03-04 pro circuit exhaust flange?

Any info on these. The only thing I see is that the 03-04 stock flanges have casting flaws and may break? Is there any performance to be had from these pro circuits?

No performance gains just a stronger design vs. the stock oem unit.

Thanks. Is it something I should consider changing? I imagine if the stocker broke while the motor was running it could cause some serious damage. How often do these things break?

I don't think it could cause seriuos engine damage but you'll have an exhaust leak. I've seen people post of them breaking but don't think it's common. If your going to change it I'd recomend the Boyesen unit it's stronger as well & offers slight gains off the bottom vs. the oem.

I can't imagine the stock flange breaking on it's own, it's a pretty hearty peice of steel. I did break mine from smashing the pipe into a stump, but mind you the impact was hard enough to wrap an FMF Gnarly around the frame.

I considered replacing it with the Boyeson unit as some people swore it made a difference. After looking over the OEM flange I have a hard believing there could be much difference, especially given the price difference.

I shut my bike down right after I realized the pipe was no longer connected to the cylinder, and no damage resulted, other than the flange and pipe being destroyed.

When i pulled my pipe off mine was cracked in 2 places.(I bought the bike used)

I bought a Pro Circuit flange and it seems like its alot stronger(thicker) then the OEM unit.For about the same price as OEM I'd get the Pro Circuit one and be done with it.

If it matters,I have not had any leaking where the pipe joins the flange so right off the bat I know it seals better.

BTW,good luck trying to find a Boyseen one,I dont think they make them asnymore.

BTW,good luck trying to find a Boyseen one,I dont think they make them asnymore.

I ordered one directly from Boyesen last year, not sure if they still sell them.

Whew $85! I guess I'll stick with my stocker until it breaks. Thanks for the info though.

Boyesen still sells them, I just bought one about a month ago. http://boyesen.com/exhaust-flange-1.html

Sorry my bad,I had read somewhere(maybe here) they were not available anymore :thumbsup: Non the less seems a little pricey for a flange that most likely wont do much.

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