Rattle, Rattle, Rattle. Alcons?

[GregorFuk]

I'm loving my CSL but if I put the window down when running at low speed on a bumpy surface it sounds like a bag of spanners! Not Good.

However. I've noticed that just the lightest touch on the brake pedal will stop the rattling. This makes me think that the noise is coming for the Alcons I'm running on the front. Could it be the pads rattling in the calipers or the disks rattling on the bells? Or all of the above. Has anybody who's running Alcons suffered the same issue and resolved it? Or is it something I have to live with?

A quick peak through the front wheel tells me that I do have anti rattle springs fitted in the caliper. Well the offside one at least, I never checked the near side.

I notice from this month's EVO David Yu may be suffering from the same issue.

Any advice would be greatly appreciated.

Cheers

Gregor

[trackm3]

Don't you just love floating disks !!!!


QUOTE=GregorFuk;179864]I'm loving my CSL but if I put the window down when running at low speed on a bumpy surface it sounds like a bag of spanners! Not Good.

However. I've noticed that just the lightest touch on the brake pedal will stop the rattling. This makes me think that the noise is coming for the Alcons I'm running on the front. Could it be the pads rattling in the calipers or the disks rattling on the bells? Or all of the above. Has anybody who's running Alcons suffered the same issue and resolved it? Or is it something I have to live with?

A quick peak through the front wheel tells me that I do have anti rattle springs fitted in the caliper. Well the offside one at least, I never checked the near side.

I notice from this month's EVO David Yu may be suffering from the same issue.

Any advice would be greatly appreciated.

Cheers

Gregor[/quote]

[Rick H]

Mine don't do that.

They clank a bit here and there on light application - eg pulling on to the drive or in car parks but otherwise no real noise from them.

They are the Alcon Extreme discs which I think are semi floating rather than fully floating.

[GregorFuk]

Mine were bought second hand by the previous owner from a register member. I assume they came from shane@mbtech.

http://www.cslregister.com/forum/sho...ighlight=alcon

[shimmy]

You might be missing some pad retains clips like on the APs

[azrael]

If they are floating then you would hear them with the windows up (but yes bag of spanners). Possibly just clips as shim says if its quieter than that

[glendog74]

My APs do the same. I just drive faster/brake harder...

[shimmy]

Originally Posted by glendog74

My APs do the same. I just drive faster/brake harder...

fuck me.....youve changed. Have you grown a beard as well.

[rstoughy]

Gregor,
They were brand new and done 3 track days prior to the sale. All the clips were there when fitted but whether John put it in anywhere after they were fitted I couldn't say.
They were indeed from Shane as he was the one who fitted them onto the car under his ownership.
Its just a trait of the big brakes I'm afraid.
I would be interested in buying them back if you wanted to go back to standard???

[Mark CSL]

Easy fix if its got floating discs fit 4 nissan GTR disc springs sorted
they let the disc move when hot but hold them from ratteling

HOW IT WORKS

During braking, torque is transmitted from the disc to the bell through a fastener called a bobbin. This type of mounting system is designed to allow a specific amount of float in both radial and axial directions. This allows the disc to expand and contract under high temperature which reduces stress and increases longevity of the related components.

Brembo's unique anti-rattle disc hardware utilizes a spring fastener in order to slightly preload the assembly which eliminates the noise generally associated with floating discs.






The floating 2-piece anti-rattle disc hardware system, commonly used in high performance braking systems, was actually developed by Brembo back in the mid 90's.

This innovation was initially engineered exclusively for the McLaren F1 supercar which is why the hardware is often nicknamed the "McLaren" spring.

you only need 4 for each disc the silver part in this picture and the square part on the d-type bobben or a small washer will do