On my last trak day my brakes started to vibrate very hard, i have been going to trak days on my evo for many times and i have felt a litle vibration on braking but very litle and not hard and it goes away, but the last time it was really hard and it is there after some 200 or more miles of normal driving.

Stok brakes, rotors, lines and pads. super blue racing fluid, not the first pads but also not as new.

Any experience on these? did i bent a disc or what?

 

Warped rotors/missing shims/worn pads (does it screech?)

 

Sounds like warped rotors. How many miles on the stock rotors?

 

Checked to see if your rotors are grooved. Most likely it is your rotors.

 

only 15,000 miles, not worn pads they have at least 60% life left, but what do you mean by warped rotors or mising shims.

thanks

 

If the rotors are warped it means they're not perfectly flat on the braking surface that the pads touch.

This is probably a horrible metaphor, but its the best I could think of at the moment. Imagine a bent bicycle rim. If you spin that rim, the wheel goes back and forth as it spins. Now imagine something thats supposed to be in constant contact with that rim (your pads). Thats where your vibrating is coming from.

 

Assuming all your equipment passes visual inspection and your front wheels are horribly out of balance, Swankin is likely correct. Rebed the pads following RacingBrake's procedure, if that doesn't work, upgrade to some more purpose appropriate pads.

 

I had the same problem, particularly on barking in descents, the whole chassis would vibrate, particularly the steering wheel. I think it was due to "warped" rotors or more technically uneven pad deposits and perhaps cementite build up. Read this to get some background:

http://www.stoptech.com/tech_info/wp...rakedisk.shtml

Anyhow, I changed out my front discs to Powerslots and pads to Hawk HPS and the problem went away.

 

Jajajajaja :-)
That kind of stuff happen when 2 Evo IX are racing one against the other...

Saludos!!!

 

uneven pad deposits.

 

Can you just "rebed" a set of pads assuming you screwed the pooch the first time around? Essentially, can a proper bedding always overwrite an improper bedding? Or can the pad and rotor be permanently damaged by improper bedding?

 

I will take out the pads and take a god look at the discs, resurface the pads, and test driveit.

Order hawks for the trak and hope i dont have to resurface the discs

 

Did you use the e-brake at the track? It will cause pad transfer if the brakes are hot enough. Just leave the car in gear of get wheel chocks for when you are between sessions.

Or ignore this if you already do that =D

 

Please explain this further as I recall the e-brake being a drum-style mechanical brake.

 

Because the drum shoe material is not at all meant to tolerate heat, if you hit the track hard, heat up your brakes a lot, and then use the hand brake when you are parked after the session, you can have the shoes stick and/ or leave residue on the inside of the brake drum. Theoretically, this could have a similar feeling to warped rotors, but as you do not use the hand brake to actually brake, I find this unlikely...

Anyone, on my question above? Does a good bedding replace a poor one? Is it the cureall for brakes assuming they are not damaged?