Questions about running straight exhaust (no baffling)

[psycledelic]

I had the cans off my 900 over the winter.  After doing some work I fired it up sans cans.  Sounded a bit old school muscle car at idle... never revved it in that condition.

length of pipes effects exhaust gas pressures.  Inequity in pressure from one cylinder to the other will change the power dynamics of the engine. have a look at this link
http://www.burnsstainless.com/TechArticles/Theory/theory.html
They do a way better job explaining that I could.

So from reading the burnsstainless page and taking what you are saying, the problems is not just that the pipe is short, but that it is short and open.  Short baffled, or at least choked down inside diameter of the pipe will build the backpressure that is needed. 

[ProTeal55]

It's all about the tune in the bike.
My s2r1k has a set of BoomTubes on it (pretty much as short as you can get exhaust wise) and the thing runs like a champ with a FATDUC O2 tricker deal-e-o on the bike. Only issue I am currently having is some exhaut leaks from the slip joints but that will be taken care of this weekend.

[psycledelic]

Well, I broke down and took it out yesterday (just couldn't resist).  All I can say is Son of a pregnant dog does that thing roar.  I would hate to see what the bigger engines can do.  I didn't have too much if any power loss nor did I have any stalling or popping.  Fumes were pretty bad, but I expected that with the exhaust stopping directly under me.  Still, I don't want to tear anything up (ear drums included), so cans are back on.  Now I am sure that I want a custom exhaust setup.  I really like the minimalist look and the exposed rear tire. 

[Mash]

I had my entire exhaust off yesterday for some maintenance.  When I got the header reinstalled, I cranked it up just to see what it sounds like without s-pipes or mufflers.  Wow, it sounded great.  As loud as a Harley, but a different character from the 'L' versus the 'V' configuration, I guess.  It was fun for a few minutes, then I reinstalled the rest of the pipes.

I use copper permatex on the slip joints.  It keeps the joints nice and tight, and stops the minimal blowby I was getting. Without it, the pipes were always a little loose.  I can tell when it's leaking because I can hear the pfft-pfft-pfft sound when it's running.

[psycledelic]

Where does one aquire a tube of that copper permatex?  what is it?  I am gonna have to find some.

[Slide Panda]

Where does one aquire a tube of that copper permatex?  what is it?  I am gonna have to find some.

]
Any decent auto parts shop should have it.  If you don't have one handy autobarn.com carries just about everything

[psycledelic]

Yea, I went out and found some.  Bike is back in tip top shape.  I appreciate everyones help and comments.  Thx.