Possible brake pad/disk problem

[psycho]

I recently installed some Ferrodo DS2500 pads and some Brembo Max HC Groved disks. After the last track day (kindof a bedding in session I guess) I started getting some vibration in the brake pedal under light braking. No I didnt park with the handbrake on

It only happens on light braking between about 50-110kph and dosnt really exist at lower or higher speeds. It is most prominent right at 80kph with an audible speed equivelant (slows down as the car slows) vibration.

I took it to Renault and got the head service guy to take it for a drive and he says that its probably not a warped disk but rather thinks its just what is gonna happen with hard race pads and disks. It might also be possible that its just the groves in the disks that are causing it.

So, what do you guys reakon? Anything wrong? The brakes do still work fine....very fine but I wanna be sure nothing is gonna give out on me.

 

[16v_jon]

it'll be some kind of resonence at a certain speed from the disks

 

[psycho]

it'll be some kind of resonence at a certain speed from the disks

Does that mean warping or is it something else?

 

[psycho]

Anyone else? What should I be looking for that matches these symptoms?

 

[Fred@BTM]

did you remove the pad shims when you installed the DS2500's??? (small stainless steel plate at either end of the pad carrier)

 

[psycho]

did you remove the pad shims when you installed the DS2500's??? (small stainless steel plate at either end of the pad carrier)

I didnt install them so im not sure. I will find that out asap but should they be in or out?

 

[psycho]

Well, my pads or disk are still vibating under brakes. It didnt go away

Now about these shims you're talking about Fred, are they the black metal piece that come stuck to the back of the pad material? Do they need to be pryed off?

 

[16v_jon]

Well, my pads or disk are still vibating under brakes. It didnt go away

Now about these shims you're talking about Fred, are they the black metal piece that come stuck to the back of the pad material? Do they need to be pryed off?

Its a very thin piece of metal attached to the underside of the caliper

 

[psycho]

Well, my pads or disk are still vibating under brakes. It didnt go away

Now about these shims you're talking about Fred, are they the black metal piece that come stuck to the back of the pad material? Do they need to be pryed off?

Its a very thin piece of metal attached to the underside of the caliper

And for these pads they need to be removed?

 

[MRBILLYUK]

These are what Freds referring to .

 

[psycho]

Oh cool, thanks for that! Next step is to check to see if they are fitted.

 

[psycho]

Ok, finaly got around to checking my shims and found there are none installed. Is this something I should get put back on or are they supposed to be removed?

 

[TomTom]

If you don't bed in new/pads and discs properly the first time they get hot you can warp the discs... Doesn't usually happen but it can.

Did you clean all the corrosion/rust off the mating face on the hub where the disc sits onto, needs to be as clean as you can get it really.

 

[psycho]

If you don't bed in new/pads and discs properly the first time they get hot you can warp the discs... Doesn't usually happen but it can.

Did you clean all the corrosion/rust off the mating face on the hub where the disc sits onto, needs to be as clean as you can get it really.

It wouldnt be corrosion because the vibration only started happening after a few laps on a track day. And I didnt use the handbrake at the track so I cant see how they would have warped.

Surely Brembo Max HC's wont warp unless under extreem heat for a long period?

 

[TomTom]

The handbrake works the rear pads mate not the fronts.

 

[MRBILLYUK]

Try taking the discs off and turning them 180 degrees , they might be running out a bit causing the vibration .