Exhaust - build or buy?

Looking to upgrade the stock exhaust on my FZ6. Previously removed baffling from stock can but didn't really make much difference. Shopping around it looks like a slip on is 600-1000 which seems like a lot. I was thinking of building my own but wasn't sure if that would be detrimental to performance on a modern injected engine without the proper design. What says grm?

I had a Kerker 4 into 1 header with a Supertrapp on my GPz-1100, when the baffling wore out and there was less back pressure, performance sucked.

Smarter people than you and I designed the stock pipes.

What some folks do is get take-off mufflers from different bikes and have them welded to the factory system. I could see something like factory Termi's off of a Ducati displacing 900cc's or larger flowing really well, sounding decent, and being pretty cheap on ebay being a good path to take.

To build on what 914Driver suggested, you will probably want to be able to adjust the fuel side of the bike if you make a change like this. A PowerCommander or similar device would be smart, or at least an adjustable fuel pressure regulator to fatten things up a little. A lot of VFR800 owners would do one or both of these after simply gutting their stock cans; that bike runs pretty lean from the factory, and the change in exhaust flow would really cause running issues until they tweaked fuel curves.

I want to keep the stealth under-seat look of the factory exhaust so my plan was to look around for an aftermarket muffler that fits in the space and then plumb the in and outs up to the stock locations. If I used a proper aftermarket muffler would that meet the back pressure requirements or is there no way to know? How about a muffler designed for a car? The stock can is flat and wide like a car already. I plan on keeping the stock headers and cat sections.

Thanks!

In reply to Armitage:

An FZ6 enthusiast's forum would probably be the best place to ask.

If I was doing this on my VFR, yes, I'd need to address fueling. Your bike may be different in this regard. Hard to know without firsthand experience.

914Driver wrote: I had a Kerker 4 into 1 header with a Supertrapp on my GPz-1100, when the baffling wore out and there was less back pressure, performance sucked. Smarter people than you and I designed the stock pipes.

My 89 Honda hawk gt has a two brothers full system on it. The baffles are gone and I hadn't considered back pressure as a reason why performance seems a little lacking

Take that money and do a couple track days. If you have not done one or raced before, you might find the bike with the stock exhaust it faster then you.

Steve

Older bike? Go nuts with the custom exhaust. Modern bike? Exhaust is quite finicky. I'd let the experts figure it out.

Thanks for the input guys. I'm leaning towards buying instead of building at this point. Found this slip-on that hides behind the factory cowl thing for that OEM look.