why does harley connect one muffler to another. On some after market exhaust for harleys they dont have this and are seperate pipes.

 

It adds strength to the entire exhaust setup for one thing and it keeps the mufflers from vibrating to the point where they are actually banging into each other or, worse, falling off. The last time I went to remove my slipons, I discovered that the clamp on the lower muffler was actually loose. Because the top one was tight and the mufflers themselves were connected, it kept the bottom one from falling off down the road.

 

It also helps equalize the exhaust. If you notice on some systems, the rear head pipe may be shorter than the front. The crossover helps both cylinders breath equally.

 

I hate to be that guy but stregth has almost nothing do with why they connet the pipes. If you look you will see a that the connetion is made with a smaller tube between the two major pipes. This little connection is a way to produce the desired back pressure. This connetion is a way to try and get the exhaust to preform better while still being with in the EPA regulations for exhaust and noise. The little connection balances backpressure differences between the two cyclinders.Their is also a scavenging affect that can take place in some exhaust systems when set up correctly but that is a more complicated issue and revolves more around 2-1 systems. Most good after market systems will havea connectionlikethe stock systemas well. As for other pipes that are not connected really it comes down to what you want looks or preformance, 2-1 or conncected systems are easier to tune and generally out perform system that are not connected. Snooper I am not anexhaust kingpin but i did work in a service department as I went through college to be an engineering so Ihave a better idea than mostif you have some exhaust questions send me a PM.

 

That's a good point. I assumed he was talking about being connected by the steel rod between the mufflers. I hadn't considered the crossover pipe.

 

On V&H pipes(not all V&H have it) they call it apower chamber, Cobra pipes call it a power port.
different names same thing.