Friend's car is an 8th gen Civic swapped with K20Z3.

AP 4-pot Caliber with AP slotted rotor and Mintex pads, temp range 0-500C*.

The pads were driven lightly for a hundred miles or so, and shakes pretty bad.

Then I recommended to bed in the pads properly first. The pads were then bedded in with 70mph - 20 mph hard braking 6 times, left-foot brake grinding for 1 minute and drove back with no brakes and parked for 12 hours of cool down.

Most of the shaking at low speed and high speed are now gone, but at around 80mph, when lightly apply braking, it shakes/rumbles again, but once more brake pressure is applied, the shaking will go away.

What can be the possible causes? The AP rotor is spanking new, can't be warped, the bolts were properly torqued, and the wheels are well-balanced.





Modified by nEoMuGen at 1:12 AM 1/24/2008

 

Because someone will undoubtedly tell you, I'll get it out of the way. "Warped" rotors are actually an uneven transfer of pad material onto the rotor, not a physical waviness of the rotor itself. So brand new or not, improper bedding can result in that shuddering. I have no idea what the recommended thing is for Mintex pads, but I'm used to a few slower speed, less aggressive stops, followed by the higher speed more aggressive stops, followed immediately by a cool down drive, and then parking it. You might want to turn the rotors for a clean surface, then try it again a different way.

Also, unrelated to the shuddering 500* upper temp range is pretty low for a track pad. As an example, the street/track Cobalt GT-Sport is rated at 50-1200*F. That's a HUGE difference over yours.

 

Yes, I am well awared that film transfer should be the main cause here. But shouldn't the shuttering appear no matter the speed nad force when the brake is applied? The shuttering we have now only appear at 80+mph, and the brake pedal pressed lightly.

The bed-in process actually were done 2 times, on two consecutive nights. Gradual hard braking with cool downs.

But there are still visible residue on the brake dics, the "black spots". The pads and discs were lightly sanded today to get rid of residue, but the light shaking at 80mph is still there.

And sorry for not being clarified, the pad is not a track pad but a street pad, and I made a mistake that 500 degrees is Celsius, not Farenheit.

 

Wait a minute...how the hell did I forget your SN, you're Ray right? Like back-in-the-day R-Speed Ray? This is Adam, formerly "sscguy" if you remember.

Anyway, to your question, I had some track pads that had a similar situation to yours, and the shuddering went away after more use. I never figured out exactly what the problem was, so I don't know how much help that is.

 

LMAO! Yep, that's me, I havn't been around H-T for years now since I moved outta country to the sake of my career.

Where I'm at now (China), the race/mod scene here is way different back in the US. The parts ppl use here are mostly European, I'm clueless to most of them.

Anyway, I told my friend this isn't a major deal, he's just **** about it everyday.

I'll see if another bed-in + turning the rotor can fix the problem.

If not, I think the Mintex pad material are quite unstable to have so many residue, I already suggested him to get a cheap EBC green to test and isolate the problem ASAP.

I'm sure you progressed greatly in the motorsports scene...

Sigh...I havn't see any action for years now, and drives an Opel van for daily commute. Sad life


Modified by nEoMuGen at 1:31 AM 1/24/2008

 

Yeah, I think turning + rebedding would be your best bet. I don't know wtf to suggest if that doesn't work.

I'm instructing now, and just moved to Chicago

I have to say though, it is sad to think about you driving a damn van

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Stinkycheezmonky &raquo;</TD></TR><TR><TD CLASS="quote">


I have to say though, it is sad to think about you driving a damn van </TD></TR></TABLE>

Quite miserable indeed, but look at the bright side: It got a stick, LOL!

 

what up ray!!
&lt;--spenc
sounds like bad bedding. id try to bed again but do not left foot them. if not, you may have to try new rotors.

 

werd y0! I'd do that...

 

I had the same problem with our Big Rotora setup. shuddered very badly when braking from speed.
Turned the rotors fitted the same pads and everything was perfect!

Kiwi

 

Thanks, will try.