wearymicrobe
wearymicrobe Dork
10/17/12 10:04 p.m.

Ok I feel like a idiot. I have new Pagid orange pads on the Viper. Rear pads are fine currently, front pads not so much. Effectively a bunch of low speed squeaking.

The rotors are showing a weird effect on the front, the rust on the inner say two inches is removed with some driving but the rest of the rotor is as rusty as all heck to me meaning that I have no contact with the rotor at lets say 75+% of the rotor.

I have a lot of brakes, more then enough to lock things up currently.

I have done the usual 60mph down to 20mph X 8 bedding in process with no luck in getting the pads to lay flat against the rotor. Might be that I cannot get enough heat into them with my brake vents.

I would normally say its due to the lack of beveling like a factory pad, or riding on the edge of the rotor. But I usually get chatter when that is the case. Rotors spec out clean and its happening on both front rotors so its unlikely that they worn in some sort of pattern.

Any idea's.

CGLockRacer
CGLockRacer HalfDork
10/18/12 6:20 a.m.

Some pad manufacturers say to block off cooling vents when bedding. Also, have you run this brand of pad before? New rotors?

stumpmj
stumpmj Dork
10/18/12 8:13 a.m.

Yes, block the cooling ducts. Those pads are supposed to get HOT durring the bedding process.

I'm still concerned though. Temperature shouldn't be affecting the amount of pad contacting the rotor. Can you post a picture to make sure we're all clear on what's happening?

wearymicrobe
wearymicrobe Dork
10/18/12 9:25 a.m.

Looks like this. Maybe sticking brake pins

GameboyRMH
GameboyRMH PowerDork
10/18/12 10:59 a.m.

Yeah hot brakes or not something is wrong, the pads aren't making full contact.

wearymicrobe
wearymicrobe Dork
10/18/12 11:18 a.m.

I am going to grease the pins and block off the cooling vents and try and re-bed them tonight. I can recheck the runout and see if the rotor thickness is off but I really doubt it.

stumpmj
stumpmj Dork
10/18/12 2:28 p.m.

How much time on the rotors? That's exactely how rotors look on my street cars before I replace the rotors. If it was my race/track car, I'd put a new set of rotors on it and rebuild the calipers. Don't screw around with brakes.

Cone_Junky
Cone_Junky Dork
10/18/12 2:31 p.m.

Sounds like your rotors are dished. If you just did a pad swap, that would explain the uneven contact surface. Cut the rotors or replace and repeat bedding process.

motomoron
motomoron Dork
10/18/12 3:26 p.m.

60-20 mph seems slow- to get good transfer of the layer of magic onto the rotor I've usually done maybe 6 braking events of 90-50 mph medium hard followed by a little cool off then a couple efforts like I'm qualifying.

From www.pagidusa.com

Why bedding?

To transfer a layer of friction material onto the brake disc faces to achieve maximum performance. To stabilize compressible materials to avoid a spongy pedal. To boil off volatile elements in the friction compound in order to have the initial ‘green’ fading during bedding and not during the race. To align the pad surface with the brake disc surface to have full contact. If pads do not get bedded properly and / or used to hard right out of the box will likely lead to pad glazing. Pad glazing is a condition where the resins in the pad crystallize on both, the pad friction surface and the brake disc surface, resulting in poor stopping performance, brake judder and vibrations. Also rapidly escaping volatile elements and moisture from the resin would seek an immediate escape route out of the friction compound, creating small fissures that would lead shortly to cracking and chunking.

1.) BASIC BEDDING IN To initiate some heat in the brake discs and pads.

4 to 6 stops with medium brake pressure from approximately 150 km/h (90 MPH) to approximately 80 km/h (50 MPH). Distance between each brake stop approximately 300 - 400 meters (300 to 400 yards). The pads should not reach temperatures above 400° Centigrade (550° Fahrenheit). No dragging! Blocking of the air ducts might be helpful to reach appropriate temperatures quicker.

2.) IMMEDIATELY AFTER BASIC BEDDING IN AT HIGH SPEED Simulating race conditions One stop with medium to heavy brake pressure, without allowing brakes to lock from approximately 180 km/h (110 MPH) to approximately 80 km/h (50 MPH). No dragging! Recovery stops with light brake pressure 3 to 4 times. (Cleaning procedure) Repeat the high-speed stops including recovery stops 2 to 3 times. Allow a cool-off distance of approximately 500 m (500 yards) between high-speed stops.

BRAKE DISCS If possible, pads should be bedded on used but NOT worn out brake discs. Pagid brake pad material can be used either on solid, grooved or cross-drilled discs. For disc bedding please refer to the disc manufacturers’ own instruction.

MOUNTING NEW PADS ON USED DISCS Edges of pad surface should be filed roughly to 45 degrees to ensure that the pad carries fully and evenly and is not touching the edge of the disc. Do not use discs, which are pre-bedded, or have been used with friction material other than PAGID.

wbjones
wbjones UltraDork
10/18/12 4:29 p.m.

while I agree with motomoron on the tips to pad bedding I nearly choked with laughter at his speed recommendations .. it takes the full straight-away at CMP ( flat footing it through the kink) to reach his 90 mph and the entire back stretch at VIR to not quite make the 110 mph .... full disclosure: it's a 100whp CRX

I've had fairly good success with the 60 - 20 done 5 - 8 times then drive around without using the brakes for about 5 min and redo ... this is with either Hawk DTC60's or Carbotech XP 10's

here are a couple of other takes on bedding :

http://www.essexparts.com/learning-center/cat/brake-rotors/post/Bed-in

http://www.essexparts.com/learning-center/swapping_pads

Kenny_McCormic
Kenny_McCormic Reader
10/18/12 4:52 p.m.

My bedding procedure is to work the brakes till I can smell them doing 60-10-60 runs closer and closer together, then do not go below walking speed for 5+ miles. Of course with more expensive pads on a car that I imagine runs some pretty expensive rotors, you might want to be a bit more scientific.

wearymicrobe
wearymicrobe Dork
10/18/12 5:35 p.m.
Cone_Junky wrote: Sounds like your rotors are dished. If you just did a pad swap, that would explain the uneven contact surface. Cut the rotors or replace and repeat bedding process.

I only have 2K on the rotors and non of that is track time. I cannot think how I could dish or damage them in that time.

Something weird is definitely going on. I flushed them with water today and got 10x the normal brake dust blown out.

stumpmj
stumpmj Dork
10/19/12 8:47 a.m.

Only 2000 miles on the rotors... Who made them?

How many miles on the calipers and how much of that was track time? Do Vipers suffer from caliper flex issues?

wearymicrobe
wearymicrobe Dork
10/19/12 9:20 a.m.
stumpmj wrote: Only 2000 miles on the rotors... Who made them? How many miles on the calipers and how much of that was track time? Do Vipers suffer from caliper flex issues?

Stoptech on the rotor, the factory ACR versions.

I am going to grab a infrared temp gauge at the office and see how hot I can get them. I did another bedding in last night at sane speeds and they are looking better but I doubt they got above 300 degrees.

motomoron
motomoron Dork
10/19/12 9:58 a.m.
wbjones wrote: while I agree with motomoron on the tips to pad bedding I nearly choked with laughter at his speed recommendations .. it takes the full straight-away at CMP ( flat footing it through the kink) to reach his 90 mph and the entire back stretch at VIR to not quite make the 110 mph .... full disclosure: it's a 100whp CRX I've had fairly good success with the 60 - 20 done 5 - 8 times then drive around without using the brakes for about 5 min and redo ... this is with either Hawk DTC60's or Carbotech XP 10's here are a couple of other takes on bedding : http://www.essexparts.com/learning-center/cat/brake-rotors/post/Bed-in http://www.essexparts.com/learning-center/swapping_pads

All you guys with slow cars need to get faster cars.

Mister Microbe has a Viper, and a fast Viper at that. He could do the 0-110-50 cycles on my cul-de-sac, not problem.

Also, for what it's worth, here's my giant fleet of money-sucking parasites listed in order of displacement:

  • RD400 - 400cc

  • KTM 690 SMC - 640cc

  • Sprite - 1275cc

  • Radical - 1300cc

  • Miata - 1600cc

  • 525iT - 2500cc

  • Wife's A4 - 2800cc

  • M3 - 3200cc

  • Tacoma - 3400cc

So it's not like I'm a big-motor junkie. My old 3.9 V6 Dakota was the biggest thing I've ever had.

wbjones
wbjones UltraDork
10/20/12 6:23 p.m.
motomoron wrote:
wbjones wrote: while I agree with motomoron on the tips to pad bedding I nearly choked with laughter at his speed recommendations .. it takes the full straight-away at CMP ( flat footing it through the kink) to reach his 90 mph and the entire back stretch at VIR to not quite make the 110 mph .... full disclosure: it's a 100whp CRX I've had fairly good success with the 60 - 20 done 5 - 8 times then drive around without using the brakes for about 5 min and redo ... this is with either Hawk DTC60's or Carbotech XP 10's here are a couple of other takes on bedding : http://www.essexparts.com/learning-center/cat/brake-rotors/post/Bed-in http://www.essexparts.com/learning-center/swapping_pads
All you guys with slow cars need to get faster cars.

I've been told this before

someday... assuming I get tired of a-x I'll probably do a motor swap ... B18 or a K sumpum sumpum .... that should make it so I don't do all my driving in my mirrors

wearymicrobe
wearymicrobe Dork
10/20/12 8:03 p.m.
wbjones wrote: while I agree with motomoron on the tips to pad bedding I nearly choked with laughter at his speed recommendations .. it takes the full straight-away at CMP ( flat footing it through the kink) to reach his 90 mph and the entire back stretch at VIR to not quite make the 110 mph .... full disclosure: it's a 100whp CRX I've had fairly good success with the 60 - 20 done 5 - 8 times then drive around without using the brakes for about 5 min and redo ... this is with either Hawk DTC60's or Carbotech XP 10's here are a couple of other takes on bedding : http://www.essexparts.com/learning-center/cat/brake-rotors/post/Bed-in http://www.essexparts.com/learning-center/swapping_pads

I have almost 7 times the HP of your CRX, and more then likely 25-30% more weight I am going a bit faster then you might on the same track. 640/700 hp/tq at 3240lb's dry and short rear gears should get me up to speed decently well.

So couple things I blocked off the brake cooling, and then did some freeway driving and let the brakes drag a bit while accelerating. That got some real heat in according to the laser. Then found a big, long, straight and empty stretch of road and did "some" 120-0 stop's.

Short answer is success, I still have a few 1-2mm small rings on the front that might need a few more cycles. Some track time and some real heat will fix that.

I am going to put the street rotors back on later this weekend if I have a chance.

Not sure if the ABS is stopping the pads from bedding in as fast as I would like, or that the pads are extremely hard, or that the car just stops so violently that the contact time on the pads is not significant, or the rotors are hard, or I am getting pad material buildup becuase they are new.

But apparently the answer was " MORE POWER", which is very fitting.

wbjones
wbjones UltraDork
10/21/12 9:31 a.m.
wearymicrobe wrote:
wbjones wrote: while I agree with motomoron on the tips to pad bedding I nearly choked with laughter at his speed recommendations .. it takes the full straight-away at CMP ( flat footing it through the kink) to reach his 90 mph and the entire back stretch at VIR to not quite make the 110 mph .... full disclosure: it's a 100whp CRX I've had fairly good success with the 60 - 20 done 5 - 8 times then drive around without using the brakes for about 5 min and redo ... this is with either Hawk DTC60's or Carbotech XP 10's here are a couple of other takes on bedding : http://www.essexparts.com/learning-center/cat/brake-rotors/post/Bed-in http://www.essexparts.com/learning-center/swapping_pads
I have almost 7 times the HP of your CRX, and more then likely 25-30% more weight I am going a bit faster then you might on the same track. 640/700 hp/tq at 3240lb's dry and short rear gears should get me up to speed decently well. So couple things I blocked off the brake cooling, and then did some freeway driving and let the brakes drag a bit while accelerating. That got some real heat in according to the laser. Then found a big, long, straight and empty stretch of road and did "some" 120-0 stop's. Short answer is success, I still have a few 1-2mm small rings on the front that might need a few more cycles. Some track time and some real heat will fix that. I am going to put the street rotors back on later this weekend if I have a chance. Not sure if the ABS is stopping the pads from bedding in as fast as I would like, or that the pads are extremely hard, or that the car just stops so violently that the contact time on the pads is not significant, or the rotors are hard, or I am getting pad material buildup becuase they are new. But apparently the answer was " MORE POWER", which is very fitting.

yeah, I'm aware of the 7x hp ... a Viper Cup Car passed me on the back stretch at VIR ... it literally pushed me sideways a full car width with the air it was pushing ....just WOW ...

as for the ABS being a problem can you pull the ABS fuze when doing your brake bedding ?

wearymicrobe
wearymicrobe Dork
10/21/12 10:30 a.m.
wbjones wrote:
wearymicrobe wrote:
wbjones wrote: while I agree with motomoron on the tips to pad bedding I nearly choked with laughter at his speed recommendations .. it takes the full straight-away at CMP ( flat footing it through the kink) to reach his 90 mph and the entire back stretch at VIR to not quite make the 110 mph .... full disclosure: it's a 100whp CRX I've had fairly good success with the 60 - 20 done 5 - 8 times then drive around without using the brakes for about 5 min and redo ... this is with either Hawk DTC60's or Carbotech XP 10's here are a couple of other takes on bedding : http://www.essexparts.com/learning-center/cat/brake-rotors/post/Bed-in http://www.essexparts.com/learning-center/swapping_pads
I have almost 7 times the HP of your CRX, and more then likely 25-30% more weight I am going a bit faster then you might on the same track. 640/700 hp/tq at 3240lb's dry and short rear gears should get me up to speed decently well. So couple things I blocked off the brake cooling, and then did some freeway driving and let the brakes drag a bit while accelerating. That got some real heat in according to the laser. Then found a big, long, straight and empty stretch of road and did "some" 120-0 stop's. Short answer is success, I still have a few 1-2mm small rings on the front that might need a few more cycles. Some track time and some real heat will fix that. I am going to put the street rotors back on later this weekend if I have a chance. Not sure if the ABS is stopping the pads from bedding in as fast as I would like, or that the pads are extremely hard, or that the car just stops so violently that the contact time on the pads is not significant, or the rotors are hard, or I am getting pad material buildup becuase they are new. But apparently the answer was " MORE POWER", which is very fitting.
yeah, I'm aware of the 7x hp ... a Viper Cup Car passed me on the back stretch at VIR ... it literally pushed me sideways a full car width with the air it was pushing ....just WOW ... as for the ABS being a problem can you pull the ABS fuze when doing your brake bedding ?

I am always worried about flat spotting the tires when I do this, they are mondo expensive. Slapped the stock rotors on last night, will see what happens when I get another track day in.

wbjones
wbjones UltraDork
10/21/12 12:10 p.m.

keep in mind that a "chirping" lock-up isn't really flat spotting your tires ( and yeah I understand how pricy those big boy tires are ) but remember that you can modulate the brake pedal ( and I do know how great the braking force is on those cars ) so that you are whoa-ing down just short of ABS ( with or without the fuze ) ....

or you could just wait for the next track day

are you doing PDX's or is it TT ... if TT then you can usually use the first session to bed brakes, or do an initial heat cycle on a new set of tires .... if you are going to do that I'd still recommend closing off the ducting to the brakes .... one or two laps, then cruise along without touching the brakes for a lap then come in, park it and let them cool. then you're ready for the next session at full song

wearymicrobe
wearymicrobe Dork
11/12/12 9:52 a.m.

So I finally got this worked out. Pads turned out to be Hawk DTC-70's. Which explains the noise and the absolute refusal to bed.

I had the rotors resurfaced just to be safe, and I flattened out the pads on some 200 grit on big piece of flat marble. No more rings after about a 2 minute drive.

But they squeal like a pig stuck in a combine.

It's drop dead embarrassing, there is no chance in the world I could slap these on and drive to the track. Plus if the internet is to be believed the Hawk full race pads destroy your rotors if not up to temp, IE 500+.

After I bedded them in though they stop like nothing I have ever felt, its like the hand of god just grabs you by the nuts . The whole car actually dives down on the suspension starts yanking you backwards cleanly and evenly.

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