I've heard that there are three reasons people change their exhaust: 1) Looks 2) Sound 3) Performance.

Looks and Sound are simply a personal choice and people each have their own opinion on what they like. However, when it comes to increasing Performance, I've googled around and found conflicting information. There seems to be one school of thought that removing baffles and restrictions on air flow out of the engine will increase performance. But there is another school of thought that says this is not true, and that things like straight pipes without baffles reduce performance. Can someone please shine some light on this topic? Anybody every run a dyno to see any change in HP between the different kinds? Thx

 

I'll give my mostly ill-informed, un-educated point of view.

I lump looks & sound together. So you either buy a pipe for the looks & sound or for performance.

If you want performance you buy some form of 2 into 1 exhaust like a D&D Fatcat and within the 2 into 1 family try to pick one with the sound you like best, perhaps using different baffles (some wrapped with material to produce a deeper "quieter" sound) depending on the desired sound.

If you want looks & sound you pick something else (this is not to say I think 2 into 1 pipes are ugly).

I for instance picked V&H BSS pipes for my bike based on 2 things:

1) I had heard of V&H
2) They looked badass on my bike (obviously subjective).

I'm not crazy about the sound and know (now) that I will suffer a performance penalty (low-mid torque will never match a 2 into 1).

If I had it to do over, I would have picked the D&D Fatcat in black because to me it looks OK and will produce proven performance.

As to running no baffles or taking a hammer and screwdriver to removing baffles, everything I have seen indicates this is a bad idea. It will definitely make it louder. So loud that no one will want to ride behind you and your neighbors will hate you. But everything I have read indicates that performance will suffer dramatically and the sound while loud is not pleasant to most ears.

I'm sure others will have a differing opinion, but that's how I see it.

 

Drag pipes or "open" pipes with little to no back pressure will help the top end performance but low to mid range will suffer significantly. Open pipes are for the drag strip or those whose desire is to be overly obnoxious.

 

If looks and/or sound is important to you, and performance is also...then it is going to come down to some sort of compromise...usually with your wallet. lol

You also need to determine what type of performance you want...top end HP or low and mid range torque...or a compromise between those two.

Learning about back pressure, flow, reversion can quickly become a in depth study.

ohh...and then there is how to get rid of decel popping if you don't like that...that usually also will involve some compromise...either in sound or lower MPG, and definitely the wallet.

Big subject.

Kevin

 

Let's hear it for the open pipes .... people hear em i stay alive lovely old job!

 

If you really want to know what it takes to makes a good high performance exhaust system give frank a call at Drago's bike works.

http://www.dragosbikeworks.com/

I called to ask a question about one of his exhausts. He spent over 30 minutes explaining exhaust design requirements to me! He told me all the whys, whats and hows that go into designing a high performance exhaust.

When he was done I decided he really knew what he was talking about and purchased one of his exhausts....

 

Me performance first then looks.

 

I went for performance 1st, then looks, and then sound. As a result, I purchased the Vance & Hines Pro Pipe HS about 8 years ago and think it is a great exhaust system.