I think the HRC or Yoshimura systems only hit the swing arm if you use the standard rear set up(linkage/ride height), I have used a standard rear arm with the Ohlins superbike shock/linkage and HRC exhaust and it cleared the swing arm by quite a lot, but I was also running ALOT of rear ride height. I am now running a +20mm HRC swing arm, HRC shock/linkage set up with the HRC exhaust and again it clears by heaps.