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Discussion Starter #1
So last fall, I put Raybestos St-43 pads on the car for the track. Kept them on for hibernation and Spring driving. I heard rubbing coming from somewhere and I was getting a ton of brake dust on the wheels. Took the wheel off and the pads were right up against the rotor and were causing an annoying rubbing sound. My question is, "is this normal with a track pad or did I so something wrong." The rubbing was annoying so I decided to put the OEM pads back on the front. Haven't gotten to the back pads yet but I can't imagine that having different pads on the front versus the back would be much of an issue with street driving, right?

Thanks in advance,
LMM
:confused:
 

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just a guess, I am not a mechanic nor do i claim much expertise.

perhaps the thickness of the new pads vs the used stock pads is displacing fluid back to the master cyliner making the pedal "depresed" if that makes sense.
check the level of fluid in the reservior(if its high after putting in the newer pads you would need to remove a bit to the max fill line and they might work w/o rubbing.
just a wild guess............
my mechanical advice is free, and its worth what you are paying for it.
 

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Does your wheel spin freely when the brakes are not applied? Are they hanging up?? I just witnessed a master cylinder failure on an 05 elise where the master cylinder was not returning to the open position and dragging the pads and during a flush it actually stuck in a depressed position until we manually pulled the piston back to the open position.
 

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Discussion Starter #4
Fishguy,

When I took out the OEM pads, they probably only had around 3k miles on them so they were probably still pretty thick. I took out the raybestos yesterday and put the oem pads back in so I can't check out the fluid levels now but I will make a mental note of it for next time. The OEM pads I just put back in were thicker than the raybestos which is kinda strange since they were used much less than OEM. I guess all that rubbing took a toll on the raybestos pads.

Ztec,

The rotors were spinning with the raybestos in, but they were not spinning freely, they were making a hissing sound as the pads were still right up against the rotors. I haven't driven the car with the oem pads back in but I'll give it a little spin today and see if the OEMs make the same rubbing sound. If they do, I'll take the car to a mechanic.

Thanks guys and I'll keep you posted.

LMM
 

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When I took out the OEM pads, they probably only had around 3k miles on them so they were probably still pretty thick. I took out the raybestos yesterday and put the oem pads back in so I can't check out the fluid levels now but I will make a mental note of it for next time.
what i mean is to check the level of the fluid in the master cylinder. that is just a visual inspection to see where the level of the fliud is. if its above the max fill line. this could be making your pistons not allowed to go back to their fully open position and create a rubbing on the rotors. if its the case, just take a syringe or something and remove the excess fuild until you are level with the max fill line.
I hope that makes sense.
 

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Have you followed the bedding procedures recommended by Raybestos?

xtn
 

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Discussion Starter #7
Fishguy,

Just checked and yes, the level is above Max. Will have to take some out....Thx.

xtn...I don't know of any bedding recommendations by Raybestos. The pads didn't come with any and the shop I bought from didn't know of any bedding procedures. This is the method I used. I drove it around for 10 min to get everything warm and then I broke heavily up from 20mph to a rolling stop and did that in increments of 10 mph to around 60mph or 70 mph to zero. On the last run, I slammed on them until stopped and then kept on the brakes for around 30 seconds or a minute while stopped. After that, I rode around another 15 minutes and that was it. I am going to do this to bed in the OEM pads.

Thanks guys.
 

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Uh... I've never heard of ANY pad manufacturer recommending to get them nice and hot and then sit still with the brakes applied. That's a big no-no.

xtn
 

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"With new pads and discs, or just new pads fitted run the car around for 10/20 miles using the brakes gently as normal to bed the two surfaces together. Once this has been done, check the surfaces of the discs and make sure here are no signs of any scoring or damage. Assuming all looks well take the car to an appropriate piece of quiet and straight, well sighted road and perform half a dozen medium pressure stops from 50 mph down to 20 mph to warm the brakes up. Avoid more than a minute between each stop so that the temperatures do not get a chance to deteriorate too much. Once the brakes are warm and the coast is clear, perform 2 or 3 hard stops from 70mph (where local laws allow!) to 20 mph, braking as hard as you can without locking up. Do not come to a halt between each stop, do them as fast as you can to get the brakes really hot."

I'm okay with that part. It doesn't sound unreasonable at all. Notice it says never come to a stop. All "stops" described are partial stops, like 70mph down to 20mph or whatever. I would still seek the manufacturer's recommended procedure for your particular pads. I can't find it with a short google search, so I would call your seller and ask him to call his Raybestos rep and ask for a written copy.

I'm NOT okay with the idea of getting them hot, stopping completely, and sitting there with the brake pedal held down. Never heard of that and it's something everybody at the track knows never to do.
 

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why you should not stop with hot brakes

When doing heavy braking, some of the material is worn off the pads and gathers on the disc. Left on the disc there can be some build up of material. This extra stuff causes a reduction in braking, vibration because the thickness varies, and even faster wear of the pad.

The AP brake option comes with specific bedding specifications. Part of the specification is to brake really hard and then do some medium braking to rid the disc of the excess material. Then another strong brake effort can be done to again bed the bonding agent and friction material in the pad, followed again by a medium brake to wipe the material off the disc.

After a track event, take special care not to even come to a stop with the brakes applied in the paddock. I look for a level spot or put a couple of rocks in place to hold my car and just roll it into position.

As far as I know, leaving a hot pad in contact with a disc is not a good idea.

Michael
 

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Discussion Starter #12
Yes, in the few track days I've done, I never applied the brakes after a session, finding a flat spot like you said and putting the car in gear instead.

The uberpost should be updated to get rid of that link! I haven't had any braking issues when I followed the advice on that link....no vibrating, etc. but I won't follow that advice again!

LMM
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Yes, in the few track days I've done, I never applied the brakes after a session, finding a flat spot like you said and putting the car in gear instead.

The uberpost should be updated to get rid of that link! I haven't had any braking issues when I followed the advice on that link....no vibrating, etc. but I won't follow that advice again!

LMM
:wallbang:
I understand the St-43 pads are good up to around 1400degF. If you didn't get any uneven deposit doing that then I suspect your break-in procedure wasn't agressive enough for them. If they were hot enough to bed in, such an act would have bad results.

xtn
 
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