AberdeenBikers

CBR600F with solid discs and many other similar bikes have little plastic washers between the disc and the wheel where the bolt passes through. I have come across plenty of wheels where these washers have been omitted.
Does anybody know the function of the isolators - my hunch is either heat or keeping the alloy and steel disc apart for dissimilar metal corrosion protection?

not2fast wrote:CBR600F with solid discs and many other similar bikes have little plastic washers between the disc and the wheel where the bolt passes through. I have come across plenty of wheels where these washers have been omitted.
Does anybody know the function of the isolators - my hunch is either heat or keeping the alloy and steel disc apart for dissimilar metal corrosion protection?

At a guess I would suggest it reduces vibration and brake noise...

It's to isolate the disc from the hub/ disc carrier.
the disks get ferkin hot in use and expand / contract willy nilly,
Without the isolation the disks used to crack.

the other reason is to allow the disk to float laterally to keep it centered in the caliper thus not bending the disk in use.

i think . . . .?

airwave wrote:It's to isolate the disc from the hub/ disc carrier.
the disks get ferkin hot in use and expand / contract willy nilly,
Without the isolation the disks used to crack.

the other reason is to allow the disk to float laterally to keep it centered in the caliper thus not bending the disk in use.

i think . . . .?

I don't think it is the "buttons" he's referring to ?

Correct A1 - These are fitted to fixed discs used on early CBR600's. They are thin flexible plastic washers that are bolted up tight between the disc and the wheel. In the Haynes manual they are referred to as shims and in the H0NDA parts microfiche they are called 'shims, damping'.
They are not fitted to the rear disc which mounts otherwise identically.

Item 12 in the picture. Any ideas?

they are to stop the two diffrent metals binding with heat and to isolate braking vibrations

They sound like damping shims to me.

Shims, for damping I'd guess.