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

Pull to the left under hard braking

Thread Tools
 
Search this Thread
 
Old 05-04-2010, 06:53 PM
  #1  
Elite Member
Thread Starter
iTrader: (4)
 
MartinezA92's Avatar
 
Join Date: Aug 2009
Location: Redwood City, CA
Posts: 1,784
Total Cats: 42
Default Pull to the left under hard braking

I can't figure this **** out.

I just put on new rotors and pads on the front. I bed them in etc. etc.
Under hard braking I get a pull to the left. After some inspection, its fairly obvious that the LF is working harder than the RF. The wear pattern on the LF rotor is pretty well established, the RF rotor still has some machining marks on it. I change the caliper on the RF with one I had laying around. Same ****.
I bleed the system. 3 times.

I'm about to swap the rotors and pads from side to side and see what happens.

Could this have anything to do with the MC?
Any ideas? ***** bugging the hell out of me.
MartinezA92 is offline  
Old 05-04-2010, 06:55 PM
  #2  
Junior Member
iTrader: (1)
 
stranges12712's Avatar
 
Join Date: May 2009
Location: Niagara Falls, ON
Posts: 431
Total Cats: 2
Default

The only thing i can think that would do that is siezed slider bolts...did you clean and lube them?
stranges12712 is offline  
Old 05-04-2010, 07:01 PM
  #3  
Elite Member
Thread Starter
iTrader: (4)
 
MartinezA92's Avatar
 
Join Date: Aug 2009
Location: Redwood City, CA
Posts: 1,784
Total Cats: 42
Default

Yep, multiple times.
MartinezA92 is offline  
Old 05-04-2010, 07:09 PM
  #4  
Junior Member
iTrader: (1)
 
stranges12712's Avatar
 
Join Date: May 2009
Location: Niagara Falls, ON
Posts: 431
Total Cats: 2
Default

Hmmm, im thinking a bad caliper. The one you threw in was it new? Cause if your bleeding them and your getting fluid through the caliper its not the master, if it was the master your pedal would go to the floor.
stranges12712 is offline  
Old 05-04-2010, 07:12 PM
  #5  
Junior Member
iTrader: (3)
 
alik's Avatar
 
Join Date: Nov 2007
Location: Boston / '90 Mariner Blue
Posts: 330
Total Cats: 14
Default

I suspect cheesy master. On Miatas, proportioning valve only deals with rear lines (if my memory is good for anything).
You're getting different flow (volume) to LF than RF. Change master, and tell us.
alik is offline  
Old 05-04-2010, 07:15 PM
  #6  
Elite Member
Thread Starter
iTrader: (4)
 
MartinezA92's Avatar
 
Join Date: Aug 2009
Location: Redwood City, CA
Posts: 1,784
Total Cats: 42
Default

Thats what I was thinking, is the split a diagonal split? As in if my RF isn't getting sufficient pressure, my LR probably isn't either?
MartinezA92 is offline  
Old 05-04-2010, 07:20 PM
  #7  
Elite Member
iTrader: (7)
 
turotufas's Avatar
 
Join Date: Jul 2009
Location: Gainesville,Fl
Posts: 3,304
Total Cats: 7
Default

And it was working perfectly before? How are the brake lines, check them then look at the calipers.
turotufas is offline  
Old 05-04-2010, 07:22 PM
  #8  
Elite Member
Thread Starter
iTrader: (4)
 
MartinezA92's Avatar
 
Join Date: Aug 2009
Location: Redwood City, CA
Posts: 1,784
Total Cats: 42
Default

It seems to have slowly gotten worse, replaced the front lines with steel lines, no leaks.
MartinezA92 is offline  
Old 05-04-2010, 07:25 PM
  #9  
Junior Member
iTrader: (3)
 
alik's Avatar
 
Join Date: Nov 2007
Location: Boston / '90 Mariner Blue
Posts: 330
Total Cats: 14
Default

Don't think so.
I've been playing so much with my Galant VR-4, that my memory is fuzzy.
Besides, with Miata in the garage, there's nothing to look at.

But, going by manual, the master supplies fluid to LF, RF, and rear. Rear is fed through prop valve. I think the pressure is split only front/rear.

Check your rotors in the rear.
And, swap the master.
alik is offline  
Old 05-04-2010, 07:28 PM
  #10  
Elite Member
Thread Starter
iTrader: (4)
 
MartinezA92's Avatar
 
Join Date: Aug 2009
Location: Redwood City, CA
Posts: 1,784
Total Cats: 42
Default

Isn't the Miatas system wayyy biased towards the front anyway? My rears took forever to get a wear pattern on them last time I changed the rotors.
MartinezA92 is offline  
Old 05-04-2010, 07:32 PM
  #11  
Junior Member
iTrader: (3)
 
alik's Avatar
 
Join Date: Nov 2007
Location: Boston / '90 Mariner Blue
Posts: 330
Total Cats: 14
Default

Yep.
But, your problem isn't that the rear isn't locking. If that, then I'd look at prop valve.

The problem is uneven pressure distribution. Faulty master (I'm guessing).

Start by replacing it, and not spending time on Internet forums.
alik is offline  
Old 05-04-2010, 07:49 PM
  #12  
mkturbo.com
iTrader: (24)
 
shuiend's Avatar
 
Join Date: May 2006
Location: Charleston SC
Posts: 15,177
Total Cats: 1,681
Default

Have you checked your tires? I had a newer tire on the front right of my integra and it would pull slightly to the right while driving.
shuiend is offline  
Old 05-04-2010, 07:53 PM
  #13  
Junior Member
iTrader: (3)
 
alik's Avatar
 
Join Date: Nov 2007
Location: Boston / '90 Mariner Blue
Posts: 330
Total Cats: 14
Default

He says it's only under hard braking.
alik is offline  
Old 05-04-2010, 07:56 PM
  #14  
Tour de Franzia
iTrader: (6)
 
hustler's Avatar
 
Join Date: Jun 2006
Location: Republic of Dallas
Posts: 29,085
Total Cats: 375
Default

are the bleeders tight? I chased this issue on my wilwoods, only 10-failure points between the pair!!!
hustler is offline  
Old 05-04-2010, 08:37 PM
  #15  
Elite Member
Thread Starter
iTrader: (4)
 
MartinezA92's Avatar
 
Join Date: Aug 2009
Location: Redwood City, CA
Posts: 1,784
Total Cats: 42
Default

Yep, bleeders are tight. Just swapped back to the old caliper that isn't painted VTEC Red. Swapped pads and rotors side to side. Gonna see what happens. MC is on order.
MartinezA92 is offline  
Old 05-04-2010, 08:56 PM
  #16  
Elite Member
iTrader: (5)
 
m2cupcar's Avatar
 
Join Date: Jan 2005
Location: Atlanta
Posts: 7,486
Total Cats: 372
Default

I had the same problem. It was the OE bushings coming apart on the bottom front control arms at the camber bolts. It was pulling right and about half of one the bushings had come out, so I was get some big toe out under heavy front load. No fun on a roval.
m2cupcar is offline  
Old 05-04-2010, 09:09 PM
  #17  
y8s
2 Props,3 Dildos,& 1 Cat
iTrader: (8)
 
y8s's Avatar
 
Join Date: Jun 2005
Location: Fake Virginia
Posts: 19,338
Total Cats: 573
Default



does it have brakes like this?


...


sorry. i had to.
y8s is offline  
Old 05-04-2010, 10:26 PM
  #18  
Elite Member
Thread Starter
iTrader: (4)
 
MartinezA92's Avatar
 
Join Date: Aug 2009
Location: Redwood City, CA
Posts: 1,784
Total Cats: 42
Default

Those are top quality race brakes right there.

So I switched pads/rotors from side to side. Now I have a pull to the right. The rotor with not much of a wear pattern on it has a strange yellow hue towards the center.

Wtf?
MartinezA92 is offline  
Old 05-04-2010, 11:10 PM
  #19  
Supporting Vendor
iTrader: (3)
 
ThePass's Avatar
 
Join Date: Jul 2006
Location: San Diego
Posts: 3,303
Total Cats: 1,216
Default

It's your tire pressures.
__________________
Ryan Passey
ThePass is offline  
Old 05-04-2010, 11:13 PM
  #20  
Senior Member
iTrader: (23)
 
Jfornachon's Avatar
 
Join Date: Oct 2009
Location: Chatsworth, SoCal
Posts: 948
Total Cats: 1
Default

I would machine the rotors and try some dofferent pads. Also check measure the rotor thickness to confirm that onw rotor is not way thicker than the otheri

What is the wear on the left side like now? Is it starting to wear a little better? One might be beded a little better than the other. Drive it for a but to see if the left will come in. What kind of pads are you running? Report back after a little more driving.

Have a great day,
Jared
Jfornachon is offline  


Quick Reply: Pull to the left under hard braking



All times are GMT -4. The time now is 09:11 AM.