40mm Ate problems

[Twickis]

Hi i´m a new owner of a 1979 BMW R100RS and now stuck with a problem

I have changed the seals on the caliper with a overhaul kit from Motobins but kept the old pistons, new ferodo pads and Brembo disc.
Tried to mount it to the bike but i can't get enough clearance to fit the caliper/pads over the disc!!

I have used a brake caliper tool to push the piston as far as i can.. I now wonder how far in should the piston be?
Mine are about 1,5mm above the rubber dust seal on both calipers.

[jagarra]

Is this on an ATE caliper, they should go in flush tot he seal. If this is an ATE unit check the back of your pads, the one that goes to the non piston side may have a couple of locating bumps that the piston side doesn't, could be the cause of your problem.

[Twickis]

No i tried that

[Mal S7]

How are the old pistons? They often develop some corrosion above the seal line. This may be preventing them going back all the way (or else damaging the seals)

[Twickis]

Not sure but i guess as old as the bike from 1979

I ordered a new set of piston, hope that will work it out.
Thanks!

[Twickis]

New pistons and now good as gold!