I noticed how close the silencer was to the swing arm when I test fitted my system, it can be moved far enough away 8-10 mm if you slacken off the headers and where the mid pipe fits to the frame at the rear of the engine use 3 x spacer washers between the mount on the mid pipe and the engine, lightly tighten this up and mount the silencer before you secure the headers at the cylinder head, you'll notice you now have more clearance.
4 wheels move the body, but 2 wheels move the soul.
1982 Honda CB750 BOL D'OR
2017 Kawasaki GTR 1400
2017 Suzuki GSX S1000