I was wondering if anyone has or has seen a stock R1 exhaust on a GS, I have a buddy that just replaced his with carbon fiber, and will give me his stock. I was wondering how it would act and sound, I know it would flow better than my stock, but the header still restricts flow, but a 1000 Im wondering if the muffle side will flow too much and give off a nasty sound, or undesirable. ANy thoughts or experiences are appreciated, yes I know filter and rejet.... I already have buddhas jet on the way... and waiting patiently.....

I think that stock R1 can is huge. I saw it mounted on GS (here on the forum) and I remember many people saying that it looks too large for little GS 
but you should do whatever YOU like, not what others will or will not 
the sound will stay almost the same (I had GSXR pipe installed on my bike and the sound was literally the same [sewing machine  ], little bit better air flow tho)

cheers
Kamil

the R1's pipe is like 1.5X bigger than the GS, so you will need to fabricate some sort of spacer or reducer to make it fit properly.   I ran a MIG highmount for an R1 on an EX500 once, had to fab up a reducer to make it fit my header, but you CAN do it.  dont let anyone say it wont work, cause it WILL.

Oh I know it can work, I can do just about anything automotive given enough time. trust me on that one. Im only inquiring about the sound and flow.

it will sound like a muffler and was designed for 2+ times the flow

it will be fine

Yeah... I bought one on ebay to put on my GS...its HUGE so i think im going to sell it to a pawn shop. the inlit diameter is pretty big to. its just too much.

thanx weston. I think I might do the same. find something different. I wonder how much flow would be increased by cutting off the collector and re working it into a larger diameter and cleaner joint on the inside. But keep the same runners. Ill have to think about this one, maybe find a stocker for cheap to play with. Anyone wanna get rid of a stock 04+ exhaust cheap. It will be hacked up and experimented on, then posted on here.