I’ve been recommended to change the pad at the same time as changing the disks, is this right? Why?
The disk haven’t been changed in 9,500 miles (half a dozen trackdays) and the Pagids have done about 2000 miles (and about 4 days).
Even with the newly upgraded braided lines and fluid (SRF) the pedal still went a little spongy after 15 mins. I’m assuming the worn disks don’t get rid of the heat as well as new ones. The Pagids still look like they’ve got quite a bit left.
Don’t do it.
In fact, you need to bed in the disks with bedded pads.
They probably mentioned that thinking of the originals, but you already have Pagids.
Just clean the pads and flatten the contact face with sandpaper, so that you put even pressure on the new disk and you should be ok.
there’s no reason to believe the disks just because they’re old, they won’t dissipate heat.
If anything they would work better since they are really compressed. Disk faults that would make the system perform worse are:
-warping
-cementite depositions (if juddering while hot)
-scoreing (had any metal to metal contact?)
-wear (thinner, less thermally stable, inducing probably juddering or warping)
If your pedal is going spongy is not the disks fault, there must be another reason (master cylinder, air in the system, etc)
Apart from bleeding the system again try getting one of those brake piston winders (I got mine at Burton’s). Sometimes when I use bad pads (EBC) it makes the pedal go soft after hard use. It doen’t go away with normal driving, but if I take them off, wind the pistons fully back using the tool and put them again, the pedal is really solid.
This may be because of air trapped somewhere and being pushed back into the reservoir, effectively “bleeding” itself.
I found the Pagids only last until they wear down to the brass rivits … still got quite some wear left but I was getting a spongy pedal as well. ( the rivits just become visible in the material ) - I thought I read somewhere that that was the time to change …