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Knockback Springs and Street Usage

Old Jun 17, 2008 | 05:57 PM
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Default Knockback Springs and Street Usage

Okay, pad knockback reared it's ugly head this last weekend at Miller Motorsports Park, especially after a series of S turns (known as the "Attitudes"...)

I've read the various StopTech articles on knockback, and I've read all the threads I could find her eon my350.

Who actually is running knockback springs, how much has it helped, and how pad of pad wear do you get if you are daily driving your Z/G?

Dave
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Old Jun 17, 2008 | 06:02 PM
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its funny to see all these problems with knock back because i have no problem out of my brembos and i drive the crap out of my on R comps. As for life on the street depends on how strong they are.
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Old Jun 17, 2008 | 06:26 PM
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I have the ST40 Stoptechs and brutalised them this weekend at Sebring and had no problem with pad knockback. I would inspect/replace the hub and bearing and not try and remedy the problem at the caliper.
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Old Jun 18, 2008 | 02:19 AM
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I have knock back and I replaced all my hubs this past winter. I've just learned to tap the brakes slightly before a brake zone. If your on brand new pads it's obviously not as bad.
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Old Jun 18, 2008 | 04:08 AM
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No knock back. I had 4 days at VIR (2 at Full, 2 at Grand) over the last month running Carbotech XP10 front and rear. No issues, just lovely lovely braking. OEM Brembos.
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Old Jun 18, 2008 | 04:13 AM
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I don't know if I have had "pad knock-back" but I have experience "NO PEDAL" on occasions. On a few occasions I would hit the brake and the pedal go WAY DOWN,,,then the problem wouldn't happen again the entire weekend. But this was NOT brake fade, just NO PEDAL

This problem caused me to go off @ Barber a couple a weeks ago while running a NASA TT event...Scared the crap out of me. So I have learned to "left foot tap" the brake before certain corners when haulin-***, like during TT events.

Note: I have removed my Yaw sensor from my 2006 Grand Touring with ATE Blue and CarboTeck XP10s...car only has 15k miles, so I don't THINK the hubs are a problem...but I could be wrong and I do carry a pair of spare front hubs (and rear bearing)

I have also had "Hard pedal" before, but removing the Yaw sensor appears to have resolved that problem...
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Old Jun 18, 2008 | 04:59 AM
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yeah most guys just tap the brakes on straights before big corners to check for pedal.
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Old Jun 18, 2008 | 06:18 AM
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Originally Posted by laze1
I don't know if I have had "pad knock-back" but I have experience "NO PEDAL" on occasions. On a few occasions I would hit the brake and the pedal go WAY DOWN,,,then the problem wouldn't happen again the entire weekend. But this was NOT brake fade, just NO PEDAL
Yeah, that is knockback. That pads are getting pushed back, and then your first application of the brakes is pushing the pads back towards the rotor.

Anyways, thanks to everyone for all the comments on left foot tapping, or how you personnally have never experienced knockback, or how its not the brakes, its the wheel bearings.

However, all that is irrelevant. The design of the 350Z/G35 contributes greatly towards knockback, even with perfect whell bearings. A large BBK also helps contribute to it. It's a real thing, and even if you personnaly are not getting it, doesn't mean it's not happening.

As for the left foot tap, yes, that is a valid solution, but I am looking for a beter one, hence knockback springs.

What I really want to know is from people who do run knockback springs (and there are some who do), how much increased pad and rotor wear you are getting. If you aren't running knockback springs (and haven't run them), then really, your opinion on whether or not knockback is occuring is rather worthless to me in the case of this question.
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Old Jun 18, 2008 | 10:36 AM
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Might try PM'ing Daveh, as I believe he is running some knock-back springs in his ST calipers.

Most knock-back springs are just wound piano wire, so you might also want to ask him how long he is able to run the springs before their spring load drops and they aren't as effective. If they need to be replaced every six months or so, that might be good to know.

Will
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