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Please does anyone know whether the dust seals on the 500 rear caliper should be 'attached' to the caliper? The original dust seals I removed have a lip in the rubber, which sits in the caliper groove, fixing them in place and thus allowing the piston to move independently of the seal. The new ones I have received from Mdina (shown in photo) are fractionally smaller in outer diameter and do not have any lip, thus I believe they will simply move with the piston. I could always fix them in place with a little silicone, but would appreciate any comments. Many thanks!

Actually I´m trying to reanimate a 500 (project name "Frankenstein" because of the actual state, an had to buy new pistons for the rear brake. The new pistons have a diferent design so I had to order new rubber seals as well, because the old ones (still in good condition) didn´t fit well.

(have been out of contact for a mounth or two because of problems with login and ... )
norbert

The dust seal does need some form of positive location to both piston and calliper. It is a bit of a bodge, but if you are determined to use them and want to use silicone, then it would pay to use high temp sealant. Are the old seals ok or repairable?

That´s what I wanted to say:
The design of the new pistons I bought is diferent to the old ones. Therfore you need dustseals for this new type of piston if you want to fit them.
In my front calipers I never used any dustseals. It´s my first Morini with rear disc brake and to me the caliper seams to be more exposed to dirt and dust than the front brakes. So I ordered the new seals after noting that the old ones don´t fit.
Looking at the foto from Jonny this piston seams to be brand new. So the question is: Is this a dust seal for the new type of piston or of the former/old piston? If it does not fit properly I guess it is a new Type piston with an old type seal. That will not work and may become dangerous. Then I woud prefer without seal.

I didn´t make pictures from the diferent pistons. The only one I have is this one with the old pistons mounted

Thanks for your replies. I have taken a gamble and ordered this one from eBay in the USA (I can't seem to find the same item here in the UK). From the photo, the dust seal looks very similar if not identical to the original one I have just removed. Time will tell.