I wouldn't say they are the last word in motorcycle exhausts. Arata is right there with Akra.

What do you mean by a "true dual?"

True dual:

http://www.southerncarparts.com/imag...vo-Exhaust.jpg


not true dual:

http://i.ebayimg.com/t/Nissan-370Z-Z...w9!~~60_35.JPG



true dual is 2 pipes from the headers back. and does not collect into 1 pipe anywhere except where the X or H pipe is

Cool. Where in the first pic is the x and the h pipe? How can a CBE be dual or single? Don't only the TP's determine that. Is the stock dual? This is the Remus CBEhttp://img.tapatalk.com/4d7d5770-4bb1-dcb5.jpg

No thats the akrapovice cat back. so basically all test pipes are is about a 1 foot length of pipe that connect the headers to the cat back. they take the place of the stock cat. after that is the "Y pipe" which is shapped just like the name implies. now some exhaust systems connect to the stock y pipe and some replace it. in the case of that akrapovic, it replaces it. whereas the topspeed catback pictured bellow it bolts onto the factory y pipe.

in the picture of the akro system u can see the "H" pipe connecting the 2 sides of the exhaust between the flex pipes and the resonater. this evens out the exhaust pressures in both sides of the exhaust.

here is an "H" pipe and an "X" pipe beside each other:

http://powertrix.com/agoracart55/htm.../EX_H_Pipe.jpg


as the name implies, one is shape like an "H" and one is shaped like an "X". there is really no advantage to one over the other. they are just different ways to do the same job.
basically if you get test pipes, any system that is a "true dual" will bolt up to it.

What are these second two pics called? I thought the difference between the two types of akropovic (evolution and slip-on) was one had tp's and the other didn't. These basically connect to the stock h-pipe? Is the the stock exhaust system truly dual? This is my friends hks setup.http://img.tapatalk.com/4d7d5770-5f5b-a63d.jpg

The second two pics in that post are just the rear muffler/silencer, the very back of the exhaust.

The picture of my friends exhaust setup separates into two mufflers while these are one muffler. Can this still be called a dual system

yes. even the ones that come into one muffler are still considered true duals. the flow chambers are actually still seperate inside the muffler case. imagine it like the one pictured below, with a big case around it.


http://i.ebayimg.com/06/!B6,tbsQCGk~...PNEGZ!~~_3.JPG


i just did a little looking and the difference between akrapovics slip on system and the evolution system is that you will only get the muffler in the slip on, just as u implied above. it will bolt in place of your existing muffler and uses existing mounting points.

the evolution system is from the catalytic converters back. (cat back)

i can't imagine just the slip on changing sound (or performance) that dramatically since u will be using all stock other than the muffler

no systems will come with test pipes from my knowledge. thats something that will have to be purchased seperately.

Yep, back in Europe, Remus , Supersprint, Scorpion Exhaust systems top quality and sound.