What you need to know is "How much tire is still in contact with the road, after the pegs start to scrape?"
I had a 2000 VFR with which I had ground off the feeler (and part of the peg) on the right side. Then one day, in a right-hand corner, nothing scraping, I give it gas and lose the rear wind. I get slammed on my back and the bike slides down the track ahead of me.
Afterwards, looking at the rear tire, it is clear I leaned it further than there was tire to keep on the road. The VFR has pretty long feelers, and I think they designed it this way to let you know you're getting to the edge of the tire. So without feelers, I was leaning too far.
Granted, the FJR has lower pegs, and may have plenty of tread left when the next hard part starts dragging. I'm just pointing out that the limit to leaning may not be the parts you're dragging, but the rubber left to provide traction.