So I had what seemed like pad knockback at the track this weekend. I was a bit surprised because I have the non-brembo floating calipers.

Seems like this was a big discussion a few years ago:

https://my350z.com/forum/autocross-r...ub-flex-6.html

but generally people didn't seem to have a problem with the non-brembos.

My setup is:
2006 Touring
Hankook RS3
New OEM hubs on the front, I didn't swap the back bearings out.
Carbotech XP10/8 pads
Brake ducts.

The problem happened on a long sweeper into a braking zone. I actually went with the RS3 rather than R comps to save wear on the bearings. The video doesn't show the problem, I just did a double tap, but gives you an idea of the cornering loads:

http://www.vimeo.com/13079180

Guess I'll be left foot tapping in the future.

Just wondering if this is still standard operating procedure on a Z or someone has engineered a solution? I may do springs if I upgrade to Stoptech later.

 

Can't really tell anything by the video. You need to adjust the iris settings to get more information outside the vehicle...and, lose the music so we can hear what your are talking about.

Looks like your pads might not be getting up to temperature.

 

Ah... i remember your last video... Glad to see you got it up and running so quick.

Im in to find out about this too.

 

I haven't noticed any knock-back with my '05 non-Brembo calipers.

That's kind of my thoughts as well... Depending on the compound, race pads that are under temperature can have similar symptoms to pad knock-back. It would happen after you haven't touched the brakes for a bit, especially if that involved turns, and you'd get weaker initial bite and braking. My Hawk DTC-60's are noticeably softer when below operating temperature, but once I warm them up on my out-lap, they're pretty solid. No brake ducts on my car, so they get hot and stay hot, but no issues with them overheating either.

 

Bumping an old thread as I think I also have this issue.

After reading some other threads on pad knockback there is a general theme that floating calipers are better for this - but I seem to have some consistent pad knockback that seems to gets worse as the pads wear.

Some posts seemed to suggest that knockback was a non-issue with floating calipers but perhaps the truth is that it still exists?

 

And because everything is better with videos:

A lap (left foot tapping):
https://www.youtube.com/watch?v=LDgj...ature=youtu.be

The lap after. Pads almost used up. Tapping wasn't enough to firm the pedal up, I put the brake to the floor twice before getting braking force going into the chute (entering the boot). For some reason the knockback for me is always the worst on this course going into this turn - likely because of the sequence of turns before it. And then the pedal is normal ish for the turn immediately after.

https://www.youtube.com/watch?v=QOGx...ature=youtu.be

 

just tap the brake with your left foot to settle the pads back into place

 

I have experienced this as well as the pads get low.

 

Since the hub flexes regardless of caliper type, and because the action on the pads is more of a prying motion (the relative motion of the rotor is not linear), and probably also because the floating action on the caliper is never perfectly smooth (and maybe binding some due to the angle of the force)...the pistons are displaced same as with a fixed caliper resulting in knockback.

Are you talking about turn 6? Ive never raced the Glen, however you are using the inner loop and that would be a place after which I would expect knockback, especially since you arent really braking from the entry to inner loop until turn 6 (coming into the chute).