One thing to check is the gap each side now. The bars generally have a bit of 'give', and so will move a little. This can cause them to get close enough to panels to rub. I saw a bunch on Enduros that had rubbed. So much so that they redesigned the bars to give more room to panels.
I recently changed-over from the red Hepco-Becker engine guards to the black Wunderlich engine guards for a more-stealthy appearence:
I'm not a fan of bars, but would certainly consider those, for extra peace of mind, as they are very discreet