I had the 30mm. American Machine barbacks from Pirate on my '04KRS. I liked them. Barbacks are very subjective. I'm 5'8" W/30" inseam.
The 30mm. barbacks took the weight off my wrists and made for a very good ride.
You don't have to replace or relocate any lines or cables on a '04KRS with the 30mm. barbacks. Simply cutting any ty-raps on the switch wiring made things right. Although at full right lock the brake hose is at max. length!!
'04 K1200RS Capri Blue(totaled)
2008 Triumph Sprint ST