[Dam]

Hi all,

I had the brake caliper rebuild from a local shop. I notice that the rear brake piston hasn't the typical cut off design. There is only a slight signs of the cut off. It is possible that after 50 years of usage the piston have worn out so much? I attache some photos. Thanks.

 

[ghnl]

I would not expect the piston to wear. Do you know if the shop re-used the old pistons or perhaps bought replacements?

 

[Alfajay]

What year and model Alfa are you working on?

If that is an ATE caliper from a 105 series car, then the piston and dust seal just look odd to me. The part of the piston that contacts the brake pad - and has that step - should be larger in diameter.

 

[genericwood]

Early ATE rear were much smaller piston diameter, no?

 

[Dam]

I would not expect the piston to wear. Do you know if the shop re-used the old pistons or perhaps bought replacements?

He said he reused the pistons. Not replacement. I also think that piston wear is really strange. Unfortunately I don't remember if the pistons were so worn before the rebuild.

 

[Dam]

What year and model Alfa are you working on?

If that is an ATE caliper from a 105 series car, then the piston and dust seal just look odd to me. The part of the piston that contacts the brake pad - and has that step - should be larger in diameter.

I'm working on a '72 GT 1300 Junior. The front pistons are 48mm, rear 38mm, if i don't remember bad. The front piston had an evident cut off design, the rear had no cut off. I attached you a photo of the front.

 

[Dam]

Early ATE rear were much smaller piston diameter, no?

Yep, i think that rear early piston are smaller, maybe something like 30mm, i don't remember well. I would have the late piston, 38mm. The problem is that the cut off or the step design of the piston is as if it had disappeared.