Does anyone know the replacement spec for the SR3 brake discs? I just replaced a brake disc due to damage (not wear) and measured it at 25.6mm. The brand new one measures 26mm. Wondering what the actual threshold is and whether I can get away with running just one new brake disc rather than replacing both, as is typically recommended.
Hi Victor (azwcat) on many of the rotors the minimum spec is stamped on the edge of the rotor. If you can’t find it let me know and I will dig through my notes to get it for you.
Charley
Hi Charley, the only stamping I see is the part number.
Hi Victor(@azwcat), sorry for the delay... I found in my notes that the new Floating Rotor thickness is 26.25mm and the thickness for the standard rotors is 24.25mm. The standard rotors are stamped with a minimum thickness of 22.8mm which means that they allow 1.45mm of wear. I was told by SM that they considered the minimum thickness of the floating rotors to be ~24mm which means they allow ~2.25mm of wear. So I would say that somewhere between 1.45mm and 2.25mm of wear is acceptable.
Charley
@charleyhradicalsportscarregistry-com, thanks!
Still a lot of life left in my other rotor. The difference between my R and L discs is .5mm. Any opinion on whether this is ok? I'm inclined to just go with it.
@azwcat - In my opinion 0.5mm difference will make zero difference in L/R brake balance. The distance the brake pads 'knock-off' the rotor face on both rotors should be the same, so there should be no issue there either.
I'd be more concerned if there was a difference in the surface finish (roughness) of the rotor faces between L/R rotors.
...try it and see
@rjbender, yeah I need to be careful on the scrub in laps. New rotor needs to be bedded in with the pads.
