Suspension, Brakes, Drivetrain discuss the wondrous effects of boost and your miata...
Sponsored by:
Sponsored by:

Wilwood Dynapro Pad Knockback issue.

Thread Tools
 
Search this Thread
 
Old 07-04-2017, 02:57 AM
  #1  
Elite Member
Thread Starter
 
icantlearn's Avatar
 
Join Date: Sep 2015
Location: San Jose, CA
Posts: 1,939
Total Cats: 117
Default Wilwood Dynapro Pad Knockback issue.

Hi Guys, I am having a strange issue with my brakes. When driving aggressively, I get pad knock back, however, I already replaced my front hubs and the issue is still there. I really don't think it is the rear because of the amount of travel needed to engage the brakes again. Any ideas?
icantlearn is offline  
Old 07-04-2017, 12:20 PM
  #2  
SADFab Destructive Testing Engineer
iTrader: (5)
 
aidandj's Avatar
 
Join Date: Apr 2014
Location: Beaverton, USA
Posts: 18,642
Total Cats: 1,866
Default

Try driving aggressively then stop without using the front brakes (e brake or coasting) and measure the gap between pads and rotors.
aidandj is offline  
Old 07-04-2017, 12:46 PM
  #3  
Elite Member
iTrader: (4)
 
hornetball's Avatar
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,301
Total Cats: 696
Default

Why don't you think it's the rears? Rear hubs crack. Have you inspected them?
hornetball is offline  
Old 07-04-2017, 12:50 PM
  #4  
Elite Member
Thread Starter
 
icantlearn's Avatar
 
Join Date: Sep 2015
Location: San Jose, CA
Posts: 1,939
Total Cats: 117
Default

Originally Posted by aidandj
Try driving aggressively then stop without using the front brakes (e brake or coasting) and measure the gap between pads and rotors.
I will try this today. Another thing to note is that the pads contact the rotors when I am off the brakes, especially the rears. I can hear them squeak until I pull the handbrake up and it goes away. Same with the front but it is not as bad.
icantlearn is offline  
Old 07-04-2017, 12:51 PM
  #5  
Elite Member
Thread Starter
 
icantlearn's Avatar
 
Join Date: Sep 2015
Location: San Jose, CA
Posts: 1,939
Total Cats: 117
Default

Originally Posted by hornetball
Why don't you think it's the rears? Rear hubs crack. Have you inspected them?
I have inspected them, they look and feel fine.
icantlearn is offline  
Old 07-04-2017, 06:52 PM
  #6  
Elite Member
Thread Starter
 
icantlearn's Avatar
 
Join Date: Sep 2015
Location: San Jose, CA
Posts: 1,939
Total Cats: 117
Default

Took the front wheels off. Everything looks fine. Rears have movement side to side but none in and out. Dunno.
icantlearn is offline  
Old 07-04-2017, 06:56 PM
  #7  
SADFab Destructive Testing Engineer
iTrader: (5)
 
aidandj's Avatar
 
Join Date: Apr 2014
Location: Beaverton, USA
Posts: 18,642
Total Cats: 1,866
Default

What do you mean side to side? And yeah rotors will contact pads. There are no springs to push them back.
aidandj is offline  
Old 07-04-2017, 06:59 PM
  #8  
Elite Member
Thread Starter
 
icantlearn's Avatar
 
Join Date: Sep 2015
Location: San Jose, CA
Posts: 1,939
Total Cats: 117
Default

The pads will move towards the front and rear of the car, but not from driver to passenger side. Same with front, but not as easily.
icantlearn is offline  
Old 07-22-2017, 07:54 PM
  #9  
Elite Member
Thread Starter
 
icantlearn's Avatar
 
Join Date: Sep 2015
Location: San Jose, CA
Posts: 1,939
Total Cats: 117
Default

Bueller?....anyone?
icantlearn is offline  
Old 07-27-2017, 01:41 PM
  #10  
Junior Member
 
Jumbosrule's Avatar
 
Join Date: Apr 2013
Location: Redondo Beach, CA
Posts: 86
Total Cats: 19
Default

Is this on track or on the street that you experience knockback?

It's known that the Miata knuckle flexes over about 1.2g (ish) in cornering... this is enough to cause knockback on track, especially if you have larger than stock rotors.

I assume you have a two-peice rotor with the Wilwood kit - does it appear to "wobble" when you spin it by hand without the wheel attached? Have you checked bolt torque on your caliper brackets?
Jumbosrule is offline  
Old 07-27-2017, 04:15 PM
  #11  
Elite Member
Thread Starter
 
icantlearn's Avatar
 
Join Date: Sep 2015
Location: San Jose, CA
Posts: 1,939
Total Cats: 117
Default

[QUOTE=Jumbosrule;1430231]Is this on track or on the street that you experience knockback?[\QUOTE]

Both. But only if I drive agressiveley in the street. Sudden right to left movement (sloloms) will do it every time.

[QUOTE]It's known that the Miata knuckle flexes over about 1.2g (ish) in cornering... this is enough to cause knockback on track, especially if you have larger than stock rotors.[\QUOTE]

Hmm. Did not know this. I am pulling over 1.2 for sure on track but not on the street.

Originally Posted by Jumbosrule
I assume you have a two-peice rotor with the Wilwood kit - does it appear to "wobble" when you spin it by hand without the wheel attached? Have you checked bolt torque on your caliper brackets?
It does not wobble. Have not checked bolt torque. But I would find it hard to believe that would be the issue
icantlearn is offline  
Old 07-27-2017, 05:13 PM
  #12  
Art
Junior Member
 
Art's Avatar
 
Join Date: Jul 2016
Posts: 369
Total Cats: -251
Default

.

Last edited by Art; 06-11-2018 at 05:58 PM.
Art is offline  
Old 07-27-2017, 07:38 PM
  #13  
Elite Member
Thread Starter
 
icantlearn's Avatar
 
Join Date: Sep 2015
Location: San Jose, CA
Posts: 1,939
Total Cats: 117
Default

Radial
icantlearn is offline  
Old 07-27-2017, 07:51 PM
  #14  
SADFab Destructive Testing Engineer
iTrader: (5)
 
aidandj's Avatar
 
Join Date: Apr 2014
Location: Beaverton, USA
Posts: 18,642
Total Cats: 1,866
Default

Originally Posted by MiataMan00
Radial Lug mount
FTFY
aidandj is offline  
Old 07-27-2017, 11:21 PM
  #15  
Elite Member
Thread Starter
 
icantlearn's Avatar
 
Join Date: Sep 2015
Location: San Jose, CA
Posts: 1,939
Total Cats: 117
Default

oh. I thought I read somewhere it was a radial mount. Guess I was wrong. Thanks Adian.
icantlearn is offline  
Old 07-27-2017, 11:46 PM
  #16  
Elite Member
 
codrus's Avatar
 
Join Date: Mar 2007
Location: Santa Clara, CA
Posts: 5,165
Total Cats: 855
Default

The Dynapro is available in both radial and lug mount forms. The TSE kit is lug mount because that's more convenient (it bolts up to the same bracket as the Dynalite) and because most of the stiffness improvements from radial mount calipers really only apply if you've got an upright with radial mounting holes on it.

--Ian
codrus is offline  
Old 07-28-2017, 02:24 AM
  #17  
Senior Member
iTrader: (1)
 
NiklasFalk's Avatar
 
Join Date: Jun 2006
Location: Sweden
Posts: 1,391
Total Cats: 63
Default

They both have the name "Dynapro" but have noticeable differences in dimensions.


Both requires adapters but the radial mount caliper itself "feels" beefier (longer and wider).
NiklasFalk is offline  
Old 07-28-2017, 05:28 AM
  #18  
Art
Junior Member
 
Art's Avatar
 
Join Date: Jul 2016
Posts: 369
Total Cats: -251
Default

.

Last edited by Art; 06-11-2018 at 05:58 PM.
Art is offline  
Reply
Leave a poscat -1 Leave a negcat
Old 07-28-2017, 01:59 PM
  #19  
Elite Member
 
bbundy's Avatar
 
Join Date: Jul 2005
Location: Anacortes, WA
Posts: 2,478
Total Cats: 144
Default

Originally Posted by codrus
The Dynapro is available in both radial and lug mount forms. The TSE kit is lug mount because that's more convenient (it bolts up to the same bracket as the Dynalite) and because most of the stiffness improvements from radial mount calipers really only apply if you've got an upright with radial mounting holes on it.

--Ian
The lug mount and the radial Dynapro calipers are radically different and don't even use the same pads. There is almost no difference whatsoever in performance between a Lug mount Dynapro and a Cheap lug mount Dynalite. The radial Dynapro however is a drastic upgrade. 50% more pad life because they are thicker, the caliper design is much stiffer with bigger bolts holding the halves together on a larger spread bolt pattern, and it allows for better clearance in the radial direction for stuffing big rotors in small wheels by almost 5mm.
bbundy is offline  
Old 07-28-2017, 08:49 PM
  #20  
Elite Member
Thread Starter
 
icantlearn's Avatar
 
Join Date: Sep 2015
Location: San Jose, CA
Posts: 1,939
Total Cats: 117
Default

Originally Posted by bbundy
The lug mount and the radial Dynapro calipers are radically different and don't even use the same pads. There is almost no difference whatsoever in performance between a Lug mount Dynapro and a Cheap lug mount Dynalite.
Then why do they make the lug mount dynapro? That makes no sense.
icantlearn is offline  



All times are GMT -4. The time now is 12:04 PM.