florindi

Hi All,

I replaced my rotors and pads for the my C2S. I glazed my stock pads at the track at the end of last year. I am trying the Carbotechs 1521 for the street this time. I have had good luck with this pad on my other cars. The pad does not create a lot of dust and has good bite. However, my pedal was real soft after installing the rotor and pads. I tried bedding the pads and while doing my 60-20 mph stops the pedal went almost to the floor. I then decided to bleed my brakes. I went through at least a 1/2 liter of fluid and saw only a few little bubbles from the front calipers. The pedal is still soft after bleeding. Is there air trapped in the ABS module or somewhere else? Anyone have any ideas?

Thanks,
Anthony

RonCT

Could this just be that the pad's friction coefficient is very low compared with stock? That could cause you to have to press the pedal more to get the same braking effect. I know some pads I use with a very high coefficient bite like crazy - so when I switch from stock to race for the track, I have to change my braking habits.

florindi

Ron,
You could be right about the pad friction coefficient. Though, these pads felt good on my Mazda speed 3. I need to try the bedding process again. Otherwise,
I will be looking for a different pad. Probably back to Pagid.

MUSSBERGER

Soft pedal doesn't sound like bedding to me. You got air some where. IMO

Sub

I am not sure how it happens, but almost every time I've changed pads (not on a 911- still looking for one, but on my z06), I almost always got a soft pedal. I still cant figure out why other than that maybe it has something to do with pushing the pistons back in.. Anyway, I ALWAYS bleed now after changing pads.

Just bleed your brakes. A little trick a track veteran taught me was to take a rubber mallet and while you bleed, tap around the caliper and lines to release bubbles and dirt. Its amazing what comes out when you tap around.

BTW, Carbotech are awesome pads. I've used them for years on my z06 at the track.

Sadiq

1/2 a liter doesn't sound like much.. also you're probably right about air in the ABS system. In some cars (not sure about 997), you can bleed this system by bleeding once, then driving and braking hard to engage teh ABS a few times, then bleed again. You may need to repeat. Shops also have ways of bleeding directly, though I believe it takes an expensive tool that a guy would never have in his garage.

Sub

Good point Sadiq. I had a car with soft pedal, couldnt fix it. I engaged abs one day on a panic stop and from then on the pedal was hard! I guess there was air in there from the factory.

florindi

Thanks for the tips!
I re-bled the brakes and it feels better, but not perfect yet. I'm going to try the rubber mallet trick and try to activate my ABS.

mglobe

Did you also bleed the clutch when you did the brake bleed? Air can hide there.

TrackDays247.com

+1 on the caliper tap, de rigeur when changing out.

Also, new pads & rotors at the same time normally is not the preferred way to go -
*Check your caliper dust boots as a TON of crud jams in there. A SOFT wet toothbrush helps here.*