Akrapovic Racing Line Full System Schematic.
Link pipe: Inlet, 52.5 mm O.D., Outlet 59.5mm
Muffler: 60 mm I.D.
These systems have been out of production since 2008.
Also, carbon mufflers don't last long on twins. The power pulses pulverize the carbon sleeves into mush after a while.
Mine lasted only two years before they got tons of cracks.
If you can find all the parts but the mufflers, I suggest contacting SimonKobeJapan on this forum to price a pair of LBP titanium large oval mufflers with 60mm I.D. inlets (unless you can locate a pair of the Akrapovic mufflers in titanium)
That's what I did. The LBP titanium mufflers are not only way more durable, but they weight much less than the Akrapovic carbon mufflers.