pipe questions

[what?!]

uber noob question...i guess...how are exhaust pipes, for example yoshimura, made specifically for different bikes?  and why?  i mean, i guess a can's a can, but can any exhaust with a certain inlet pipe be welded/fabricated to fit onto a different bike?  like a gs for instance?

i was on ebay a while ago and i saw a stock cbr f3 (?) pipe on sale as an "upgrade" to the gs.  so i figured if the exhaust has the same piping, they should work.  it's just say if i got the f3's yosh exhaust, the can's essentially designed for a 600cc 4-cyl bike...but is that really a problem?  especially if it's just a straight-through design?  i mean, there's that guy that put a wrx can on his bike haha.  even though i'm sure he had to rejet the $#!+ out of that bike...

just food for thought i guess...please don't bash  

ahem, davipu...

[davipu]

internal baffle designs, length, diameter of baffle/pipe lenght of header/midpipe all affect back pressure/exaust impulse's if it's tuned right the other pulses will pull the exaust out if the cyls. a badly tunned one will cause extra pressure and will cause the bike to run poorly.

dude I don't bash/flame/whatever you call it, most of the time.

[The Buddha]

OK the stock GS motor ... the main restrictions are in the ports, valves and the heads itself. So whatever the pipe you have ... big deal ... I have tried WFO D&D, and a smallish Kerker and an even smaller cobra F1-R ... remarkably same from riding point of view ... jetting too is awfully close, with the extra washer and air screw settings being all that were different ... so your pipe has very little to do with anyhting WRX can or not. If you start opening up ports etc ... then you may start getting to the limit of the pipes ... then I have no idea ... a 2 into 2 will be better for this motor, but then again it will hardly be noticeable with a stock motor ... heck the extra weight of the other can will hurt the performance more than anyhting the motor can gain ...
Cool.
Srinath.