Rattling of a Shimano Nexave roller brake In a suspended fork I use a Shimano Nexave BR-IM75-F roller brake and the cooling disc of the brake is not tighly fixed on the hub and it was like that since I got the roller-brake installed. I'm not sure whether this is "by design" or a fault. Opening the brrake side of the hub didn'r reveal nay way to make the fit tigher.

Anyway, It works fine for stoppping, but when I go over rough terrain the disc seems to rattles a lot, which creates quite a bit of noise. - Not nice!

Any idea what I can do?

Here is a picture of the Brake (I hope it helps understanding the situation!):
I have these fitted to my Carrera Subway 8.  

They seem to work well, but yes they rattle quite a bit when going over rough ground.  The cooling fin becomes tight when the brakes are applied so must be a direct connection to one of the friction faces.  

I might have a go a dabbing a bit of silicone at three points around the interface of the cooling fin to see if it subdues the rattling :-)