Alcon Floating Disks - Binding?

[drhildr]

Just got the GT2 back from having the Alcon 360mm floating discs and new Pagid 29 pads fitted. Everything seemed fine but on the drive back it felt and sounded as if they were binding pad to rotor with a light scrubbing noise obvious as you drive.

Is this normal? I am loath to start the high speed bedding process if not!!

[Merritt]

Yes - that sounds normal...

Have you put RS29s on as well? If so, make sure you observe the correct pagid bedding in procedure

www.braketechnology.com/brakepadbedding.html

Steve

[drhildr]

Just spoke to JZM who don't think it should be happening - but are you saying that, in the real world, it does? If so does it go away as you bed in (I have fitted the 29's) as I don't want to chase a problem that does not exist!
Thanks Steve.

[Merritt]

Well - JZ fit a lot of them so they are the experts. I can only give my own experiences - and having fitted 2 sets of RS29s to new Brembo floaters I can confirm that they sound like they have a gentle 'rubbing' noise. This is worse if the anti squeal shims have been removed and not replaced. There should not be any strange marks on the discs and everything should be freely rotating if you jack the front of the car up.

If the brakes are getting hot due to the binding I would suggest something is not right... When you say you can feel the binding when you brake - can you explain what you mean?

[drhildr]

Hi Steve, everything went on fine. The chap I use is well used to changing brakes for me and I trust him 100%. On the ramp with the wheels jacked up everything span perfectly but on the way back to mine, and after the initial braking, they started this rubbing / scouring noise. The rotors were hot but not abnormally after some braking effort and the car will freewheel on the flat so they are not binding as such - just rubbing light(?)

Did you find that the noise went away after bedding in?

Thanks
David

[Merritt]

Hi David -

In the case of the Brembos, the rubbing noise is always there a little in the background but does get much better once everything is bedded in properly. The pads are the main cause which is why I mentioned the bedding in procedure. You really have to get them hot in order to get a transfer layer onto the disc. With that said, road driving will almost certainly remove the transfer layer until you get back on track again.

My discs / pads are always at their quietest for the first 100 miles after a track day.

To me it sounds like the noise you describe is normal. If there is no abnormal pulling when braking, I would bed the pads and discs in properly and see if they have got quieter.


Have fun

[drhildr]

Thanks - I will check the installation tomorrow just to be sure but you are not the only one with this view so it maybe a bedding in issue. Silverstone next Wednesday should tell me once and for all!!

[Merritt]

drhildr said:

Thanks - I will check the installation tomorrow just to be sure but you are not the only one with this view so it maybe a bedding in issue. Silverstone next Wednesday should tell me once and for all!!

Always worth double checking..

Silverstone will definitely be a work out for them, just be moderate with them for the first couple of laps.

Steve

[richad027]

This is normal with the Alcons an RS29 pads, you can often here a slight rubbing noise when you drive. This gets worse on the drive back after a track day but will will return to this slight rubbing sound once everything has really cooled down. My discs have done more than 15 track days now and are good for a few more yet on y third set of RS29s they can't be beaten for track performance.

Richard

[barrythompson]

How do you guys find the RS29's? i have just done approx 2k miles without washing the car and the wheels were black with the dust!!, a real pain in the a**e to clean and on the blue painted bit i cant get some of the dust off.

Any secret cleaners i could use??

Cheers,

Barry

[drhildr]

Thanks everyone - I am sure all will be fine after a double check and bedding in session. I had 29's on my old CSL and never found them too onerous to clean using most of the common wheel cleaners, the GT2 wheels are Permagarded and clean up with no effort at all.