Replacing pads w/o machining the rotors

[timothy]

Some suggest to sandpaper the rotors when switching to a different pad compound.

[Lil bastard]

Originally Posted by timothy

Some suggest to sandpaper the rotors when switching to a different pad compound.

ABSOLUTELY!!!

If you 'mic' your rotors, and they're within spec (assuming there is no perceivable warparge), you do want to remove any traces of the old compound before adding new pads.

Brakes work 'best' when the pad lays down a layer of material on the rotor so you get material-to-material contact.

Sanding the rotors with 80-40 grit sandpaper removes the old compound, leaving a fresh surface to build-up a layer of the new pad material during the bed-in.

[Maxodus]

...awesome feedbacks, thanks guys. The idea of sandpaper sounds great, i'll definitely give it a try this weekend~

[eslai]

I would not bother scrubbing with sandpaper. If you properly bed the pads with a proper break-in procedure, they'll be fine.

Stoptech has some great articles online about brake theory, for instance, here's their take on proper bed-in procedure:

http://www.stoptech.com/tech_info/wp_bedinstock.shtml