a hole saw to cut out the discs in baffles in the mufflers. A minor mod, makes them sound louder, not too terribly loud, and tune the carb a little to make it run better.
For the record, most performance exhausts have some type of crossover or balance tube, or 2 into 1 design.

[tmwmoose]

Back in the evo days the motor gurues claimed the factory head pipes with a a good muffler such as Cycle shacks were a hard combo to beat power wise. I found that true myself on my ole 150 dyno . I oftain told the customer it was so the cylinder could share two mufflers for sound emissions and thats a true story that I made up One thing I found with a evo motor that ran the fatboy oem exhaust that had a weird dirty running rear head was the balance tube stuck out into the rear pipe a good 3/4" I think it was causing some type of obstruction /reversion I cut it down wasn't easy, bike never came back so who knows

[Grayrider]

I have SE pipes on it. When warmed and I throttle, it doesn't sound like the Rhineharts that were on my EG.
They don't sound together but like individual mufflers.
I have had the baffles out. I will try some things with them.
Thanks

[Coff 06]

Usually on the short Harley exhaust,the crossover tube is a good thing.It helps with scavenging out exhaust gasses between cylinders because they fire too close to the same time,(V-twin), and the exhaust can become lazy in the pipes.  JMO          Coff 06

[JW113]

The stock exhaust system is pretty restrictive, as anyone has altered it (what? who would do that? for shame!). The crossover let's both cylinders "share" both mufflers. Can you imagine how even more restrictive it would be with no crossover? They say that using slip on mufflers with the stock header pipes and crossover tube is supposed to be ideal, but I think many of the exhaust system vendors back in the day would not agree with that. Maybe they were just trying to upsell product, but I can tell you my evo did better with a pair of Python dual shorties than it did with slip ons. Not a lot, a couple HP, but just sayin'...

-JW