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      06-03-2009, 06:10 PM   #1
VictorH
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Track pad swap out

I have a few questions about track pads and their use:

1) If you use track pads for a DE event and then put the stock pads back in, do you have to bed in the track pads again (the old ones you used last time)?
2) If you get new rotors in the meantime between track events, would you need to re bed in the track pads? I guess the question is once a set of track pads has been bedded in are you then set for the life of the pad regardless of use or whether you changed rotors or not.
3) Is there any utility to checking your rotor temps with an IR temp gun after a session? If so what temps should you be seeing and if not, is the track pad performance only going to be a function of the temp range of the pad and the heat dispersing capability of your braking system.
4) How would you know if the brake fade you are experiencing is a function of poor or inadequate pad choice or the need for a bigger rotor and caliper set up?
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      06-04-2009, 02:17 AM   #2
ff1600
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Answers to your questions can be found on Stoptech's web site.

http://www.stoptech.com/tech_infotec...e_papers.shtml

Specific section on Pad and Rotor Bed-In here:
http://www.stoptech.com/tech_info/wp...contents.shtml

A brief summary:
1. Each time you switch pad compounds the bedding process must be repeated. The process removes the old pad material from the rotor and replaces it with material from the new compound. Which is why some prefer to change rotors as well when switching from track to street pads.

2. New rotors must have the pad material applied so yes, you must repeat the process even if the pads are used. Note: old pads on new rotors will result in very poor braking until the pads wear enough to match the rotor's new, smooth surface.

3. Brake temps are only useful if measured at peak operating temps. There are paints you can apply to the rotor to accomplish this.

4. Experience - either yours or what you can learn from others. Better brake cooling can help, as well.

There is a lot more detail in the Stoptech papers.
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      06-06-2009, 12:29 PM   #3
lucid
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Quote:
Originally Posted by VictorH View Post
3) Is there any utility to checking your rotor temps with an IR temp gun after a session? If so what temps should you be seeing and if not, is the track pad performance only going to be a function of the temp range of the pad and the heat dispersing capability of your braking system.
There is significant benefit to measuring your rotor temps right after a session. That doesn't allow you to pin down max operating temps, and as mentioned above that can be done with paint. However, knowing if you are at 300C vs 600C at the paddock is extremely valuable information.

For instance, if you are seeing 600C at the paddock and the pads you are using are rated at a MOT of 650C, you'd better be careful.

To fully understand how the pad behaves, you need to find information on the friction it provides at different temperatures (coefficient of friction vs. temp graphs). Some manufacturers provide that type of information. Of course, the friction the pad is capable of generating is irrelevant if your tires can't generate the required traction to cope with the torque.

Quote:
Originally Posted by VictorH View Post
4) How would you know if the brake fade you are experiencing is a function of poor or inadequate pad choice or the need for a bigger rotor and caliper set up?
In the context of pads and rotors, if you experience fade, these are the things you can do:

1. Don't try to control temperatures and use pads (and even rotors but that would be expensive) that are functional at higher temperatures.
2. Control/lower temperatures by increasing rotor cooling.
3. Control/lower temperatures by increasing rotor size.
4. All or a combination of the above.
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