2012 Yamaha R6 I noticed there are a few of the front rotor buttons ever so slightly coming in contact with the brake pads on both front rotors. To be clear, they are not contacting the braking surface. They are just barely scrubbing the inner edge of the pad material. The issue cannot be felt while riding or pushing the bike around. It was seen as I was doing post-track time inspections and now I'm wondering if this is a good time for caliper spacers or if I should be looking into something else. Nothing appears to be out of place otherwise.
I had that issue when switching to Galfer wave rotors on my S1000, I measured the distance needed to get the pads completely onto the whole rotor surface and bought some spacers in that measurement. No more rubbing the buttons and the wheel spins freely and brakes are excellent.
OEM rotors Pad mfg is unknown at this time as I have yet to disassemble for further inspection. Will update this detail next time I'm working on the bike. There's no detectable rotor float on either side. What would otherwise cause the buttons to wear out?
Ahhh! I forgot the Yamaha has the dowel type insert. I even looked the fiche and thought it was a spacer.
Heavy use, particularly, if the wave washer has been removed from the button. (Assuming the OEMs are semi-floating - with the wave washer). As a side, if the rotors seem locked in place on the carriers, you might want to hit those buttons with some aggressive cleaning, like, maybe a pressure washer. You're not gonna hurt it, just don't blast the caliper pistons or axle/spacers. I'd remove the rotors for easier cleaning, lay 'em on a car's rubber floor mat or something and hold it there so it doesn't go skipping across the driveway.
